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HomeMy WebLinkAboutSDP 99-16; KINDERCARE CARRILLO; GEOTECHNICAL ENGINEERING EXPLORATION; 1999-07-16. r~ ·1··~f}' ' -.-,.,,. :!-;; I\~:: , ... , ~~ I;:\ f ·( < Geotechnical Engineering Exploration and Analysis Proposed KinderCare Learning Center Melrose Drive and Carrillo Way· Carlsbad, California Prepared For: KinderCare Learning Centers, Inc. Portland, Oregon. July 16, 1999 Project No. 2G-9907002 · GILES E:NGINEERING Assoc1ATES, 1Nc. I I I I I I I I I I I I I I. I I I I .~ GILES E:NGINEERING Assoc1ATES, 1Nc. -- •Atlanta, GA GEOTECHNICAL, ENVIRONMENTAL & CONSTRUCTION MATERIALS CONSULTANTS • Dallas, TX • Los Angeles, CA • Madison, WI • Milwaukee, WI · • Seattle, WA • Washington, D:C. KinderCare Leaming Centers, Inc. 650 NE Holladay Street, Suite 1400 Portland, Oregon 97232 Attention: Mr. Philip DePasquale III Senior Engineering Coordinator July 16, 1999 Subject: Geotechnical Engineering. Exploration and Analysis Proposed KinderCare Leaming Center Melrose Drive and Carrillo Way Carlsbad, California Project No. 2G-9907.002 Dear Mt. DePasquale: In accordance with your request and authorization, a Geoteclmical Ellgineering Exploration a11d Analysis has been conducted for the above referenced project. Conclusions and recommendations developed from the exploration and analysis are discussed in the accompanying report. We appreciate the opportunity to be of service on this project. If we may be of additional assistance, should geotechnical related problems occur or to provide monitoring and testing services during construction, please do not hesitate to call at any time. Very truly yours, Enclosure: . Report >,fo. 2G-9907002 Distribution: (5) Addressee JEH,c 1-geo.G9907002 4875 East LaPalma Avenu? • Suit? 607 • Anaheim, CA 92807 -· ·--------_ _. ,. __ ,,.. ,,..,,..,,..,... -... _., , _____ ,_.,....._•1,.. ____ ~--- I I I I I I. I I I I I I I I I I I I I GEOTECHNICAL ENGINEERING EXPLORATION AND ANALYSIS PROPOSED KINDERCARE LEARNING CENTER MELROSE DRIVE AND CARRILLO WAY CARLSBAD, CALIFORNIA PROJECT NO. 2G-9907002 1.0 EXECUTIVE SUMMARY OUTLINE The following is a brief summary outline of the report conclusions and recommendations. The accompanying report should be read in complete context for proper interpretation. Site Development • the site is believed to have been graded in conjunction with mass grading act1v1t1es conducted in the vicinity of the site. A retention basin currently exists on the site and has resulted in a 6-foot elevation differential in the proposed building area. Copies of previous grading and engineering reports are recommended to be provided for our review. • Recommendations for site development ate based upon an assumed floor elevation (as discussed in the report) which requires the placement of about 2 to 8 feet of fill to raise site grades. • Building Area: Preparation of the proposed building. area will be dependent upon the selected foundation alternative. The use of a moderately rigid shallow foundation system requires the material placement of a select low expansive (EI less than 30) structural fill material. The structural fill should not be free-draining granular soil. The use of a more rigid waffle slab or Post-Tensioned slab does not require the use of a select material to raise site grades. • Dry Weather: Extensive overexcavation or undercutting is not expected to be necessary, but aeration and processing of the subgrade may be necessary in localized areas to facilitate proper recompaction. • Wet Weather: Undercutting or pverexcavation an additional 10 to 18 inches to develop a stable sub grade if subgrade stability problems develop. • Additional geotechnical evaluation is recommended for the design and construction of retaining wails and/or slope grading to accommodate grade differentials. ~ GILES ENGINEERING ASSOCIATES, INC I I I I I I I 1· I I I I I I I Proposed KinderCare Learning Center Carlsbad, California Project No. 2G-9907002 Page2 Building Foundation Alternatives • Rigid Waffle Slab or Post-Tensioned Slab supported on properly prepared existing expansive soils. • Moderat~ly rigid spread footings supported on very low expansive structural fill used to replace existing expansive soils. • Suitable bearing soil anticipated to exist at depths of 1 to 2 feet below existing grade or at nominal embedment depth within structural fill to raise site grades. Building Floor Slab (Moderately Rigid Foundation Alternative) • Moderately rigid slab-on-grade or turned-down slab, 5-inch minimum thickness, supported on a properly prepared sub grade consisting of low expansive fill. • Minimum slab reinforcing recommended to consist of No. 4 bars at 18-inch on-center spacings with slab structurally connected to perimeter footings. Pavement • Asphaltic Concrete: 3 inches in thickness • Crushed A~gtegate Base Course:. 10 inches in drive lanes, 7 inches in parking stall areas. • Portland Cement Concrete: 7 inches in thickness underlain by 4 inches of base course in high stress areas such as the trash enclosure loading zone. • Increased pavement maintenance should be expected· due to the expansive soils and existing fill. Environmental Considerations • No volatile odors, stafoings, or volatile vapors vapor detected utilizing a photoionization detector (PID). I ~ GILES ENGINEERING ASSOCIATES. INC I I I I I I I I I I I ·1 I ·I I I I I I Proposed KinderCare Leaming Center Carlsbad, California Project No. 2G-9907002 ,Page 3 2.0· SCOPE OF SERVICES The scope of services authorized for this project included a site reconnaissance, subsurface exploration, field and laboratory testing, and a geotechnical engineering analysis to provide criteria for preparing the design of the building foundations, building floor slab, and parking lot pavement along with site preparation recommendations and construction/design considerations for the proposed development. The grade differential between the general site grades and, the adjacent roadways may require graded slopes or retaining walls. Recommendations for slope grading and/or retaining wall construction was not included in the authorized scope of services, but can be provided upon request. In addition to the previously described geotechrtical services, all below-grade soil samples recovered from the field exploration program were subjected to a Limited Volatile Organic Compound Vapor Scan using a Photoionization Detector. Further evaluation of the environmental aspects was beyond the authorized s<;;ope of services, but can be provided upon request. 3.0 SITE AND PROJECT DESCRIPTION 3.1 Site Description The site i& located at the southwestern comer of the intersection of Melrose Drive and Carrillo Way in Carlsbad, California. At the tii;ne of field exploration, the proposed site consisted of a vacant lot with a moderate growth of short grass and weed vegetation. The northem region of the site which included the northern two-thirds of the building area included a retention basin with a corrugated metal standpipe. The site is located within what appears to be a mass graded area with vacant lots to the north, east and south and new residential housing to the west. Significant variance in site grades exists in the vicinity of the site. The general grade to the north of the site was estimated to be about 20 feet lower than the average grade of the site. The grades of the properties to the east and south were estimated to be 15 to 30 feet higher. The property to the west was about 5 feet higher in elevation. The grade differential is achieved by descending slopes which border the site to the east and south. The slopes appear to have been constructed during previous grading and were observed to be vegetated with grass and young trees. r..£:~-~-,------~ GILES ENGINEERING ASSOCIATES, INC. I. I I I I I I I I I I I I I I I I I I Proposed KinderCare Leaming Center Carlsbad, California Proje.ct No. ZG-9907002 Page 4 3.2 Proposed Project A description of the pr9posed development is presented. in Appendix A which includes the anticipated structural loads and parking lot traffic intensity. A specific floor elevation of the proposed structure was not provided in the preliminary project information. Based upon the encountered site topography, a finished floor at El. 75, referenced to the benchmark on Figure 1, included in .Appendix B has been assumed for geotechnical analysis. Existing site grades at the test boring locations in the proposed building range from about El. 66 within the· retention basin to El. 72 within the eastern region of the pad. Site grading is, therefore, expected to include the placement of 2 to 8 feet of structural fill to establish the necessary site grades to accommodate the assumed floor elevation, exclµsive of site preparation or overexcavation requirements. 4.0 SUBSURFACE EXPLORATION 4.1 Subsurface Exploration Field exploration consisted of seven test borings extended to depths of 5 to 25 feet below existing grade. Three of the test borings were extended to depths greater than typically proposed to allow sufficient exploration below the existing fill. The approximate test boring locations are indicated on the Boring Location Plan (Figure 1 ). The Boring Location Plan, as well as copies of the Test Boring Logs (Records of Subsurface Exploration) are enclosed in Appendix B. Field and laboratory test procedures are enclosed in Appendix C and D, respectively. The terms and symbols used on_ the Test Boring Logs are defined on the General Notes in Appendix E. 4.2 Subsurface Conditions The subsurface conditions as subsequently described have been simplified somewhat for ease of report interpretation. A more detailed description of the subsurface conditions at the test boring locations are described on the test boring logs enclosed in Appendix B of this report. The conditions encountered at the test ·boring locations indicate the proposed site is underlain by existing fill to deptb.s of 5 to 14 feet below existing grade. Soils classified as possible fill were encountered at several boring locations below existing fill to depths of 12 to 18 feet. The existing and possible fill generally consisted of very stiff consistency diatomaceous clayey silts and silty clays. The native soils generally consisted of firm relative density silty or clayey sands or very stiff consistency silty clays and clayey silts to at least the maximum depths explored. Material classified as weathered sandstone bedrock was encountered at a depth of about 18 feet at Test Boring Nos. 4 and 5. ~ GILES ENGINEERING ASSOCIATES, INC I I I I I I I I I I I I I I I I I I I Proposed KinderCare Leaming Center Carlsbad, California Project No. 2G-9907002 Pa,ge 5 Expansion Potential Soil mechanics laboratory testing included Expansion Index (EI) testing in accordance Witb UBC Standard No. 18-2 on a representative sample of the soils encotmtered to a depth of 5 feet at the location of Test Boring No. 1. The results of this testing indicate the soils possess a high expansiye potential (EI=l05). Atterberg Limits determination on this sample indicates the soils possess very high plasticity (LL=54, PI=35). Atterberg Limits determination was also performed on samples selected for consolidation testing. Laboratory re.suits indicated that the samples had Liquid Limits (LL) ranging from 46 to 54 and Plasticity Indices ranging from 23 to 31 indicating that the these soils possess a high degree of plasticity. Soil Consolidation Specialized consolidation testing was performed on two of the relatively undisturbed soil samples, each collected from a depth of 3 to 4 feet from Test Boring Nos. 1 and 3. The results of testing are shown in Figures 2 and 3 in Appendix B. The test results in4icate the sample tested from Test Boring No. 1 is somewhat compressible and susceptible to a low magnitude of collapse upon water infiltration. The sample tested from Test Boring No. 3 exhibited relatively less compressibility and a potential for expansion. The test sample swelled about 1 percent under a normal pressure of 1,600 psf upon water infiltration. Corrosivity Representative, composite samples of the near surface soils have been submitted to an analytical testing laboratory to determine the corrosivity of the soils to Portland cement and buried ferrous metals. Upon completion of this testing, an addendum to this report will be issued which presents the results of testing and appropriate recommendations for concrete mix design and buried utility installations. Groundwater Free water was not encountered during drilling operations. Observations conducted upon completion of drilling and removal of drilling augers indicated no groundwater accumulation within the test borings above the depths at which the test boreholes caved. However, due to lower permeability cohesive clay soils present throughout various depths within the test borings, a more accurate depiction of the groundwater conditions would require leaving the boreholes open for a ·considerable period of time or the installation of temporary groundwater monitoring wells. Based on field observations and the relative moisture contents of the recovered soil samples, the groundwater table is considered to have existed below the maximum exploration depths (25 feet). ~ G!LES ENG!NEERING ASSOCIATES, !NC I I I I I I I I I I I I I I I I I Proposed KinderCare Leaming Center Carlsbad, California Project No. 2G-9907002 Page 6 5.0 CONCLUSIONS AND RECOMMENDATIONS Conditions i:rnposed by the proposed development have been evaluated on the basis of the assumed floor elevation and engineering characteristics of the subsurface materials encountered in the borings and their anticipated behavior both during and after construction. Conclusions and recomrhenda~ions presented for the design of building foundations, building floor slab, and parking lot pavement, along with site preparation recommendations and construction considerations are discussed in the following sections of this report. General · comments and other limitations relative to this report are presented in Appendix E. Development of the proposed site entails soil and foundation-oriented considerations, especially with respect to the expansive potential of the soils and the presence of existing fill. Grading difficulties should be expected during wet weather. The selection of final grades may necessitate graded slopes or the use of retaining walls to achieve grade differentials. Recommendations presented in this report are predicated upon site preparation, foundation, floor slab, and pavement construction monitored by a qualified geotechnical engineer. Recommendations for slope grading or retaining wall construction can be provided upon request. 5.1 Soil Vapor Scan . The recovered soil samples did not exhibit odors or discolorations which would be potentially indicative of volatile organic compound (VOC) content. In addition, the results of the VOC vapor scan conducted on each of the recovered soil samples using a Photoionization Detector (PID) did not indicate the presence of any detectable levels of volatile orgaruc compounds. s.z Seismic Desii:n Considerations The proposed site is located in a seismically active region of California. The site is not, however, located within a currently designed Alquist-Priolo Earthquake Fault Zone. Determination of the appropriate seismic design paraqieters utilized for structural purposes was not included Within the scope of authorized services and is typically not performed by the geotechnical engineer. Seismic design parameters should, therefore, be determined by the structural engineer. The potential for liquefaction to occur at the proposed site is considered to be very low due to the predominantly cohesive characteristics of the soil profile encountered during drilling and the anticipation that the site is underlain by formational material. Liquefaction is, therefore, not a consideration in site development. ~ . GILES ENGINEERING ASSOCiAfES, INC I. I I I I I I I I I I I I I I I I I I Proposed KinderCaFe Learning Center Carlsbad, California Project No. 2G-9907002 Page 7 5.3 Geotechnical Desi~n Considerations. The soils underlying the proposed site possess very high plasticities and a corresponding high expansion potential, especially if the soils dry in the interim prior to construction. In addition, the existing fill exhibited variances in support/compressibility characteristics as indicated by ~he consolidation test results. Special considerations arise for site development and building foundation and floor slab design. In consideration of the expansive potential and support characteristics of the soils, two alternatives for development are considered to be feasible: • Placement of very low to non-expansive, non-free draining granular structural fill to a depth of at least 5 feet below pad grade to allow the use of moderately rigid shallow spread footing foundation and slab-on-grade. • Nominal building subgrade preparation ( e.g. scarification, moisture conditioning, and recompaction of existing soils) followed by placement of fill to established finished grade with the use of either a rigid slab-on-grade foundation such as a waffle slab or post-tensioned slab if the structural fill consists of similar potentially expansive soils. In consideration of the grade differential whi9h currently exists across the proposed building area, a feasible approach to building pad preparation to reduce foundation rigidity requirements and associated costs is to establish a minimum 5-foot thick layer of select, non-free draining, low expansion potential, structural fill. Based on the assumed finished floor (El. 75.0), some overexcavation on the order of 2 to 3 feet will be required in the eastern region of the building area to allow placement of the recommended thickness of select fill. The excavated soils are expected to be reused in the low area of the site and still be able to place the minimum required thickness of select fill. The excavated soils may also be reused as fill in the proposed parkiIJ.g area. The selection of the finished floor and the associated site grades could have a significant impact upon geotechnical recommendations as presented in this report. We therefore recommend a copy of the project grading plan be provided for our review relative to the recommendations presented in this report. In consideration of the grade differential between the adjacent roadways and the general site grade, we anticipate retaining walls and/or slope grading will be required for the subject property. Retaining wall recommendations, slope regrading recommendations, or slope stability evaluation were not included within the authorized scope of services. Such services can be provided following completion of the final grading plan. (~__,....,....,..------,---~ GILES ENGINEERING ASSOCIATES, INC. I. I I I· I I I I I I I I I I I I I I Proposed KinderCare Learning Center Carlsbad, California Project No. 2G-9907002 Page 8 5.4 Site Development Recommendations The recommendations subsequently presented for site development are based upon the conditions encountered at the test boring locations and the time of year in which exploration was performed. Bids for site development should be based on time of year in which construction is planned. Where applicable, the following rec<;>mmendatiorts are presented for the previously described site development options. Site Clearing Preparation of the proposed site should include proper abandonment of the standpipe associated with the retention · basin. Preparation should also include removal of debris or deleterious materials that may exist as well as any vegetation and soils with significant organic content. On the basis of the conditions encountered at the test boring locations and the appearance of the site at the time of exploration, surficial stripping on the order of 2 to 4 inches is expected to be necessary to remove surface vegetation. Localized undercutting or overexcavation may be required within filled depressions or swales not evident from site appearance and may be needed to remove unstable soils in the former retention basin. The actual depth of site stripping should be determined by a qualified geotechnical engineer based on the organic content and stability of the material. Dry Weather Grading In the event that site preparation artd grading activities are conducted during dry, fair weather conditions, no special ov.erexcavation or undercutting is expected to be necessary provided the subgrade is initially in a stable condition. Overexcavation may be necessary in the eastern region of the proposed building area to allow placement of a minimum 5-foot thick select structural fill and the use of a moderately rigid shallow foundation system and slab-on-grade floor. Wet Weather Construction Subgrade stabi'lity problems should be expected if si'te development and grading activities are conducted during wet weather. In the event subgrade stability problems are encountered, undercutting on the order of l O to 18 inches should be expected to be necessary to achieve a stable subgrade. The estimated depth of dverexcavation is based upon the moisture sensitivity of the soils and the anticipated effect of wet weather grading. Alternatively, subgrade stability may be achieved by chemical modification of the soils through the addition of hydrated lime or Portland Cemem followed by proper compaction or through placement of a coarse aggregate working mat. If overexcavation or specialized sub grade stabilization techniques are required, the ~ GILES ENGINEERING ASSOCIATES, INC. I ' I I; I: I I I I I I I I I I I I I I Proposed KinderCare Learning Center Carlsbad,. California Project No. 20-9907002 Page 9 actual depth of overexcavation or stabilization method should be determined by a qualified geotechnical engineer based on field evaluation and testing. Building Area The preparation of the building area will -be dependent upon the selected development alternative. With the use of a rigid foundation or Post-Tensioned slab, no specific overexcavation will be necessary. The building pad may, therefore, be prepared as described in the "Proofroll and Compact Subgrade" section of this report. However, if a moderately rigid shallow foundation and floor slab is desired, preparation of the building pad is recommended to include ~mfficient overexcavation of the existing soils to allow placement of a minimum 5-foot thick select structural fill mat below proposed pad grade and to a minimum lateral extent of 5 feet beyond the building footprint. Upon completion of overexcavation, the bearing suitability of the subgrade in the areas of footing influence should be evaluated using the criteria established in the "Foundation Recommendations" section of this report. Prior to fill placement to raise grade, the subgrade should be prepared as described in the "Proofroll and Compact Subgrade" section of this report. Proofroll and Compact Subgrades Up<:m completion of site clearing, subgrades within the proposed building and new pavement.areas as well as areas to serve as the subgrade for placement of structural fill should be proo:frolled, in the presence of the geotechnical engineer, with appropriate rubber-tire mounted heavy construction equipment or a loaded dump truck to detect soft, yielding soils which must be removed to a stable subgrade. Proofrolling should be performed prior to fill placement in low areas, but after cutting in high areas of the site. ~ollowing proofrolling and completion of any necessary overexcavation, the subgrades should be scarified to a depth of 6 to 8 inches, moisture conditioned to about 2 to 4 percent above optimum moisture content and recompacted to at least 90 percent of the Modified Proctor (ASTM D1557-91) maximum density. The scarification and moisture conditioning of the soils above optimum is considered critical on the site due to the expansive potential of the soils. Low areas and excavations may then be backfilled in lifts with the appropriate structural compacted fill. The selection, placement and compaction of structural fill should be performed in accordance with the project specifications or as modified by the recommendations in this report. The Guide Specifications included in Appendix E (Modified Proctor) of this report are recommended to be used as an aid in developing the project specifications. Recompaction of the subgrade .immediately before pavement and floor slab construction may be needed due to weather and construction equipment traffic effects on previously compacted soil. ~ GILES ENGINEERING ASSOCIATES, INC. . \ I I I. I I I I I I I I I I I I I I I :• Proposed KinderCare Leaming Center Carlsbad, California Project No. 20-9907002 Page 10 Reuse of On-site Soils Reuse of the on~site soils as structural fill is considered feasible with the use of a rigid shallow foundation alternative and as structural fill below the select structural fill, but careful control of the moisture content is recommended due to the moisture sensitivity and expansive potential oftlle soils. Soils of this nature are highly sensitive to moisture and must be compacted within a narrow range of optimum to achieve proper compaction for load bearing and pavement support and reduce expansion potential. Recompaction is recommended to be ·performed at a moisture content of 2 to 4 percent above optimum. Difficulty in achieving proper compaction should be expected due to the diatomaceous nature of the soils. Consequently, consideration should be given to importing structural fill for backfilling utility trenches to reduce recompaction difficulties. The on-site expansive soils are not recommended for use as the select structural fill (i.e., the fill within the upper 5 feet of finished pad grade) within the building area with the use of a moderately rigid shallow foundation and floor slab alternative. Imported Structural Fill Material imported to the site for use as structural fill within the building area for the moderately rigid foundation alternative is generally reconutlended to consist of low expansive (EI less than 30) and non-free draining granular soils (at least 25 percent passing No. 200 sieve). With the use of a rigid slab or Post-Tensioned slab foundation, on-site soil may be reused as. structural fill in the building area, but the soil should be recompacted at a moisture at least 2 to 4 percent above optimum moisture as previously discussed. Moisture Sensitive Subgrade Soils Soils which will be exposed by the subgrade preparation are highly moisture and disturbance sensitive. The subgrade soils will become unstable if allowed to increase in moisture content or ate disturbed (rutted) by construction traffic. The site should be graded to prevent water from ponding within construction areas and/or flowing into excavations. Accumulated water must be removed immediately along with any unstable soil. Foundation concrete should be placed and excavations backfilled as soon as possible to protect the bearing grade. The need for specialized subgrade stabilization will be dependent upon the condition of the subgrade at the time of development and precautions taken during construction to protect the subgrade. In addition, the soils are capable of moderate volume changes with fluctuation in moisture.. The soils are recommended to be maintained at in-situ moisture contents of at least 2 to 4 percent a.hove optimum moisture to a depth of at least 6 to 8 inches. If the subgrade becomes dry or desiccated below the recommended .range above optimum moisture, the soils should be either overexcavated, moisture conditioned to the recommended range above optimum and recompacted or replaced with suitable structural compacted tilt ~ GILES ENGINEERING ASSOCIATES, INC I I I I I I I I I I I I I I I I I I I Proposed KinderCare Leaming Center Carlsbad, California Project No. 2G-9907002 Page 11 Utilitv Trench Backfill Due to the expansive nature of the on-site soils, it is recommended that all utility trenches within the building area be backfilled with the recommended Imported Structural Fill if a moderately rigid shallow foundation and floor slab are used. The use of an open graded granular material is not recommended, since this could function as a conduit, allowing water to flow beneath the structure. The potential for subsurface water flow to occur is also enhanced by the grade differential which could provide a pressure head for water to flow beneath the site. If the use of a granular backfill material within ~he trenches is required, it is recommended that all trenches be provided with a clay collar at the point where the trench crosses the building line. If a well graded granular material (at least 25 percent passing the No. 200 sieve) is used, the use of a clay collar is not considered necessary. 5.5 Site Development Considerations Construction Dewatering The groundwater -table was considered to have existed at depths in excess of 25 feet below existing grade at the time of field exploration and is anticipated to exist at a similar depth on a long term basis. Groundwater is not expected to be encountered during construction. However,. perched water could develop seasonally at shallower depths. Dewatering by the use of conventional sump pumps placed within pits within the excavations is expected to be necessary if localized perched water conditions are encountered. Soil Excavation Significant excavation stability ( caving) problems are not anticipated for shallow excavations under short term exposure conditions due to the generally cohesive nature and hard consistency of the soils. Deeper excavations with steep excavation sidewalls may require some form of lateral support such as shoring or bracing. All excavations should be performed in accordance with Cal-OSHA regulations. The stability of any cuts into the adjacent ascending slopes should be evaluated by the geotechnical engineer and the engineering geologist. Although excavations below depths of 15 feet are not expected for the proposed development, decreased excavation rates should be anticipated due to the presence of hard consistency formational material. Test pits performed by the contractors during the bid phase of the project should be considered to better evaluate the excavation characteristics of the formational material if deep utility excavations are required. ~-G-'--IL_E_S-,.E-N--:-G-IN-EE_RI ___ N_G_A_S_S_O_C_IA_T,...,E_S_, IN-C-. ------------ I I I I I I I I I I I I I I I I I I I Proposed K.ihderCare Leaming Center Carlsbad, California Project No. 2G-9907002 Page 12 Landscape Planters Final grading, plumbing design and positioning of landscaped areas is very important to ensure that surface and sprinkler water and downspout drainage does not collect arou_nd the building and thereby allow expansive soils to increase in moisture content which could activate the expansive soils resulting in soil heave and possible structural damage. Any plumbing leaks that develop must be corrected irtlmediately. If possible, sprinklers should not be placed ip the immediate vicinity of the structure, or a polyvinyl sheet (10 mil minimum) should be provided below planting areas to help prevent moisture changes within the expansive soils. If a polyvinyl sheet is used, it is recommended that it extends from exterior grade along the stem wall to a depth of 12 inches below the bottom of the landscape planter and extend away from the building a minimum distance of 5 feet at a sufficient grade to promote drainage away from the building. Large shrubs and trees should not be planted in the immediate vicinity of the structure since root systems can cause significant local variations in soil moisture content, which could result in subsequent movement (settlement/heave). Excessive runoff water from pavement cleaning operations may also affect the soils beneath the building and pavement, and should be carefully controlled. 5.6 Rit:id Foundatfon Recommendations The soils which underlie the proposed site possess moderate to high plasticity characteristics and possess a high expansion potential. _ As previously discussed, several alternatives exist for development depending upon the desired foundation system. The following recommendations are provided for use in design of the foundation systems which are expected to be most feasible for the proposed development without special preparation of the building area and the use of similar, potentially expansive soils to raise site grades. Post-Tensioned Slab-on-Grade The proposed building structure may be supported by a rigid Post-Tensioned (P-T) Slab- on-Grade which will allow the use of the high expansive soils for direct building support at grade. Parameters provided herein for use of a post-t~nsioned slab foundation system are based upon the Uniform Building Code C(JBC) Volume 2, Division III, Section 1816, Design of Post- Tensioned Slabs-On-Ground, 1994 Edition. The P-T slab referenced in this report is considered to be a monolithically constructed floor slab and grade beam system. The load imposed by the bearing walls and columns will be supported uniformly by stiffeners and grade-beams, with relatively little load supported by the slab. The post-tensioned slab for support of the proposed structure may be designed for a maximum, net allowable soil bearing capacity of 2,000 pounds per square foot (psf) founded at r..£::----,..------'------:-----~ GILES ENGINEERING ASSOCIATES, INC. I_ I I I I I I I I I I I I I I I I I I Proposed KinderCare Leaming Center Carlsbad, California Project No. 2G-9907002 Page 13 least 1 foot into suitable bearing existing soils or a properly compacted structural fill. The maximum amount of dead load from the building structure should be utilized to help resist uplift attributed to the expansive nature of the soils. The structural design of the post-tensioned slab should be based on the following parameters: Thomthwaite Moisture Index (TMI): Percent Clay of Percent Passing No. 200: Edge Moisture Variation Distance ( eJ Differential Moveme~t (y J: Rigid Waffle Slab -20 50% Center Lift: Edge Lift: Center Lift: Edge Lift: 5 feet 25 feet 2.62 inches 0.75 inches . As an alternate to a p.., T Slab, the structure may be supported by a rigid slab-on-grade foundation (Waffle Slab) with thickened sections to support bearing walls and columns. The rigid slab alternate is recommended to be designed in accordance with Section 1815 of the UBC, Voh.iine 2, Division III, 1994 edition. The rigid slab is expected to consist of a waffle slab with the slab constructed monolithically with grade beams. The structural loads carried by walls and columns will be supported by grade beams with intermediate underslab stiffeners to provide rigidity. The load bearing grade beams may be designed for an allowable soil bearing pressure of 2,000 ps£ The grade beams should extend at least 1 foot into suitable bearing existing soils and/or structural compacted fill. The design of the sla,b may be based upon the following parameters: Climatic Rating (Cw): Effective Plasticity: Soil-Climatic Factor (1--C): 19 39 0.27 Lateral Load Resistance Lateral load resistance wi-11 be developed by a combination of friction acting at the base of thickened sections and slab sections and the passive earth pressure developed by thickened sections below grade. Passive pressure and friction may be used in combination, without redtictiori, in determining the total resistance to lateral loads. A one-third increase in the passive pressure value may be used for short duration wind or seismic loads. ~-G-'--IL-E,c.--_ S_E_N_G_I_N-EE_RIN __ G_A_S_S_O_C_IA_T_E_S_, -rN-C-.-~----~----- I_ I I I I I I I I I I I I I I I I I Proposed KinderCare Learning Center Carlsbad, Ca:lifomia Project No. 2G-9907002 Page 14 A coefficient of friction of 0.20 may be used with dead load forces for footings placed on suitable bearing native soils. An allowable passive earth pressure of 200 psf per foot of footing depth below the lowest adjacent grade (pcf) may be used for the sides of thickened slab sections placed against ptoperly undisturbed native .soil or structural compacted fill continuous from suitable bearing native soils. Floor Slab Recommendations With either rigid slab foundation alternative, it is recommended that a minimum 4-inch thick granular base course be placed directly beneath the slab sections. In moisture sensitive areas and areas Where the floor will be covered with moisture sensitive materials (such as tile or carpet),. a synthetic membrane should be placed immediately below the base to serve as a vapor barrier. If the materials underlying the synthetic membrane contain sharp angles or particles, a cushion layer of sand approximately 2 inches in thickness, or a geotextile fabric, could be placed below the membrane to provide protection against puncture. In addition, the vapor barrier membrane should be evaluated for holes and punctures and the edges overlapped and taped prior to placement. It is further recommended that proper concrete curing techniques be utilized to reduce the potential development of significant shrinkage cracking or slab curling. Evaluation of Bearing Soils Soils suitable for direct foundation support or to serve as the structural fill subgrade within the foundation influence zones and for indirect foundation support should have at least a stiff comparative consistency (average qu value equal to or greater than 1.0 tsf) for cohesive (non granular) soil or a loose relative density (average corrected N-value of 8) for non-cohesive (granular soils) for the maximum recommended 2,0U0 psf soil pressure. Suitable bearing existing soils are anticipated to be encountered at a depth of approximately 1 to 2 feet below existing grade at the boring locations or at nominal depth below pad grade within structural compacted fill. However, greater depth to suitable bearing soil should be expected in localized areas due to the presence of existing fill. the suitability of the actual bearing soils must be determined by appropriate bearing capacity testing performed by a qualified geotechnical engineer during construction to verify that the foundations are supported by suitable -bearing soils. Evaluation is recommended to be performed to a depth of at least 2 equivalent footing widths or 4 feet, whichever is greater, or to a depth below the footing bearing grade as detertnined by a qualified geotechnical engineer at the time of construction. If unsuitable bearing soil is encountered they should be removed to a suitable bearing subgrade and to a lateral extent as defined in Item No. 3 of the enclosed Guide Specifications and backfilled with a structural compacted fill. Alternatively, a lean cement slurry can be used to backfill localized overexcavations. The use of a cement slurry (500 to 1,500 psi) will assist in limiting the amount of lateral overexcavation typically required utilizing a soil backfill. A relatively level bearing grade is required for the recommended foundation system. ~ GILES ENGINEERING ASSOCIATES, INC I. I I I I I I I I I I I I I I I I I I Proposed KinderCare Leaming Center Carlsbad, California Project No. 2G-9907002 Page 15 Foundation Emedment The UBC: requites a minimum 12-inch embedment depth for single story construction. However,. we recommend the perimeter thickened edge of the slab extend at least 18 inches below adjacent subgrade for bearing strength purposes and increased mo·isture protection. Additional embedment depth may be necessary for structural engjneering considerations. All footings should also be protected from weather damage both during and after construction and must be supported within suitable bearing soils as described herein. 5.7 Moderatelv Rii:id Foundation Vertical Load Capacity As an alternative to the rigid shallow foundation systems described above, the proposed building may be supported by a moderately shallow foundation system consisting of continuous strip footings for wall support and isolated square pad footings for column support. The footings anc;l slab may be constructed monolithically, thereby using a turned down slab construction technique. The use of this foundation system requires overexcavation of the existing soils and placement of a low expansive (EI less than 30) structural fill as previously described. Foundations should be founded at least 1 foot into suitable bearing structural fill placed continuous from a suitable bearing subgrade. Foundations may be designed for a maximum, net, allowable soil-bearing pressure of 2,500 pounds per square foot (psf). Minimum footing widths are recommended to be 14 and 24 inches for walls and columns, respectively. Trench footing construction is also considered suitable, provided the excavations remain stable and are allowed by the local building department. Footing Reinforcing The mrmmum steel reinforcing within continuous wall footings is· recommended to consist of at ·least six No. 5 bars (3 top artd :3 bottom) continuous through any intermittent column pad footings. The recommended reinforcing pertains to a minimum 12-inch thick, maximum 24-inch wide footing pad; additional reinforcing may be required if a thinner and/or thicker footing pad is used and/or due to structure engineering considerations. The recommended reinforcing is based upon the expansive potential of the soils which will underlie the low expansive structural fill. The actual design of foundations should be performed by a qualified structural engineer to ensure proper proportioning and reinforcing. ~ GILES ENGINEERING ASSOCIATES. IN(: I. I I I I I I I I I I I I I I I I I I Proposed KinderCare Leaming Center Carlsbad, California Project No. ZG-9907002 Page 16 Lateral Load Resistance Lateral load resistance will be developed by a combination or friction acting at the base of foundations and slabs and the passive earth pressure developed by footings below grade. Passive pressure and friction may be used in combination, without reduction, in determining the total resist?n~e to -lateral loads. A one-third increase in the passive pressure value may be used for short duration wind or seismic loads. A coefficient of friction of 0.35 may be used with dead load forces for footings placed on suitable bearing very low to non-expansive structural compacted fill soils. An allowable passive earth pressure of 225 psf per foot of footing depth below the lowest adjacent grade (pcf) may be used for the sides of footings placed against properly compacted very low to non-expansive structural fill. Bearing Material Criteria Soil suitable for direct foundation support or to serve as the structural fill subgrade within the foundation influence zone and thereby provide indirect foundation support should exhib.it at least a firm relative density (average corrected N-value of at least 10) for non-cohesive soils or stiff comparative consistency (average qu value of at least 1.25 tsf) for cohesive soils for the recommended 2,500 psf bearing capacity. Suitable bearing soils are generally anticipated to exist at nominal' depth below pad grade upon completion of the recommended building pad preparation. Structural fill placed and compacted under engineering controlled conditions is considereq to be suitable for direct foundation support. Evaluation of the foundation bearing soils is recommended to be performed by the geotechnical engineer at the time of construction prior to placement of reinforcing steel. Evalua~ion of the foundation bearing soils is recommended to be performed to a minimum depth of 4 feet or the equivalent of two footing widths below foundation bearing grade whichever is greater. The actual depth of evaluation may be revised at the discretion of the geotechnical engineer. Evaluation should consist of appropriate bearing capacity testing such as calibrated hydraulic penetrometer, Dynamic Cone Penetrometer (DCP) testing or other methods considered appropriate by the geotechnical engineer. If unsuitable bearing soils are encountered, they should be excavated to a suitable bearing soil subgrade and to a lateral extent as defined by Item No. 3 of the enclosed Guide Specifications and the excavation backfilled with a very low expansive structural compacted fill to develop a uniform bearing grade. Isolated excavations required to remove zones of unsuitable soils can also be backfilled with lean (500 to 1,500 psi) concrete slurry. Localizing thickening or stepping of footing pads is not recommended since a relatively level bearing grade is required to develop the additional rigidity provided by the increased steel reinforcing. · ~ GILES ENGINEERING A. I I I I I I I I I I I I I I I I I I Proposed KinderCare Leaming Center Carlsbad, California Project No. 20-9907002 Page 17 Foundation Embedinent The Uniform Building Code {UBC) requir~s a minimum 12-inch foundation embedment depth. However, it is recommended that exterior foundations extend at least 18 inches below the adjacent exterior grade for bearing capacity purposes. All footings must be protected against weather and water damage during and after construction, and must be supported within suitable bearing materials. Estimated Foundation Movement Post-construction total and differential movement (settlement and/or heave) of a shallow foundation system designed and constructed in accordance with the recommendations provided in this report are estimated to be less than I. I and 0.6 inches, respectively. The estimated total and differential movement is considered within tolerable limits for the proposed structures, provided that the structural design adequately considers this distortion. 5.8 Floor Slab Recommendations Subgrade , The subgrade to support a moderately rigid slab-on-grade should be prepared in accordance with the appropriate recommendations presented in the Site Development Recommendations section of this report which includes overexcavation of expansive soil and placement of low expansive structural fill. Foundation, utility trenches and other below-slab excavations should be backfilled with structural compacted fill in accordance with the project specifications. Design The floor of the proposed structure is recommended to be constructed as a moderately rigid slab-on-grade supported by a properly prepared subgrade as described above. If desired, the floor slab may be poured monolithically with perimeter foundations where the foundations consist of thickened sections thereby using a "tumed-doWn" construction technique. The slab should be· underlain by a 4-to· 6-inch thick layer of compacted coarse granular material. A synthetic sheet should be placed immediately below the floor slab to serve as a vapor barrier to protect moisture sensitive floor coverings (i.e. tile, etc.). If materials underlying the synthetic sheet contain sharp, angular particles, a cushion layer of sand approximately 2 inches thick or a geotextile should be provided to protect it from puncture. An additional layer of sand may be provided between the slab and the vapor barrier to promote proper curing. In addition, the vapor barrier sheets should be evaluated for holes and/or punctures prior to placement and the edges overlapped and taped. ~ GILES ENGINEERING AS SOCIA TES, !NC I I I I I I I I I I I I I I I I Proposed KinderCare Learning Center Carlsbad; California Project No. ZG-9907002 Page 18 Based on the recommended subgrade preparation and the anticipated live floor loading, a ~;;:i.nch thick concrete slab is recommended. Floor slab reinforcing is recommended to consist of at ···least No. 4 bars at 18-inch on-center spacings in each direction with the slab structurally connected to perimeter footings as determined by the structural engineer. The recommended minimum quantity of reinforcing is attributed to the high expansive characteristics which will underlie the newly placed structural fill. The actual design of the slab should be performed by a qualified structural engineer to ensure proper thickness and reinforcing. Proper curing techniques are recommended to reduce the potential for excessive shrinkage cracking and slab curling. Estimated Movement With proper site preparation and construction monitoring, the post-construction total and differential movement (settlement/heave) of the floor slab, constructed as recommended are estimated to be. on the order of those estimated for foundations where the floor is cast monolithically with the foundation and structurally connected. The estimated differential movement is anticipated· to occur across one-half the short dimension of the structure and is expected to be within tolerable levels provided the structural design adequate considers this distortion. 5.9 Pavement Recommendations Subgracles for New Pavement Following completion of the recommended subgrade preparation procedures, the pavement subgrade soils are expected to consist of diatotnaceous silty clay and clayey silt which are classified as a poor subgrade soils based on the Unified Soil Classification System designation of CH or MH. The general subgrade soils are anticipated to exhibit an R-value in the range of 5 to 15 when properly prepared. Since an R-value test was not included in the authorized Scope of services, an R-value of 5 has been used for p::i,vement design. The City of Carlsbad may require specific R-value testing to allow the use of the following design section or may specify a code section in lieu of R-value testing; To use this R-value, all fill added to the . pavement subgrade must have pavement support characteristics at least equivalent to the existing soils, and must be placed and compacted in accordance with the project specifications. I ~ GILES ENGINEERING ASSOC! . I I 1. I I I I I I I I I I I I I I Proposed KjnderCare Leaming Center Carlsbad, California Project No. 2G-9907002 Page 19 Asphalt Pavements The following table presents the recommended pavement section consisting of asphaltic concrete over a granular base, along with the appropriate CAL TRANS specifications for proper materials and placement procedures. An alternate pavement section has been provided for use in parking stall .areas due to the anticipated lower traffic intensity in these areas. However, care must be used so that truck traffic is excluded from areas where the thinner pavement section is used, since premature pavement distress may occur. In the event that heavy· vehicle traffic cannot be excluded from the specific areas, the pavement section recommended for drive areas should be utilized throughout the parking lot. ASPHALT PAVEMENTS Materials Thickness (inches) CALTRANS Parking Stalls Drive Lanes Specifications Asphaltic Concrete 1 1 Section 39, (a) Surface Course (b) Asphaltic Concrete 2 2 Section 39, (a) Binder Course (b) Crushed Aggregate 7 10: Section 26, Class II Base Course (R-value at least 78) NOTES: (a) Compaction to density between 95 and 100 percent of the 50-Blow Marshall Density (b) The surface and binder course may be combined as a single layer placed in one lift if similar materials are utilized. Pavement recommendations are based upon CAL TRANS design parameters for a twenty- year design life and assume proper drainage and construction monitoring. It is, therefore, recommended that the geotechnical engineer monitor and test subgrade preparation, and that the subgrade be evaluated immediately before pavement. construction. Construction of new pavement on an expansive soil subgrade should not be considered free of risk. Increased pavement maintenance and periodic repairs should be expected due to the presence of expansive so.ils. Pavement rehabilitation at 8-to 9-year intervals should be anticipated to achieve a 20-year design life. I ~ GILES ENGINEERING ASSOCIATES, I· I· I I I I I I I I , I Proposed KinderCare Leaming Center Carlsbad, California Project No. 2G-9907002 Page 20 Concrete Pavements Considering the higher pavement stress in the trash enclosure loading zone, a 7-inch thick, properly reinforced concrete pavement underlain by a: 4-inch compacted coarse granular base placed on a properly prepared subgrade should be considered. Minimum reinforced within_ conci;ete pavements is recommended to consist of heavy welded wire mesh (6x6-W2.9xW2.9 WWM). Materials and construction procedures for concrete pavements should be in accordance with Section 40 of the CALTRANS Standard. I I I ~ GILES ENGINEERING ASSOCIATES, INC I I I I I I I I I I I I I I I I I I I APPENDIX.A PROJECT DETAILS The information enclosed herein proVIdes a brief description of asswned project details. If, however, the actual details are different than the asswned details, Giles must be notified, since changes and/or additions to the geotechnical recommendations may be necessary. GILES ENGINEERING ASSOCIATES, INC. I 1· I I I I I I I I I I I I I I I I I Building PROPOSED KINDERCARE LEARNING CENTER CARLSBAD, CALIFORNIA PROJECT DETAILS The proposed structure will consist of a one-story child care center of wood frame or masonry construction with a wood truss roof system supported by exterior and/or interior bearing walls and possibly isolated columns. The maximum combined dead and.live loads supported by the bearing walls and columns is assumed to be 2,000 pounds per linear foot (plf) and 30,000 pounds~ respectively. The live load_ supported by the floor slab will be a maximum of 100 pounds per square foot (psf). Pavement Pavement design has been based upon a Traffic Index (TI) of 5.0 and 4.0 for drive lane and parking stall areas of the parking lot, respectively. The pavement sections are based on a 20-year service life. ~--.a-· _G.;,_I_L_E_S_E_N_G_IN_E_E_RIN_G---'-A-S-SO_C_I_A..,....,T,....,.E_S_, JN-. ...,..C-. ----------- I I I I I I I. ,· I I I I ·I I I I I I I I TABLE OF CONTENTS GEOTECHNICAi ENGINEERING EXPLORATION AND ANALYSIS Proposed KinderCare Learning Center Melrose Drive and Carrillo Way Carlsbad, California Project No. 20-9907002 Description COVER LETTER ................................................................................................................ I 1.0 EXECUTIVE SUMMARY OUTLINE .......................................................................... 1 2.0·SCOPE OF S·ERVICES ................................................................................................. 3 3;0 SITE AND PROJECT DESCRIPTION ......................................................................... 3 3.1 Site Description .......................................................................................................... 3 3.2 Proposed Project ......................................•................................................................. 3 4.0 SUBSURFACE EXPLORATION ................................................................................. 4 4.1 Subsurface Exploration .............................................................................................. 4 4.2 Subsurface Conditions ................................................................................................ 4 5.0 CONCLUSIONS AND RECOMMENDATIONS ........................................................ 6 5.1 Soil Vapor Scan ......................................................................................................... 6 5.2 Seismic Design Considerations .................................................................................. 6 5.3 Geotechnical Design Considerations ......................................................................... 7 5.4 Site Development Recommendations ........................................................................ 8 5.5 Site Development Considetations .............. ~ ............................................................. 11 5.6 Rigid Foundation Altematives.; ............................................................................... 12 5.7 Moderately Rigid Foundation .................................................................................. 15 5. 8 Floor Slab Recommendations .................................................................................. 1 7 5.9 Pavement Recommendations ........•........................................................................... 18 Appendices: Appendix A: Project Details Appendix B: Figures (4) and Test Boring Logs (7) Appendix C: Field Procedures Appendix D: Laboratory Testing and Soil Classification Appendix E: · General Information (Modified Proctor Procedures) © Giles Engineering Associates, Inc. 1999 I, I I I I I I I I I I I I I !I I I .... APPENDIX B FIGURES AND TEST BORING·LOGS The Boring Location Plan contained herein was prepared based upon information supplied by Giles' client, or others, along With Giles' field measurements and observations. The diagram is presented for conceptual purposes only and is intended to assist the reader in report interpretation. The Test Boring Logs and related information enclosed herein depict the subsurface (soil and water) conditions encountered at the specific boring locations on the date that the exploration was performed. Subsurface conditions may differ between boring locations and within areas of the site that were not explored with test borings. The subsurface conditions may also change at the boring locations over the passage of time. GILES ENGINEERING ASSOCIATES, INC. -,_ , .. ,_ -· -·11111.--.-----,_ ... -·----NOTE: Dimensions indicate an approximate method of locating test borings in the field with respect to existing curb.an property lines. This plan is adapted from plans supplied ·by the client. Melrose Drive ..----Elevation 74.71 SCALE: 1 inch= 50 feet (S)N Temporary Benchmark--~ 45' 40' 53' 143' Top of Curb 45' Assumed Elevation - FIGURE NO. 1 TEST BORING LOCATION PLAN Proposed Kindercare Learning Center SWC of Melrose Drive and Carrillo Way Carlsbad, California Project No. 2G-9907002 -----·-ti'"•··-·-··-----·--··-.--· 67' t___ n ~~ n Proposed Building -:-:~ l . Area \._ ./ ~~~ c-:, -~-.:1 __ _ , , .( n Ill ~ .... f-1 f-1 0 ~ ~ ~ GILES E::NGINEEfllN<, Assoc1A1 ES. INC. I I I I I, I I I I I I I I I I I I I I · Consolidation/Collapse Test Results 0 2 3 .5 4 ~ (/) C .!2 -5 ni :2 ~ 6 C 0 CJ 7 8 9 I I I I I [ 10 0.01 • r--.. t---.. . . 0.1 ~ ...... "'~ \ \ .. '\ t \ '\ \ ' . 10 Normal Pressure (ksf) Classification: Yellow Brown diatomaceous Clayey Silt Boring Number: 1 Initial Moisture Content(%) Sample Number: 3 Final Moisture Content(%) Depth (ft) 3 to 4 Initial Dry Density (pcf) Liquid Limit 46 Final Dry Density (pcf) Plastic Limit 16 Water added at (psf) Specimen Diameter (in) 2.4 Percent Collapse (%) Specimen Thickness (in) 1.0 FIGURE 2 CONSOLIDATION/COLLAPSE TEST RES UL TS Proposed Kinder Care 100 24.2 97.2 1600 1.35 Carlsbad, California Project No. 2G-9907002 ~ GILES €NGINEERING AssocrATES, rNC. ,._ I I I . I I I I I I I I I I I I .I I I 0 1 2 3 .!: 4 f! w § 5 ::: c,s :E g 6 C 8 7 8 9 '.__ 10 0.1 - .. Consolidation/Collapse Test Results -. --·r-1 t,....,_ ~--~ l'a. "' I'\. ~ ., 1 Normal Pressure (ksf) Classification: Light Gray Brown diatomaceous Clayey Silt Boring N1.,1mber: 3 Initial Moisture Content(%) Sample Number: 3 Final Moisture Content (%) Depth (ft) 3 to 4 Initial Dry Density (pcf) Liquid Limit 54 Final Dry Density (pcf) Plastic Limit 23 Water added at (psf) Specimen Dic;3meter (in) 2.4 Percent Collapse (%) Specimen Thickness (in) 1.0 FIGURE 3 ~ 10 22.1 31.4 98.2 99.8 1600 -0.08 coNsouoATI0N1coLLAPSE TEST RESUtTS r A Proposed Kinder Care . \..71LE:S C.,NGINE:E:RING SSOCl~TE:S. INC. Carlsbad, California GEorE:CHNICAl, E:NIJIRONME:NTAL Project No. 2G-9907002 AND C0Nmua1on MATERIAL, ConrnLTANT, ------... ---------__ .. .. --.. U S ST ANOAAD SIEVE OPENING IN INCHES U.S. STANDARD SIEVE NUMBERS HYOAOMETER e 4 3 2 11't 1 % l't ¼ 3 4 e a 10 , .. 1a 20 30 40 50 70 100 140 200 0 100 I I 11 I II I II I I I I II 1-r--! r-'.. I ,I I I I I I I I ..... t--, I It J 10 90 I I II , 1--..1, I I I I I ·1 ' I, I I I',,. 20 80 I I ·' I I I I ...... ;1 I I . I .'-... 11 ' 70 II I 30 I I ~ II I I . !i: ... II I I ' I\. Cl :I: I iii !2 80 -11 ~, 40 3l Ill I I ' >-3l I I I ~ -> I ii " I • :5 50 II I I 50 ~ z I I II . "· ii: I I 0 I, I u i I -7 I'\. ... I I. I z U 40 I, ,. 60 ~ i II I :5 II I I 11 ... I I .. I I ' I, 70 30 II 1• I II II I I i I I II I 20 80 -11 I II I I I, I I I, I 1 I 90 I I i I . II II ' I 0 II· It I 11 100 500 100 50 10 5 1 0.5 0.1 005 0.01 0.005 0.001 GRAIN SIZE IN MIWMETEAS I COBBLES I GRAVEL I SAND SILTOACLAY I COARSE I FINE I COARSE I MEDIUM FINE Boring No Sample No Elev or Deplh C1a,!lillcallon Nalw'Mo LL PL Pl 3 3 3 to 4 LiRht Gravish Brown 22 54 23 31 G1Le:s E°:NGINE:E:RING AssoCIN'E:S diatomaceous Clayey Silt Propose« KinderCare Learning Cente Carlsbad. California REPORT OF SOIL ANALYSIS Project No. 2G-9907002 FIGURE 4 1-, I I I I I I I I I I I I I I I I I I . . . ,RECORD OF SUBSURFACE EXPLORATION BOR1 IN(i.Q~Q. &J.QCAT!QN: Nt: t:3Ullding corner) SURFACE ELEVATION: ---- PROJECT: Propose9 KinderCare ; PROJECT LOCATION: ---. ----------- 66.6 . COMPLETION DATE: - Melrose Drive and Carrillo Way --------------------" -- 7/6/99 FIELD REPRESENTATIVE: --- _______ _farlsbad, O~lifdrnia ______ _ Rich Koester PROJECT NUMBER: 2G-9907002 Below No.& u q qs GILES ENGINEERIN ASSOCIATES, INC. Dallas Madison Atlanta Milwaukee Los Angeles Washington, O.C. Seattle w I Feet Sample l N J q MATERIAL bESCRIPTiON (tlf) PIO NOTES Surface Type per 12" (tsf) (tsf) (%) · ? inch thir.k Root M::it 1-Au· - ,_ Light Grayish Brown diatomaceous Clayey Silt -,___ ,_ Moist .(Fill) 2-CS 18 4.5+ 19 BDL Dd=99 NOTEA Yellowish Brown diatomaceous Clayey Silt._ · 3-CS 17 3.5 24 BDL Dd=93 ~ Moist See Figure 2 Light Brown diatomaceous Clayey Silt with -Yellowish Brown Silty fine to medium Sand 5 4-CS 19 4.5+ 21 BDL Dd=97 lenses -Damp (Fill) Dark Yellowish Brown Clayey fine to medium 5-CS 15 17 BDL Dd=103 --Sand with Light Olive Grayish Brown 23 · diatomaceous Clayey Silt -Moist (Fill) Dark Yellow to Grayish Brown Silty fine Sand I 6-CS 17 17 BDL Dd=103 '"9 10 -- -Light Grayish Brown Clayey Silt with Orangish ,_ Brown Silt lenses -Damp to Moist - '--7-SS 36 15 BDL .. ,.. Boring Termi.nated at 15' ,T·1oo1 NOTE A: Expansion Index (El) test performed per UBC Standard No. 18-2 on composite sample to 5 feet. EI=105 Dd=98 pc;f i ' f I ! i I I w=13% I Atterberg Limits: LL=54 Pl=35 I WATER OBSERVATION DATA I REMARKS -~ WATER ENCOUNTERED DURING DRILLING:None j 'ii-WATER LEVEL AFTER REMOVAL: Dry ~ -CAVE DEPTH AFTER REMOVAL: 10 ft. ,._ _y WATER LEVEL AFT~R HOURS: ~ ::iiiii CAVE DEPTH AFTER HOURS; Changes In strata indicated by the lines,are approximate boundaries between soil types. The actual transition may be gradual and may vary considerably between be.rings. Location of Test Boring is shown on the Boring Location Plan. I i J 1 ! ! I J ! I I i ! ! I I I I I I I I I I I I I I· I I I I I I I I I I .RECORD OF SUBSURFACE EXPLORATION so2Rl~Gll0.: &J .. QCATLON: ) l t;I:: t:Sulldmg c.;orner SURFACE ELEVATION:' - 72.4 COMPLETION DATE: 7/6/99 FIELD REPRESENTATIVE: --- Rich Koester PROJECT: . . . Proposed KinderCare . PROJECT LOCATION: ------------ -____ Melrose Drive and Carrillo Way ____ _ Carlsbad, California -----.----.-----.------ PROJECT NUMBER: _ 2G-9907002 Feet q qs Below No.& u GILES ENGINEERIN ASSOCIATES, INC. Dallas Madison ·Atlanta Milwaukee Los Angeles Washington, D.C. Seattle w Sample i N J q MATERIAL DESCRIPTION (tff} PIO NOTES Surfa~ . Type per 12" (tsf} (tsf} (%) ~ inr.h Root M::it 1-AU - ,_ Light Grayish Brown diatomaceous Clayey Silt, ,__ '-trace Organic Matter (Fibers) -Damp (Fill) 2-SS 12 4.5+ 15 SOL - ,_ - ,_ -3-SS 18 4.5 ·22 SOL --Moist 5 Light Gray Clayey fine to medium Sand -Damp 4-SS . 34 10 BDL ,_ - ,_ -I ,_ -5-SS 17+30 13 BDL I I i -10 I -fine to medium Sandy Clay -Moist ..... - -- --I 6-SS 17 l --38 BDL I ! ~~ l Boring Terminated at 15' ..., I ! ! I ' I ' : ! ' I i i ' l ' ! ! : I ' WATER OBSERVATION DATA REMARKS I ' 'fl. WATER ENCOUNTERED DURING DRILLING:None ; ....--,. ' '5l. WATER LEVEL AFTER REMOVAL: Dry ' -; -CAVE DEPTH AFTER REMOVAL: 13.5 ft. I ,___ ! .....!.... WATER LEVEL AFTER HOURS: ) '.iiiiiii CAVE DEPTH AFTER HOURS: i ! Changes In strata Indicated by the llnea are approximate boundaries between soil types. The actual transition may be gradual and may vary considerably between borings. Location of Test Bonng is shown on the Boring Location Plan. · · I I I 1· I I I ,I I • I I I I I I I I I I I· I , RECORD OF SUBSURFA-CE EXPLORATION ~ sog1~08& rr8CATl8N: ) P~OJECT: u1 mg orner Proposed t<inderCare --------------SURFACE ELEVATION: ~PROJECT LOCATION: ------. --------- 72.6 ._ _____ Melrose Drive and Carrillo W~ _____ GILES ENGINEERING COMPLETION DATE: ----ASSOCIATES, INC. 7/6/99 Carlsbad, California Dallas Madison Atlanta 1---------' -------------------------. ---Milwaukee Los Angeles 'FIELD REPRESENTATIVE: Rich Koester PROJECT NUMBER: 2G-9907002 Washington, D.C. Se~ttle Feet Sample N l q q qs MATERIAl,. DESCRIPTION Below No.& per12" (~f) ctffl w PIO NOTES Surface Type. (tsf) (%) 1-AU Light Grayish Brown diatomaceous Clayey Silt - Moist (Fill} 2-CS 20 4.5+ 19 BDL Dd=97 3-CS. 18 3.5 23 BDL Dd=97 -Very. Moist See Figure 3 Gray diatomaceous Clayey Silt, little Orangish Brown mottling -Damp (Possible Fill} 5 4-CS 30 . 4.5'1-16 BDL Dd=108 Gray and Orahgish Brown mottled 5-CS 18 4.5+ 18 BDL Dd=101 diafomaceous Clayey Silt -Damp (Possible Fill) 6-CS 24 4.5+ 14 BDL Dd=104 10 Light Grayish Brown, slightly Orangish Brown mottled Silty Clay -Moist · · 7-SS 18 4.2 22 BDL 15 Light Gray Clayey Silt -Damp 8-SS 43 4.5+ 19 BDL Boring Terminated at 20' WATER OBSERVATION DATA REMARKS 5l. WATER ENCOUNTERED DURING DRILLING;None ~ WATER LEVEL AFTER REMOVAL: Dry CAVE DEPTH AFTER REMOVAL: 18.5 ft . .,: WATER LEVEL AFTER HOURS: CAVE DEPTH AFTER HOURS: Changes in strata indicated by the lines are approximate boundaries betwBBn 1oil types. The actual transition may be gradual and may vary considerably betwBBn boring,. Location of Test Boring Is shown on the Boring Location Plan. I I I I I 1. I I I I I I I I I I I I I :I I I I I ,RECORD OF SUBSURFACE EXPLORATION BORINQ.NO. & LOGAJIQINd·:. ) 4 (<.;enter ct BUI mg PROJECT: - Proposed KinderCare . SURFACE ELEVATION: . . PROJECT LOCATION: --------------- 67.6 COMPLETION DATE: 7/6/99 FIELD REPRESENTATIVE: --- Rich Koester _____ Melrose Drive and Carrillo Way ____ _ Carlsbad, California ------. ------. __ , __ ~ ---- PROJECT NUMBER: ZG-9907002 Sample No.& GILES ENGINEERIN ASSOCIATES, INC. Dallas Madison Atlanta Milwaukee Los Angeles Washington, D.C. Seattle w I Feet N J qu qP. I qs MATERIAL DESCRIPTION Below PIO NOTES · Surface Type per 12" (tsf) (tsf) (tsf) (%) 7? inr.h Rnnt M::it 1-AU - -Dark Yellow t9 Grayish Brown diatomaceous ,--- Clayey Silt, little Yellow fine to medium Sand -2-SS 11 20 BDL -Damp (Fill) - -Light Grayish Brown diatomaceous Silty Clay - -Moist (Fill) -3-SS 11 2.7 ·19 SOL LL=50, P1=23 (CH) ... 5 ... 4-SS 10 4.2 19 BDL --'- -Light Grayish Brown diatomaceous Clayey Silt --with Orangish Brown Silty fine Sand lenses, -5-SS 16 3.7 19 BDL trace Organic Matter (fibers) at 1 O feet -Moist 10 -(Fill) -- ,.... - -- I--6-SS 9+25 16 BDL. ... Light Gray to Yellowish Brown Clayey fine to medium Sand -Damp 15 -- -- -Dark Olive Grayish Brown fine to coarse Sand - :... Damp (Weathered Sandstone) 7_r•c;: 50/4 12 BDL -20- I-- -- -- ,.... -8-$5 94/8 9 BDL I --Boring Terminafed at 25' -- I I I WATER OBSERVATION DATA REMARKS '¥-I WATER ENCOUNTERED DURING DRILLING:None -:I-WATER LEVEL AFTER REMOVAL: Dry --CAVE DEPTH AFTER REMOVAL: 17 ft. -.Y WATl;R LEVEL AFTER HOURS: --=-- .-iii CAVE DEPTH AFTER HOURS: . -.. Changes in strata indicated by the lines.are approximate boundaries between soil types. The actual transition may be gradual and may vary considerably between borings. Location of Test Boring ia shown·on th\l Boring Location Plan. . I I I I I I I I I I I I I I I I I I I I I .RECORD OF SUBSURFACE EXPLORATION BO.RING ~PB& I.Q~ATIQN: ) 5 lNVV u1ldmg corner SURFACE ELEVATION; 66.3 . COMPLETION DATE: . 7/6/99 FIELD R~PRESENTATIVE: Rich Koester PROJECT: . Proposed Kinde·rcare , PROJECT LOCATION: --------------- _____ Melrose Driv~ and Carrillo Way ____ _ _______ Carlsbad, California ______ _ PROJECT NUMBER: 2G-9907002 GILES ENGINEERIN ASSOCIATES, INC. Dallas Madison Atlanta Milwaukee L,os Angeles Washington, D.C. Seattle MATERIA~ DESCRIPTION Feet Sample N l qu q qs I Below No.& (Jf} w PIO NOTES Surfa~ . T,ype per 12" (tsf} (tsf} (%) !........d inch Root Mat r 1-AU - -Light Gray Clay, trace Organic Matter (fibers) -- _ Moist (Fill) 2-SS 9 4.5 22 BDL - -Light Grayish Brown diatomaceous Clayey Silt, -few Dark Brown Silty Clay lenses -Moist (Fill) -3-S$ 19 . 4.5+ 16 BDL ~ 5 '""' 4-SS 19 . 4.5+ 21 BDL -- -Dark Yellowish Brown diatomaceous Clayey ..... Silt, some fine to medium Sand -Moist (Fill) -5-:SS 15 4.5+ 13 BDL -10 '""' - '""' - '' -· Dark 'Brown Silty Clay, trace Organic Matter -(Roots) -Damp (Possible Fill) -6-SS 17 9.0 17 BDL ~ 15 · '""' - -- -Dark Yellowish Brown to Orangish Brown fine to 7-SS 56 13 BDL -medium Sand, little Clay -Damp (Highly - We.athered Sandstone) "" Boring Terminated· at 20' -- WATER OBSERVATION DATA REMARKS 'Sl-'WATER ENCOUNTERED DURING bRILLING:None ---51-WATER LEVEL AFTER REMOVAL: Dry --CAVE DEPTH AFTER REMOVAL: 18.5 ft. ' I--- .Y WATER LEVEL AFTER HOURS: ~ :-:;;; CAVE DEPTH AFTER HOURS: Changes m strata indicated by the.fines are approximate boundariea between 101I types. The actual transition may be gradual and may vary con11derably between borings. Location of Test Bonng Is shown on the Boring Location Plan. I ! i I ! j ! ! ! ' ' ' ! I i I ' I I i I I ! I I i I I I I I I I I I I I I I I I I I I I I I I I I ,RECORD OF SUBSURFACE EXPLORATION BOR~rsf ~~&9~ Tl~ea) PROJECT: 9 . Proposed KinderCare SURFACE ELEVATION: ---.... PROJECT LOCATION:----------. --- 73.8 Melrose Drive and Carrillo Way COMPLETION DATE:-----·'-. -----. ---------. ------· ,__ --"--_!.~99 ___ --+-______ _g~lsbad!....Californiij ~-_____ 1 , FIELD REPRESENTATIVE: / Rich Ko.ester I PROJECT NUMBER: 2G-9907002 MATERIAL 0ESCRIPTION h4 inch Root Mat 1-AU .. I - ,_ Light Grayish Brown diatomaceous Silty Clay, .,__ 2-SS 14 4.5 ._ some fine to medium Sand; Dark Brown Clayey - Silt little fine Sand -Damo (Fill\ -Light Grayish Brown diatomaceous Silty Clay to --Clayey Silt -Very Moist (Fill) -3-SS 15 2.5 -Boring T ermmated at 5 ' .., 1. 1 i I I i i GILES ENGINEERING ASSOCIATES, INC. Dallas Madison Atlanta Milwaukee Los Angeles Washington, D.C. Seattle 12 BDL 23 BDL WATER OBSERVATION DATA I I REMARKS 1 )... j WATER ENCOUNTERED DURING DRILLING:None ' : ';/. I WATER LEVEL AFTER REMOVAL: Dry : -I CAVE DEPTH AFTER REMOVAL: 3.5 / ~ I WATER LEVEL AFTER HOURS: i ..,..j CAVE DEPTH AFTER HOURS: . Changes in strata indicated by the lines are approximate boundaries between ~oil types. The-actual transition may be gradual and may vary considerably between borings. Location of Test Boring is shown on the Boring Location Plan. I I I I I I I I I I I I I I I I I I I ,.RECORD OF SUBSURFACE EXPLORATION ~ BO~rsw ~ LOifAT10A1: ) PROJECT: ar mg rea Proposed KinderCare SURFACE ELEVATION: -J.-----------·-------------~ PROJECT LOCATION: ______ 75.3 __ . __ f _____ Melrose Drive and Carrillo-Way. ____ . GILES ENGINEERING COMPLETION DATEr · ASSOCIATES, INC. 7/6/99 . · . Carlsbad, California Dallas Madison Atlanta FIELDREPRESENTATIVE: -----------------------Milwaukee Los Angeles Rich Koester . . PROJECT NUMBER: . 2G.;990700? . Washington, D.C. Seattle MATERIAL DESCRIPTION I :e~~~ I s~:~e I N I qu J qp I qs I w I PIO ! 1 NOTES 1 Surface · Type ~per 12"~ (tst) I (tst) 1 (tst) ! (%) . n4 inr.h Rnnt M::1t ,_ Light Gray diatomaceous Clayey Silt -Very ,_ Moist (Fill) · Brown Silty Clay With Dark Brown Silty Clay to r Clayey Silt -Moist (Fill) I i i I I i. l I Boring Terminated ~t 5' WATER OBSERVATION DATA I I- -.., l ~ ; WATER ENCOUNTERED DURING DRILLING:None :l. ! WATER LEVEL AFTER REMOVAL: Dry :-/ CAVE DEPTH AFTER REMOVAL: 3.5 . ,---; : .:t: I WATER LEVEL AFTER HOURS: ! ..:..1 CAVE DEPTH AFTER HOURS: I 1-AU - 2-SS 6 3,0 25 SOL - - -3-SS 11 4.5+ 18 SOL REMARKS Changes iii strata indicated by the linH are approximate boundaries between·so11·typea. The actual transition may be gradual and may vary considerably between borings. Location of Teat Boring i1 shown on th1 Boring-Location Plan, · I I I I I I I I I I I I I I . I I I !I I AP.PENDIX C FIELD PROCEDURES The field operations were conducted in general accordance with the procedures recommended by the American Society for Testing and Materials (ASTM) designation D 420 entitled "Standard Guide for Sampling Soil and Rock" and/or other relevant specifications. Soil samples were preserved and transported to Giles' laboratory in general accordance with the procedures recommended by ASTM designation D 4220 entitled "Standard Practice for Preserving and Transporting Soil Samples." Brief descriptions of the sampling, testing and field procedures commonly performed by Giles are provided herein. GILES ENGINEERING ASSOCIATES, INC. 1. I I I I I I I I I I I· I I I I I I I FIELD SAMPLIN9 AND TESTING PROCEDURES Auger Sampling (AU) Soil samples are removed from the auger flights as an auger is withdrawn above the ground surface. Such samples are used to determine general soil types and identify approximate soil stratifications. Auger samples are highly disturbed and are therefore not typic3:ily used for geotechnical strength testing. Split-Barrel Sampling (SS) -(ASTM D-1586) A split-barrel sampler with a 2-inch outside diameter is driven into the subsoil with a 140-pound hammer, free-falling a vertical distance of 30 inches. The summation of hammer-blows required to drive the .sampler the final 12 inches of an 18-inch sample interval is defined as the "Standard Penetration Resistance" or "N-value." The N-value is representative of the soils' resistance to penetration. The N-value is therefore an index of the relative density of granular soils and the comparative consistency of cohesive soils. A soil sample is collected from e.ach SPT interval. Shelby Tupe Sampling CST) -CASTM D-1587) A relatively undisturbed soil sample is collected by hydraulically advancing a thin- walled Shelby Tube sampler into a soil m,ass. Shelby Tubes have a sharp cutting edge and are commonly 2 to 5 inches in diameter. Unless otherwise noted, Giles uses 3-inch-diameter tubes. Bulk Sample <BS} A relatively large volume of soil is collected with a shovel or other manually- operated tool. The sample is typically transported to Giles' materials laboratory in a sealed bag or bucket. Dynamic <;one Penetration Test <DC) -<ASTM STP 399) This test is conducted by driving a 1.5-inch-diameter cone into the subsoil using a 15-pound steel ring (hammer), free-falling a vertical distance of 20 inches. The number of hammer-blows required to drive the cone 1 ¾ inches is an indication of the soil strength and density, and is defined as "N." The Dynamic Cone Penetration test is commonly conducted in hand auger borings, test pits and within excavated trenches. -Continued ·- GILES ENGINEERING ASSOCIATES, INC. I- I I- I- I I I I I I I I I I I I I I I Ring-Lined Barrel Sampling -(ASTM b 3550) In this procedure, a ring-lined barrel sampler is used to collect soil samples for classification and laboratory testing. This method provides samples that fit directly into laboratory test instruments without additional handling/disturbance. Sampling and Testing Procedures Th~ field testing and sampling operations were conducted in general accordance with the procedures r~commended by the American Society for Testing and Materials (ASTM) and/or other relevant specifications. Results of the field testing (i.e. N-values) are reported on the Test Boring Logs. Explanations-of the terms and symbols shown on the logs are provided on the appendix enclosure entitled "General Notes." GILES ENGINEERING ASSOCIATES, INC. I- I I I I I I I I I I I I I I I I I I APPENDIX D . LABORATORY TESTING AND CLASSIFICATION The laboratory testing was conducted under the supervision of a geotechnical engineer in general accordance with the procedures recommended by the American Society for Testing and Materials (ASTM) and/or other relevant specifications. Brief descriptions of laboratory tests commonly performed by Giles are provided herein. GILES ENGINEERING ASSOCIATES, INC. I- I I I- I I I I I I I I I I I I I i I I LABORATORY TESTING AND CLASSIFICATION Photoionization Detector (PID) ln this procedure, soil samples are "scam:1ed" in Giles' analytical laboratory using a Photoionization Detector (PID). The instrument is equipped with an 11.7 eV lamp calibrated to a Benzene Standard and is capable of detecting a minute concentration of certain Volatile Organic Compound (VOC) vapors, such as those commonly associated with petroleum products and some solvents. Results of the l>ID analysis are expressed in HNu (manufacturer's) units rather than actual concentration. Moisture Content (w) (ASTM D 2216) Moisture content is defined as the ratio of the weight of water contained within a soil sample to the weight of the dry solids within the sample. Moisture content is expressed as a percentage. Unconfined Compressive Strength (qu) (ASTM D 2166) An axial load is applied at a uniform rate to a cylindrical soil sample. The unconfined compressive strength is the maximum stress obtained or the stress when 15 % axial strain is reached, whichever occurs first. Calibrated .Penetrometer. Resistance (Qp) The small, cylindrical tip ofa hand-held penetrometer is pressed into a soil sample to a prescribed depth to measure the soils capacity to resist penetration. This test is used to evaluate unconfined compressive strength. Vane-Shear Strenitl) <qs) The blades of a vane are inserted into the flat surface of a soil sample and the vane is rotated until failure occurs. The maximum shear resistance measured immediately prior to failure is taken as the vane-shear strength. Loss-On-I~ition (ASTM D 2974: Method C} The Loss-On-Ignition (L.0.1.) test is used to determine the organic content of a soil $ample. This procedure is conducted by heating a dry soil sample to 440°C in order to burn- off or "ash" organic matter .present within the sample. The L.0.1. value is the ratio of the weight lost due to ignition compared to the initial weight of the dry sample. L.O.I. is expressed as a percentage. GILES ENGINEERING ASSOCIATES, INC. I- I .. I I I I I I I I I I I I I I I I I Particle Size Distribution CAST;ryf D 421, D 422, and D 1140) This test is performed to determine the distribution of specific particle sizes (diameters) within a soil sample. The distribution of coarse;..grained soil particles (sand and gravel) is determined from a "sieve analysis," which is conducted by passing the sample through a series of nested sieves. The distribution of fine-grained soil particles (silt and clay) is determined from a "hydrometer analysis," which is based on the sedimentation of particles suspended in water. Consolidation Test (ASTM D 2435} In this procedure, a series of cumulative vertical loads are applied to a small, lateral ly confined soil sample. During each load increment, vertical compression ( consolidation) of the sample is measured over a period of ti.Jn_e. Results of this test are used to estimate settlement and time rate of settlement. Classification of Samples Each soil sample was visually-manually classified, based on texture and plasticity, in general accordance with the Unified Soil Classification System (ASTM D-2488-75). The classifications are reported on the Test Boring Logs. Laboratory Testin~ The laboratory testing operations were conducted in general accordance with the procedures recommended by the American Society for Testing and Materials (ASTM) and/or other relevant specifications. Results of the laboratory tests are provided on the Test Boring Logs or other appendix enclosures. Explanation of the terms and symbols used on the logs is provided on the appendix enclosure entitled "General Notes." GILES ENGINEERING ASSOCIATES, INC. I I I I I I I I I I I I I I I I- I I I California Bearing Ratio (CBR} Test ASTM D-1833 The CBR test is used for evaluation of a soil subgrade for pavement design. The test consists of measuring the force required for a 3-square-inch cylindrical piston to penetrate 0.1 or 0.2 inches into a compacted soil sample. The result is expressed as a percent of force required to penetrate a standard compacted crushed sto:p.e. Unless a CBR test has been specifically requested by the client or heavy traffic loads are expected, the CBR is estimated from published charts, based on soil classification and strength characteristics. A typical correlation chart is indicated below. c:&1.i FOIIHI.& • AIIING IIATIO-CINI' 2 3 A 5 g 7 I 9 10 15 Z0 Z5 30 <IC ,o 10 ,a 10 ,o 100 ' ' I I . I I I I I I I ! I I I I ASTM son. a..t.SSFtC.ITIOI< STSTEII. G• Gw :I: ·-Clell!ficet-l' I -I I I I ~ "' 100 I I i -"" .. .. I I " -~ I I I = ..... I I I I I I I I I I I I I I I AA$NT0 SOIL ~A$$9'1CATIOH I I I I I I I ...... , ..... l•• ·-~-~ ...... ••'l•7 l ·-·-· I ·-~ I ,, I . . I .. . .. ! ,'. ' ,, I I I I I I I l I ' I I I I I '1llDIAI. -.&TION Al)MIIOISTIIATIOH .. SO&. a..t.SSIFICATIOfl I .. = j I I 1 I ·-· = I I ....• - I I I . ... -6 . . I ! I ·-· I I ··~ . = I ·-~ I I i ' -·· I -=•t:JI' l ! 5 la '~ I I I I : ' I I I I IIUisT.uc:E. -IIE -.II· ! I I I ~ ''° . :so I 30 7'0 i I I I . ' T I. I I i : .1 I , , .. ~~5 ~F ~IUD[ ~,cno,! •C ~11 fl!II ~ 1 I I sool l i •=!0 I I ! 200 I m ioo.1 I A00 ,00 ! I I . I I I : ! I I I l I i IE&IINIG~.~1 I ! I I i a 2:0 ~ A() ':0 '° I I I I I . I I I I I I ~"~ ~ IIATI0 .. /:111 I • ' _I -' • l l i 3 • 5 ' 7 'I 9 10. 15 ZD ~ lO A() . ~ '° 70 a:, '° l00 GILES ENGINEERING ASSOCIA 'fES, INC. I I I I I I I I I I I I I I I I I I I APPENDIX E GENERAL INFORMATION . GILES ENGINEERING ASSOCIATES, INC. I- I I I I I I I I I I I I I I I I I I GENERAL COMMENTS The soil samples obtained during the subsurface exploration will be retained for a period of thirty days. Jf no instructions are received, they will be disposed of at .that time. · This report has been prepared exclusively for the client in order to aid in the evaluation of this property and to a$Sist the architects and engineers in .the design and preparation of the project plans and specifications. Copies of this report may be provided to contractor(s), with contract documents, to disclose information relative to this project. The report, however, has not been prepared to serve as the plans and specifications for actual construction without the appropriate interpretation by the project architect, structural engineer, and/or civil engineer. Reproduction and distribution of this report must be authorized by the client and Giles. This report has been based on assumed conditions/characteristics of the proposed development where specific information was not available. It is recommended that the architect, civil engineer and structural engineer along with any other design professionals involved in this project carefully review these assumptioI1S to ensure they are consistent with the actual planned development. When discrepancies exist, they should be brought to our attention to ensure they do not affect the conclusions and recommendations provided herein. The project plans and specifications may also be submitted to Giles for review to ensure that the geotechnical related conclusions and recommendations provided herein have been correctly interpreted. The analysis of this site was based on a subsoil profile interpolated from a limited subsurface exploration. If the actual conditions encountered during construction vary from those indicated by the borings, Giles must be contacted immediately to detemtine if the conditions alter the recommendations contained herein. The conclusions and recommendations presented in this report have been promulgated in accordance with generally accepted profession~ engineering practices in the field of geotechnical engineering. No other warranty is either expressed or implied. GILES ENGINEERING AS SOCIA TES, INC. I- I I I I I I I I I I I I I I I I I 1. 2. -3. 4. 5. 6. 7. 8. GUIDE SJ>ECIFICATIONS FOR SUBGRADE A_ND PREPARATION FOR FILL, FOUNDATION, FLOOR SLAB AND PAVEMENT SUPPORT; AND SELECTION, PLACEMENT AND COMPACTION OF FILL SOILS USING MODIFIED PROCTOR PROCEDURES Construction monitoring and testing of subgrades and grades for fill, foundation, floor slab and pavement; and fill selection, placement and compaction shall be performed by an experienced soils engineer and/or his representatives. All compacted fill, subgrades, and grades shall be (a) underlain by suitable bearing material, (b) free of all organic frozen, or other deleterious material, and (c) observed, tested and approved by qualified engineering personnel representing an experienced soils engineer. Preparation of subgrades after stripping vegetation, organic or other unsuitable materials shall consist of (a) proofrolling to detect soft, wet, yielding soils or other unstable materials that must be undercut, (b) scarifying top 6 to 8 inches, (c) moisture conditioning th~ soils as required, and (d) recompaction to same minimum in-situ density required for similar material indicated under Item 5. Note: Compaction requirements for pavement subgrade are higher than other areas. Weather and construction equipment may damage compacted fill surf ai;:e and reworking and retesting may be necessary for proper performance. In ovei"excavation and fill areas, the compacted fill must extend (a) a minimum I loot lateral distance beyond the exterior edge of the foWlda~ion at bearing grade or pavement at subgrade and down to compacted fill sub grade on a maximum 0.5(H): I (v) slope, (b) 1 foot above footing grade outside the building, and (c) to floor subgrade inside the building. Fill shall be placed and compacted on a 5(H): I (V) slope or must be stepped or benched as required to flatten if not specifically approved by qualified personnel under the direction of an experienced soils engineer. The compacted fill materials shall be free of deleterious, organic, or frozen matter, shall con lain no chemicals that may result in the materi~ being classified as "contaminated", and shall be low-ex-pansive with a maximum Liquid Limit (ASTM D-423) and Plasticity Index (AS1MD-424) of30 and 15, respectively, unless specifically tested and found to have low expansive properties and approved by an experienced soils eogineer. The top 12 inches of compacted fill should have a maximum 3 inch particle diameter and all underlying compacted fill a maximum 6 inch diameter: unless specifically approved by an experienced soils engineer. All fill material must be tested and approved under the direction ofan experienced soils engineer prior to placement. If the fill is to provide non-frost susceptible characteristics, it must be classified as a clean GW, GP, SW or SP per Unified Soils Classification System (ASTM D-2487). For structural fill depths less than 20 feet, the density of the structural compacted fill and scarified subgrade and grades shall not be less than 90 percent of the maximum dry density as determined by Modified Proctor (ASTM D-1557) with the exception of the top 12 inches of pavement sub grade which shall have a minimum in-situ density of 95 percent of maximum dry density, or 5 percent higher than Wlderlying structural fill maferials. Where the structural fill depth is greater than 20 feet, the portion below 20 feet should have a minimum in-place density of95 percent of i~ maximum dry density or 5 percent higher than the top 20 feet. Cohesive soils shall not vary by more than -1 to+ 3 pt,"fCl.'Ilt moisture content and granular soil ±3 percent from the optimum when placed and compacted or recompacted, unless specifically recommended/approved by the soils engineer observing the placement and compaction. Cohesive soils with moderate to high expansion potentials (PI> 15) should, however, be placed, compacted and maintained prior to construction at a 3±1 percent moisture content above optimum moisture content to limit future heave. Fill shall be placed in layers with a maximum loose thickness of 8 inches for foundations and IO inches for floor slabs and pavements, unless specifically approved by the soils engineer taking into consideration the type of materials and compaction equipment being used. The compaction equipment should consist of suitable mechanical equipment specifically designed for soil compaction. Bulldozers or similar tracked vehicles are typically not suitable for compaction. Excavation, filing, subgrade grade preparation shall be performed in a manner and sequence that will provide drainage at all times and proper control of erosion. Precipitation, springs, and seepage water encountered shall be pumped or drained to provide a suitable working platform. Springs or water seepage encountered during grade/foundation construction must be called to the soils engineer's attention immediately for possible construction procedure revision or inclusion of an underdrain system. Non-structural fill adjacent to structural Jill should typically be placed in unison to provide lateral support. Backfill along walls must be placed and compacted with care to ensure excessive unbalanced lateral pressures do not develop. The type of fill material placed adjacent to below grade walls (i.e. basement walls and retaining walls) must be properly tested and approved by an experienced soils engineer with consideration for the lateral pressure used in the wall design. Wherever, in the opinion of the soils engineer or the Ov.ner's Represt!nlatives, an unstable condition is being crc::ated either by cutting or filling, the work should not proceed into that area until an appropriate geotechnical exploration and analysis has been performed and th·e grading plan revised, iffound nece:,sary. . . GILES ENGINEERING ASSOCIATES, INC , ___ ---~A~RifH~s ~ft IAT1~l'!~ OF fflffliED ~fflt sYMlf.J c~!~~Es l'fU! s01~ f!fJNsTRUt;TION .,, ' Max.Dry Value as Value as Temporary Density Subgrade . Pavement Class Compaction Standard Compressibility Drainage and Value as an When Not Value as Base With Dust With •. Characteristics Proctor and Expansion Permeability Embankment Subject to Course Palliative Bituminous (pcl) Material Frost Treatment .·ow Good: tractor, rubber-tired; steel · 125-135 Almost none . Good drainage, Very stable Excellent Good Fair to Excellent wheel or \iibratory roller pervious Poor GP Good: tractor, rubber-tired., steel , 115-125 Almost none · Good drainage, Reasonably Excellent Poor to fair Poor wheel or vibratory roller . pervi<)us stable to good GM · Good: rubber-tired or light 120-135 . . Slight Poor drainage, , Reasonably Excellent Fair to poor Poor Poor to fair sheepsfoot roller semipervious stable to good GC Good to fair: rubber-tired or 115-130 Slight. Poor drainage, Reasonably Good Good to fair Excellent Excellent sheepsfoot roller . impervious stable ** SW Good: tractor, rubber-tired or 110-130 Almost none Good drainage, Very stable Good Fair to poor Fair to Good vibratory roller pervious. poor. SP Good: tractor, rubber-tired or 100-120 Almost none Good drainage, Reasonably Good to Poor Poor · Poor to fair vibratory roller · pervious stable when fair dense SM Good: rubber-tired or sheepsfoot 110-125 Slight Poor drainage, Reasonably . Good.to Poor PQor Poor to fair · roller impervious stable when fair dense SC Good to fair: rubber-tired or 105-125 Slight to Poor drainage, Reasonably Good to · Fair to poor Excellent Excellent sheepsfoot roller medium impervious . stable fair ML . Good to poor: rubber-tired or 95-12() Slight to Poor drainage, Poor stability, Fair to · Not suitable Poor Poor sheepsfoot r.oller medium impe,:vious high density poor required CL Good to fair: sheepsfoot or 95-120 Medium No drainage, · Good stability Fair to Not suitable Poor Poor rubber-tired roller impervious. poor OL Fair to poor: slieepsfoot or ·so-to'o Medium to high Poor drainage, Unstable, Poor Not suitable · Not Not suitable rubber-tired roller impervious should not be suitable us.ed MH Fair to poor: sheepsfoot or 70-95 High Poor drainage, . Poor stability, Poor Not suitable Very poor Not suitable rubber-tired roller · impervious should not be used CH Fair to poor: sheepsfoot roller 80-105 Very high No drainage, Fair stability, Poor to Not suitable Very poor Not suitable impervious may soften on very poor . expansion OH Fair to poor: sheepsfoot roller 65-100 High No drainage, Unstable, Very poor Not suitable Not Not suitable impervious should not be suitable used Pt Not suitable Very high Fair to poor Should not be Not Not suitable Not Not suitable drainage used suitable suitable * "The Unified Classification: Appendix A -Characteristics of Soil, Groups Pertaining to Roads and Airfields, and Appendix B-Characteristics of Soil Groups Pertaining to Embankments and Foundations," Technical Memorandum 357, U.S. Waterways lxperiment Station, Vicksburg, 1953. ** Not suitable if subject to frost. ~ GILES ENGINEERING ASSOCJATES1 INC. I ·I I I I I I I I I I I I ·I I I I I I GENERAL NOTES SAMPLE IDENTIFICATION All samples are visually classified in general accordance with the Unified Soil Classification System (ASTM D-2487-75 or D-2488-75) DESCRIPTIVE TERM(% BY DRY WEIGHT) PARTICLE SIZE (DIAMETER) Trace: 1-10% Boulders: 8 in and larger Little: 11-20% Cobbles: 3 in to 8 in - Some: 21-35% Gravel: coarse -¾ to 3 in And/Adjective 36-50% fme-No. 4 (4.76 mm) to¾ in Sand: Silt: Clay: coarse -No. 4 (4.76 mm) to No. IO (2.0 mm) medium-No. 10 (2.0·mm) to No. 40 (0.42 mm) fme -No. 40 (0.42 mm) to No. 200 (0.074 mm) No. 200 (0.074 mm) and smaller (Non-plastic) No. 200 (0.074 mm) and smaller (Plastic) SOIL PROPERTY-SYMBOLS DRILLING AND SAMPLING SYMBOLS Dd: LL: PL: PI: LOI: G~: K: w: -qp: qs: qu: qc: PID: N: Ne: Nr: Dry Density (pcf) Liquid Limit, percent Plastic Limit, percent Plasticity Index {LL-PL) Loss on Ignition, percent Specific Gravity Coefficient of Permeability Moistpre content, percent Calibrated Penetrometer Resistance, tsf Vane-Shear Strength, tsf Unconfmed Compressive Strength, tsf Static Cone Penetrometer Resistance SS: Split-Spoon ST: Shelby Tube-3" O.D. (except where noted) CS: 3" O.D. California long Sampler DC: Dynamic Cone Penetrometer per ASTM AU: DB: CB: WS: RB: BS: Note: Special Technical Publication No. 399 Auger Sam.pie Diamond Bit Carbide Bit Wash Sample Rock-Roller Bit Bulk Sample Depth intervals for sampling shown on Record of Subsurface :Exploration are not indicative of sample Correlated to Unconfmed Compressive Strength, tsf Results of vapor analysis conducted on represe~tative samples utilizing a Photoionization Detector cahbrated to a recovery, but position where sampling initiated be~ene standard. Results expressed in HNU-units (BDL=Below Detection Limits) Penetration :Resistance per 6 inch interval, or fraction thereof, for a standard 2 inch O.D. (1 % inch I.D.) split spoon sampler driven with a 140 pound weight free-falling 30 inches. Performed in general accordance with Standard Penetration Test Specifications (ASTM D-1586). N in blows per foot equals sum ofN values where plus sign is shown Penetration Resistance per 1 ¾ inches-of Dynamic Cone Pexietrometer. Approximately equivalent to Standard Penetration Test N-Value in blows per foot. Penetration Resistance per 6 jnch interval, or ft-action thereof, for California Ring Sampler driven with a 140 pound weight free- falling 30 inches per ASTM D-3550. Not equivalent to Standard Penetration Test N-V alue. SOIL STRENGTH CHARACTERISTICS COHESIVE (CLAYEY) SOILS NON-COHESIVE (GRANULAR) SOILS UNCONFINED COMPARATIVE BLOWS PER COMPRESSIVE ·coNSISTENCY FOOT(N) STRENGTH (TSF) Very Soft 0-2 0-0.25 Soft 3-4 0.25-0.50 Medium Stiff 5-8 0.50-1.00 Stiff 9-15 1.00-2.00 Very Stiff 16-30 2.00-4.00 Hard 31+ 4.oo+ DEGREE OF DEGREE OF PLASTICITY Pl EXPANSIVE POTENTIAL None to Slight 0-4 Low Slight 5-10 Medium Medium 11-30 High High to Very High 31+ GILES ENGINEERING ASSOCIATES, INC. RELATIVE DENSITY Very Loose Loose Finn Dense Very Dense Pl 0-15 15-25 25+ BLOWS PER FOOT(N) 0-4 5-10 11-30 31-50 51+