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Home My WebLink AboutCDP 02-45; Ocheltree Residence; PRELIMINARY GEOTECHNICAL INVESTIGATION; 2003-03-05Preliminary Geotechnical Investigation Proposed Single-Family Residence Hillside Drive, Carlsbad, California (A.P.N. #207 -022-1 0) March 5, 2003 Prepared For: MR. PAUL C. OCHELTREE 200 Marine View Avenue Del Mar, California 92014-3935 Prepared By: VINJE & MIDDLETON. ENGINEERING, INC. 2450 Vineyard Avenue, Suite 102 Escondido, California 92029 Job #03-145-P VINJE & MIDDLETON ENGINEERING, INC. Job #03-145-P March 5, 2003 Mr. Paul C. Ocheltree 200 Marine View Avenue Del Mar, California 92014-3935 2450Vineyard Avenue, #102 Escondido, California 92029-1229 Phone (760) 743-1214 Fax (760) 739-0343 PRELIMINARY GEOTECHNICAL INVESTIGATION, PROPOSED SINGLE-FAMILY RESIDENCE, HILLSIDE DRIVE, CARLSBAD, CALIFORNIA (A.P.N. #207-022-10) Pursuc;3nt to your request, Vinje and Middleton Engineering, Inc., has completed the Preliminary Geotechnical Investigation Report for the above-referenced project site. The following report summarizes the results of our field investigation, including laboratory analyzes and conclusions, and provides recommendations for the proposed residential development as understood. From a geotechnical engineering standpoint, it is our opinion that the site is suitable for the planned single-family residential development and associated improvements provided the recommendations presented in this report are incorporated into the design and construction of the project. The conclusions and recommendations provided in this study are consistent with the site geotechnical conditions and are intended to aid in preparation of final development plans and allow more accurate estimates of development costs. If you have any questions or need clarification, please do not hesitate to contact this office. Reference to our Job #03-145-P will help to expedite our response to your inquiries. We appreci<:;~te this opportunity to be of service to you. VINJE & MIDDLETON ENGINEERING, INC. crenniS Middleton · CEG #980 DM/jt TABLE OF CONTENTS PAGE NO. I. INTRODUCTION ......... ; . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . • 1 II. SITE DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Ill. PROPOSED DEVELOPMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 IV. SITE INVE.STIGATION ............................................. 2 V. GEOTECHNICAL CONDITIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 A. Earth Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 B. Surface and Subsurface Water . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 C. Slope Stability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 D. Faults I Seismicity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 E. Geologic Hazards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 F. Laboratory Testing I Results .............................. ~ . . . . . . 6 VI. CONCLUSIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 VII. RECOMMENDATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 A. Grading and Earthworks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 B. Foundations and Slab-on-Grades ................................ 13 C. Exterior Concrete Slabs I Flatworks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 D. Soil Design Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 E. Asphalt and PCC Pavement Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 F. General Recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 VIII. LIMITATIONS ................................................... 19 TABLE NO. Fault Zone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Site Seismic Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Soil Type ........................................................... 3 Maximum Dry Density and Optimum Moisture Content . . . . . . . . . . . . . . . . . . . . . 4 Moisture-Density Tests (Undisturbed Chunk Samples) ..................... 5 Expansion Index Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Direct Shear Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . • . 7 TABLE OF CONTENTS (continued) PLATE NO. Regional Index Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Site Plan ........................................................... 2 Test Trench Log (with key) ............................................ 3 Fault-Epicenter Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . • . . . . . . . . 4 Retaining Wall Drain Detail . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Isolation Joints and Re-entrant Corner Reinforcement . . . . . . . . . . . . . . . . . . . . . 6 PRELIMINARY GEOTECHNICAL INVESTIGATION PROPOSED SINGLE-FAMILY RESIDENCE HILLSIDE DRIVE, CARLSBAD, CALIFORNIA I. INTRODUCTION The property investigated for this work includes an undeveloped lot located off Hillside Drive within the City of Carlsbad. The property location is shown on a Regional Index Map enclosed with this report as Plate 1. We understand the subject property is planned for the support of a single-family residence and associated improvements. Therefore, this investigation was initiated to determine soils and rock conditions at the site and their impact upon the planned development. Test trench digging, geologic mapping, and soil I rock sampling and testing were among the activities condwcted in conjunction with this investigation that has resulted in the planning and development recommendations presented herein. II. SITE DESCRIPTION The study site is located on the east side of Hillside Drive within a residential section of the City of Carlsbad. Residential developments border the north and east sides ofthe site with an undeveloped lot to the south. The property is characterized by an approximate 12 feet deep ravine I flowline that traverses the central portion of the site and drains in a southwesterly direction. Natural slope gradients within the flowline approach 1:1 (horizontal to vertical) at their steepest. Elsewhere, site gradients approach 7:1. Up-slope to the north, the ravine has been filled as part of a previous residential development and a nearly 20 feet high 2:1 graded fill slope ascends to the developed properties above. A 24-inch storm drain and headwall, associated with the northern development outlets at the base of the northern fill slope. A variable height fill slope with 2:1 gradients is associated with the adjacent Hillside Drive along the westmargin. A Site Plan showing existing topographic conditions and the proposed development has been supplied by Ocheltree Architecture and is reproduced herein as Plate 2. Ill. PROPOSED DEVELOPMENT The study property is planned for the support of a residential dwelling and associated improvements. Project design schemes made available to us indicate that the proposed building will span over the flowline traversing the site in the middle sections. Retaining wails and end abutments are inGorporated into the design for building support. Continuous strip and spread pad concrete footings with slab-on-grade foundations are planned for building support on graded surfaces at either end of the dwelling. Steel beams which clear span from the end abutments constructed on either sides of the flowline will provide support for middle sections. VINJE & MIDDLETON ENGINEERING, INC. 2450 Vineyard Avenue, #102, Escondido, California 92029-1229 • Phone (760) 743-1214 • Fax (760) 739-0343 GEOTECHNICAL INVESTIGATIONS GRADING SUPERVISION PERC TESTING ENVIRONMENTAL INVESTIGATIONS PRELIMINARY GEOTECHNICAL INVESTIGATION HILLSIDE DRIVE, CARLSBAD, CALIFORNIA PAGE 2 MARCH 5, 2003 Grading within the flowline includes cutting back the existing side embankments to 2:1 gradients maximum and placement of erosion control rip-rap. IV. S~TE INVESTIGATION Subsurface conditions at the study property were primarily determined by geologic mapping of surface exposures and the excavation of one test trench dug with a tractor- mounted backhoe. The trench was entered and logged by our project geologist who also retained soil I rock samples for subsequent laboratory testing. The test trE3nch location is shown on Plate 2. A log of the Test Trench is enclosed as Plate 3. Laboratory test results are summarized in a following section. Trenching of the site was limited due to the existing steep-sided flowline. V. GEOTECHNICAL CONDITIONS The project site is largely natural terrain underlain by sedimentary formational units that are widely exposed in local coastal areas. Steep slopes associated with a ravine I flowline occur at the site. A. Earth Materials The project site is underlain by a section of Pleistocene age Terrace Deposits. Site Terrace Deposits typically consist of medium grained sandstone found in a poorly cemented and weathered friable condition near the surface becoming more cemented at depth. Natural alluvial soils occupy the lower canyon area in the central flowline area. Alluvial soil thickness is unknown, however, it is anticipated to be somewhat shallow. Project earth materials are sandy deposits with little or no expansion potential. B. Surface and Subsurface Water A detailed hydrology study has been completed by others for the project site. We understand that upstream drainage is controlled by a 48-inch storm sewer pipe, and the 24-inch drain is an overflow drain installed at the toe of the northern slope as a precaution. Outflow from the 24-inch drain is expected to be negligible, and down stream flooding or lower ground inundation is not anticipated. We further understand that erosion or scouring of flowline bed and side embankments as a result of storm flow conditions is not considered likely. VINJE & MIDDLETON ENGINEERING, INC. 2450 Vineyard Avenue, #102, Escondido, California 92029·1229 • Phone (760) 743·1214 • Fax (760) 739-0343 GEOTECHNICAL INVESTIGATIONS GRADING ~UPERVISION PERC TESTING ENVIRONMENTAL INVESTIGATIONS PRELIMINARY GEOTECHNICAL INVESTIGATION HILLSIDE DRIVE, CARLSBAD, CALIFORNIA PAGE 3 MARCH 5, 2003 Groundwater conditions were not encountered in our exploratory trench excavation to the depths explored. Natural groundwater is not expected to impact the project construction or future stability of the developed site. C. Slope Stability Moderate slopes are present at the site and on the adjacent property to the north. Project existing slopes consist of natural slopes associated with the site flowline. Flowline slopes are approximately 12 vertical feet in height with slope gradients approaching 1:1 (horizontal to vertical) at their steepest. Nearby slopes consist primarily of graded fill slopes associated with adjacent developments. The fill slopes are approximately 20 vertical feet in height with 2:1 slope gradients. · Instability is not indicated within project or nearby slopes. D. Faults l Seismicity Faults or significant shear zones are not indicated on or near proximity to the project site. As with most areas of California, the San Diego region lies within a seismically active zone; however, coastal areas of the county are characterized by low levels of seismic activity relative. to inland areas to the east. During a 40-year period (1934-1974), 37 earthquakes were recorded in San Diego coastal areas by the California Institute of Technology. None of the recorded events exceeded a Richter magnitude of 3.7, nor did any of the earthquakes generate more than modest ground shaking or significant damages. Most of the recorded events occurred along various offshore faults which characteristically generate modest earthquakes. · Historically, the most significant earthquake events which affect local areas originate along well known, distant fault zones to tfie east and the Coronado Bank Fault to the west. Based upon available seismic. data, compiled from California Earthquake Catalogs, the most significant historical event in the area of the study site occurred in 1800 at an estimated distance of 11 miles from the project area. This event, which is thought to have occurred along an off-shore fault, reached an estimated magnitude of 6.5 with estimated bedrock acceleration values of 0.095g at the project site. The following list represents the most significant faults which. VINJE & MIDDLETON ENGINEERING, INC. 2450 Vineyard Avenue, #102, Escondido, California 92029-1229 • Phone (760) 743-1214 • Fax (760) 739-0343 GEOTECHNICAL INVESTIGATIONS GRADING SUPERVISION PERC TESTING ENVIRONMENTAL INVESTIGATIONS PRELIMINARY GEOTECHNICAL INVESTIGATION HILLS.IDE DRIVE, CARLSBAD, CALIFORNIA PAGE 4 MARCH 5, 2003 commonly impact the region. Estimated ground acceleration data compiled from Digitized California Faults (Computer Program EQ FAULT VERSION 3.00 updated) typically associated with the fault is al.so tabulated: TABLE 1 Rose .Canyon fault 5 miles 0.184 9 Newport-Inglewood fault 6 miles 0.170 9 Coronado Bank fault 21 miles 0.140 9 Elsinore fault 24 miles 0.109 The locationJ of significant faults and earthquake events relative to the study site are depicted on a Fault-Epicenter Map enclosed with this report as Plate 4. More recently, the number of seismic events which affect the region appears to have heightened somewhat. Nearly 40 earthquakes of magnitude 3.5 or higher have been recorded in coastal regions between January 1984 and August 19a6. Most of the earthquakes are thought to have been generated along offshore faults. For the most part, the recorded events remain moderate shocks which typically resulted in low levels of ground shaking to local areas. A notable exception to this pattern was recorded on July 13, 1986. An earthquake of magnitude 5.3 shook County coastal areas with moderate to locally heavy ground shaking resulting in $700,000 in damages, one death, and injuries to 30 people. The quake occurred along an offshore fault located nearly 30 miles southwest of Oceanside. A series of notable events shook County areas with a (maximum) magnitude 7.4 shock in the early morning of June 28, 1992. These quakes originated along related segments of the San Andreas Fault approximately 90 miles to the north. Locally. high levels of ground shaking over an extended period of time resulted; however, significant damages to local structures were not reported. The increase in earthquake frequency in the region remains a subject of speculation among . geologists; however, based upon empirical information and the recorded seismic history of County areas, the 1986 and 1992 eveQts are thought to represent the highest levels of ground shaking which can be expected at the study site as a result of seismic activity. VINJE & MIDDLETON ENGINEERING, INC. 2450 Vineyard Avenue, #102, Escondido, California 92029-1229 • Phone (760) 743-1214 • Fax (760) 739-0343 GEOTECHNICAL INVESTIGATIONS GRADING SUPERVISION PE~C TESTING ENVIRONMENTAL INVESTIGATIONS PRELIMINARY GEOTECHNICAL INVESTIGATION HILLSIDE DRIVE, CARLSBAD~ CALIFORNIA PAGE 5 MARCH 5, 2003 In recent years, the Rose Canyon Fault has received added attention from geologists. The fault is a significant structural feature in metropolitan San Diego which includes a series of parallel breaks trending southward from La Jolla Cove through San Diego Bay toward the Mexican border. Test trenching along the fault in Rose Canyon indicated that at that location the fault was last active 6,000 to 9,000 years ago. More rec~nt work suggests that segments of the fault are younger having been last active 1000 -2000 years ago. Consequently, the fault has been classified as active and included within an Alquist-Priolo Special Studies Zone established by the State of California. Fault zones tabulated in the preceding table are considered most likely to impact the region of the study site during the lifetime of the project. The faults are periodically active and capable of generating moderate to locally high levels of ground shaking at the site. Ground separation as a result of seismic activity is not expected at the property. For design purposes, specific site seismic parameters were determined as part of this investigation in accordance with the Uniform Building Code. The following parameters are consistent with the indicated project seismic environment and may be utilized for project design work: TABLE 2 Division IV of the 1997 Uniform Buildi Code. E. Geologic Hazards Geologic hazards are not presently indicated at the project site. Moderate exposed natural slopes do not indicate gross geologic instability. Nearby graded fill slopes are performing well. The most significant geologic hazards at the property will be those associated with ground shaking in the event of a major seismic event. Liquefaction or related ground rupture failures are not anticipated. VINJE & MIDDLETON ENGINEERING, INC. 2450 Vineyard Avenue, #102, Escondido, California 92029·1229 • Phone (760) 743·1214 • Fax (760) 739·0343 GEOTECHNICAL INVESTIGATIONS GRADING SUPERVISION PERC TESTING ENVIRONMENTAL INVESTIGATIONS PRELIMINARY GEOTECHNICAL INVESTIGATION HIL_LSIDE DRIVE, CARLSBAD, CALIFORNIA F. Laboratory Testing I Results PAGE 6 MARCH 5, 2003 Earth deposits encountered in our exploratory test excavations were closely examined and sampled for laboratory testing. Based upon our test trench data and field exposures, site soils have been grouped into the following soil types: TABLE 3 The following tests were conducted in support of this investigation: 1. Maximum Dry Density and Optimum Moisture Content: The maximum dry density and optimum moisture content of Soil Type 1 was determined in accordance with ASTM D-1557. The test result is presented in Table 4. TABLE 4 T-1 2' 1 117.2 12.5 2. Moisture-Density Tests (Undisturbed Chunk Samples): In-place dry density and moisture content of representative soil deposits beneath the site were determined from relatively undisturbed chunk samples using the water . displacement test method. The test results are presented in Table 5 and tabulated on the enclosed Test Trench Log, Plate 3. TABLE 5 T-1 @ 1' 1 2.9 98.1 117.2 83.7 T-1@ 2' 1 3.4 97.9 117.2 83.6 T-1 @ 4' 2.5 97.6 117.2 83.3 VINJE & MIDDLETON ENGINEERING, INC. 2450 Vineyard Avenue, #102, Escondido, California 92029-1229 • Phone (760) 743-1214 • Fax (760) 739-0343 GEOTECHNICAL INVESTIGATIONS GRADING SUPERVISION PERC TESTIN.G ENVIRONMENTAL INVESTIGATIONS PRELIMINARY GEOTECHNICAL INVESTIGATION HILLSIDE DRIVE, CARLSBAD, CALIFORNIA TABLE 5 (continued) T-1@ 5' 1 1.8 95.5 117.2 T-1@ 6' 1 3.9 105.9 117.2 * Designated as re.lative compaction for structural fills. PAGE 7 MARCH 5, 2003 81.5 90.4 Required relative compaction for structural fill is 90% or greater. 3. Expansion Index Test: One expansion index test was performed on a representative sample of Soil Type 1 in accordance with the Uniform Building Code Standard 18-2. The testresult is presented in Table 6. TABLE 6 T-1@ 2' 1 non-expansive ( w) = moisture content in percent. 4. Direct Shear Test: One direct shear test was performed on a representative sample' of Soil Type 1. The prepared specimen was soaked overnight, loaded with normal loads of 1, 2, and 4 kips per square foot respectively, and sheared to failure in an undrained condition. The test result is presented in Table 7. TABLE 7 VI. CONCLUSIONS Based upon the foregoing investigation, development of the study site for residential purposes is feasible from a geotechnical viewpoint. The property is underlain by dense, stable Terrace Deposits. Instability is not indicated at the site. VINJE & MIDDLETON ENGINEERING, INC. 2450 Vineyard Avenue, #102, Escondido, California 92029-1229 • Phone (760) 743-1214 • Fax (760) 739-0343 GEOTECHNICAL INVESTIGATIONS GRADING SUPERVISION PERC TESTING ENVIRONMENTAL INVESTIGATIONS PRELIMINARY GEOTECHNICAL INVESTIGATION HILLSIDE DRIVE, CARLSBAD, CALIFORNIA PAGE 8 MARCH 5, 2003 The following factors are unique to the property and will most impact its development from a geotechnical viewpoint: * * * * * No evidence of flooding or excessive run-off erosion is apparent within project canyon terrain. However, the project civil engineer should verify acceptable conditions within the canyon with regard to anticipated stream levels. Underlying Terrace Deposit soils at the property are dense, stable units which will adequately support the planned dwelling. Some removal and recompaction of upper, more weathered Terrace. Deposit soils is recommended in the following section in order to create uniform bearing surfaces and stable ground for the support of the planned dwelling. Project earth materials are granular, non-expansive sands which work well in compacted fill and backfills. Unusual grading problems, including hard rock excavations are not expected. Based upon the project,grading scheme and recommendations provided herein, on-site bearing soils are anticipated to consist of medium grained sands (SP) with very low expansion potential (EIIess than 21), according to the Uniform Building Code classification. Expansive soils will not be a factor in the pevelopment of the project property. Natural groundwater is not expected to impact project grading or the long term stability of the developed site. * Adequate site surface drainage control is a critical factor in the future stability of the developed property as planned. Drainage control facilities should be designed and installed for proper control and disposal of surface run-off. * Liquefaction and seismically induced settlements will not be a factor in the development of the proposed structures and improvements. * Post construction settlements are not expected to be a factor in the development of the project site, provided our site remedial grading and foundation recommendations are implemented durihg the construction phase of the project. * Soil collapse will not be a factor in development of the study site, provided our recommendations for site development are followed. VINJE & MIDDLETON ENGINEERING, INC. 2450 Vineyard Avenue, #102, Escondido, California 92029-1229 • Phone (760) 743-1214 • Fax (760) 739-0343 GEOTECHNICAL INVESTIGATIONS GRADING SUPERVISION PERC TESTING ENVIRONMENTAL INVESTIGATIONS PRELIMINARY GEOTECHNICAL INVESTIGATION HILLSIDE DRIVE, CARLSBAD, CALIFORNIA VII. RECOMMENDATIONS PAGE 9 MARCH 5, 2003 The f9llowing recommendations are consistent with the indicated geotechnical conditions at the project site and should be reflected in final plans and implemented during the construction phase. Added or modified recommendations may also be appropriate and can be provided at the final plan review phase when building and foundation plans are available: A. Grading and Earthworks All grading and project construction should be completed in accordance with Appendix Chapter 33 of the Uniform Building Code, City of Carlsbad Grading Ordinances, the Standard Specifications for Public Works Construction, and the requirements of the following sections wherever applicable: 1. Clearing and Grubbing -Surface vegetation, deleterious materials and debris should be removed from all areas of planned new fills I backfills, structures and improvements plus 10 feet. The prepared ground should be inspected and approved by the project geotechnical engineer or his designated field representative prior to grading. 2. Earthworks and Remedial Grading -The project upper terrain are directly underlain by natural sandstone Terrace Deposits which occur in a medium d~nse condition near the surface becoming more dense with depth. Proposed development include retaining walls and end abutments to construct level building surfaces on either sides of the existing flowline. The planned building will also have a clear span from end abutments, and middle span supports within the lower flowline terrain underlain by alluvial deposits are not planned. Project earthwork operations will primarily consistof cut grading of the flowline embankments to flatter 2:1 gradients and backfilling behind the upper retaining walls and end abutments. In all areas to receive new fills, backfills, structures and improvements plus 10 feet, the upper weathered Terrace Deposits should be over-excavated to a minimum depth of 3 feet and placed back as properly compacted fills. · There should be at least 12 inches of compacted fills underneath all foundations. In the case of deeper retaining walls or abutment footings, the bottom of the foundation trenches should be over-excavated a minimum or 12 inches and reconstructed to bottom of foundation elevations with compacted fills placed as specified herein. VINJE & MIDDLETON ENGINEERING, INC. 2450 Vineyard Avenue, #102, Escondido, Ccdifomia 92029-1229 • Phone (760) 743-1214 • Fax (760) 739-0343 GEOTECHNICAL INVESTIGATIONS GRADING SUPERVISION PERC: TESTING ENVIRONMENTAL INVESTIGATIONS PRELIMINARY GEOTECHNICAL INVESTIGATION HILLSIDE DRIVE, CARLSBAD, CALIFORNIA PAGE 10 MARCH 5, 2003 Bottom of all over-excavations should also be ripped-and-recompacted in-place to a minimum depth of 12 inches. Ground receiving new fills or backfills should also be. properly benched and keyed as directed in.field. 3. Bearing I subgrade soils -Building foundations. and footings for site structures should be uniformly supported on compacted fills. Dissimilar bearing and subgrade soils should not be permitted underneath the proposed structures and improvements. In the roadways, driveway and parking improvement dissimilar subgrade soils, there should be a minimum 12 inches of uniformly compacted fills below rough finish subgrade. 4. Fill I Backfill Materials and Compaction -Soils generated from the excavations of project Terrace Deposits will predominantly generate good quality sands which will perform well as project compacted fills and backfills. Uniform bearing soil conditions should be constructed at the site by the remedial grading and backfill operations. Site fills and backfills should be adequately processed, thoroughly mixed, .moisture conditioned to slightly (2%) above optimum moisture levels as directed in the field, placed in thin uniform horizontal lifts and mechanically compacted to a minimum of 95% of the corresponding laboratory maximum dry density per the ASTM D-1557, unless otherwise specified. · Import soils, if required to complete grading and achieve design grades, should be sandy granular non-expansive deposits, inspected, tested as necessary and approved by the project geotechnical consultant prior to the delivery to the site. 5. Permanent Graded Slopes -Project development, as proposed, will not create new graded fill slopes. Portions of the existing over-steepened flowline embankment, however, will be graded to flatter 2:1 gradients. Regraded cut slopes constructed at the proposed heights and gradients will be grossly stable with respect to deep seated and surficial failures for the indicated design maximum vertical heights. Graded cut slopes developed at the site should be inspected and approved by the project geotechnical consultant during the grading to confirm stability. Additional recommendations including the need for track-walking the slope face should be provided at that time based on the conditions of Terrace Deposits exposed at the finish surfaces. VINJE & MIDDLETON ENGINEERING, INC. 2450 Vineyard Avenue, #102, Escondido, California 92029-1229 • Phone (760) 743-1214 • Fax (760) 739-0343 GEOTECHNICAL INYESTIGATIONS GRADING SUPERVISION PERC TESTING ENVIRONMENTAL INVESTIGATIONS PRELIMINARY GEOTECHNICAL INVESTIGATION HILLSIDE DRIVE, CARLSBAD, CALIFORNIA PAGE 11 MARCH 5, 2003 6. Wall Back Drainage System -Subsurface back drainage system consisting of a minimum 4-inch diameter, Schedule 40 (SDR 35) perforated pipe surrounded in a minimum of 3. cubic feet per foot of %-inch crushed rocks wrapped in filter fabric (Mirafi 140 N or equivalent), or Caltrans Class 2 permeable aggregate, should be provided behind all planned end abutments and site retaining I basement walls in general accordance with the enclosed Plate 5. Filter fabric can be eliminated if Caltrans Class 2 permeable material is used. The invert of the subdrainage pipe should be established at suitable elevations to ensure positive drainage into an approved drainage facility via a 4-inch solid tight line pipe. Protect pipe outlets as appropriate. Provide wall water proofing as specified on the approved plans. 7. Drainage and Erosion Control-A critical element to the continued stability of the graded building pads and slopes is an adequate surface drainage system and protection of the slope face. This can most effectively be achieved by appropriate Vegetation cover and the installation of the following systems: * Over-flow of pad surface water over the top of slopes or concentrated flow over the slope face should not be allowed. Drainage swales should be provided at the top and toe of the graded slopes per the project civil engineer design. * Erosion or scouring of the flowline bed or side embankment ~hould not be allowed. Flood and storm water control facilities should be installed per the approved civil drawings. * Building pad surface run-off should be collected and directed away from the planned buildings and improvements to a selected location in a controlled manner. Area drains should be installed. * The finished slope should be planted soon after completion of grading. Unprotected slope faces will be subject to severe erbsion and should not be allowed. Over-watering of the slope faces should also not be allowed. Only the amount of water to sustain vegetation should be provided. * Temporary erosion control facilities and silt fences should be installed during the construction phase periods and until landscaping is established as indicated and specified on the approved project grading I erosion control plans. VINJE & MIDDLETON ENGINEERING, INC. 2450 Vin~yard Avenue, #102, Escondido, California 92029-1229 • Phone (760) 743·1214 • Fax (760) 739-0343 GEOTECHNICAL INVESTIGATIONS GRADING SUPERVISION PERC TESTING ENVIRONMENTAL INVESTIGATIONS PRELIMINARY GEOTECHNICAL INVESTIGATION HILLSIDE DRIVE, CARLSBAD, CALIFORNIA PAGE 12 MARCH 5, 2003 8. Engineering Inspections -All grading operations including removals, suitability of earth deposits used as compacted fill I backfill, and compaction procedures should be continuously inspected and tested by th.e project geotechnical consultant and presented in the final as-graded compaction report. The nature of finished grade soils should also be confirmed in the final compaction report at the completion of grading. Geotechnical engineering inspections shall include, but not limited to the following: * Initial Inspection-After the grading I brushing limits have been staked, but before grading I brushing starts. * Bottom of over-excavation inspection -After the natural ground or bedrock is exposed and prepared to receive fill, but before fill is placed. * . Cut slope I excavation inspection -After the excavation is started, but before the vertical depth of excavation is more than 5 feet. Local and CAL-OSHA safety requirements for open excavations apply. * Fill I wall backfill inspection-After the fill I wall backfill placement is started, but before the vertical height of fill I backfill exceeds 2 feet. A minimum of one test shall be required for each 100 lineal feet maximum with the exception of wall backfillswhere a minimum of one test shall be required for each 25 lineal feet maximum. Wall backfills shall also be mechanically compacted to a minimum of 95% compaction levels unless otherwise specified. Finish rough and final pad grade tests shall be required regardless of fill thickness. * Foundation trench inspection -After the foundation trench excavations, but before steel placement. * Foundation bearing I slab subgrade soils inspection -Within 72 hours prior to the placement of concrete for proper moisture and specified compaction levels. * Geotechnical foundation I slab steel inspection -After the steel placement is completed, but 24 hours before the scheduled concrete pour. * Subdrain I wall back drain inspection -After the trench excavations, but during the actual placement. All material shall conform to the project material specifications and approved by the project geotechnical engineer. VINJE & MIDDLE'I:ON ENGINEERING, INC. 2450 Vineyard Ayenue, #102, Escondido, California 92029-1229 • Phone (760) 743-1214 • Fax (760) 739-0343 GEOTECHNICAL INVESTIGATIONS GRADING SUPERVISCON PERC TESTING ENVIRONMENTAL INVESTIGATIONS PRELIMINARY GEOTECHNICAL INVESTIGATION HILLSIDE DRIVE, CARLSBAD, CALIFORNIA PAGE 13 MARCH 5, 2003 * Underground utility I plumbing trench inspection -After the trench excavations, but before installation of the underground facilities. Local and CAL-OSHA safety requirements for open excavations apply. Inspection at the bottom of the trench and pipe bedding may also be required by the project geotechnical engineer. * Underground utility I plumbing trench backfill inspection -After the backfill placement is started above the pipe zone, but before the vertical height of backfill exceeds 2 feet. Testing of the backfill within the pipe zorie may also be required by the governing agencies. Pipe bedding and backfill materials shall· conform to the governing agencies requirements and project soils report if applicable. All trench backfills shall be mechanically compacted to a minimum of 95% compaction levels unless otherwise specified. Plumbing trenches over 12 inches deep maximum under the interior floor slabs should be mechanically compacted and tested for a minimum of 95% compaction levels. Flooding orjetting techniques as a means of compaction method shall not be allowed. * Pavement I improvements subgrade and basegrade inspections -Within 72 hours. prior to the placement of concrete or asphalt for proper moisture and specified compaction levels. · B. Foundations and Slab-on-Grades The following preliminary recommendations are consistent with very low expansive (EIIess than 21) sandy (SP) foundation bearing soil and site specific geotechnical conditions. Additional recommendations may be required and should be given at the plan review phase. All design recommendations should also be further confirmed and I or revised at the completion of rough grading based on the expansion characteristics of the foundation bearing soils and as-graded site geotechnical conditions, and presented in the final as-graded compaction report: 1. Continuous wall foundations should be sized at least 15 inches wide and 18 inches deep for single-story and two-story structures.. Spread pad footings should be at least 24 inches square and 12 inches deep. Footing depths are measured from the lowest adjacent ground surface, not including the sand I gravel layer beneath floor slabs. Exterior continuous footings should enclose the entire building perimeter. 2. Continuous interior and exterior foundations should be reinforced with a minimum of 4-#4 reinforcing bars. Place 2.,.#4 bars 3 inches above the bottom of the footing and 2-#4 bars 3 inches below the top of the footing. VINJE & MIDDLETON ENGINEERING, INC. 2450 Vineyard Avenue, #102, Escondido, California 92029·1229 • Phone (760) 743-1214 • Fax (760) 739-0343 GEOTECHNICAL INVESTIGATIONS GRADING SUPERVISION PERC TESTING ENVIRONMENTAL INVESTIGATIONS PRELIMINARY GEOTECHNICAL INVESTIGATION HILLSIDE DRIVE, CARLSBAD, CALIFORNIA PAGE 14 MARCH 5, 2003 Reinforcement details for isolated ·pad footings should be provided by the project architect I structural engineer. 3. All interior slab-on-grade floors should be a minimum of 4 inches in thickness, reinforced with #3 reinforcing bars spaced 16 inches on center each way, placed mid-height in the slab. Slabs should be underlain by 4 inches of clean sand (SE 30 or greater) which is provided with a 6-mil plastic moisture barrier placed mid-height in the sand. In the case of good quality sandy subgrade soils, as approved by the project geotechnical engineer, the 6-mil plastic moisture barrier may be laid directly over the slab subgrade and covered with a minimum of 2 inches of clean sand (SE .30 or greater). 4. Provide "softcut" contraction I control joints consisting of sawcuts spaced 10 feet on center maximum each way for interior slab-on-grade floors. Cut as soon as the slab will support the weight of the saw, and operate without disturbing the final finish which is normally within 2 hours after final finish at each control joint location or 150 psi to 800 psi. The softcuts should be a minimum of 1-inch in depth but not to exceed 1 %-inches. Anti-ravel.skid plates should be used and replaced with each blade to avoid spalling and raveling. Avoid wheeled equipment across cuts for at least 24 hours. 5. Provide re-entrant corner reinforcement for all interior slabs. Re-entrant corners will depend on slab geometry and I or interior column locations. The enclosed Plate 6 may be used as a general guideline. 6. All foundations I slabs should be uniformly supported on certified minimum 95% compacted fills as recommended herein. Foundation trenches and slab subgrade soils should be inspected and tested for proper moisture and specified compaction levels and approved by the project geotechnical consultant within 72 hours prior to the placement of concrete. 7. Footings located on or adjacent to the top of slopes should be extended to a sufficient depth to provide a minimum horizontal distance of 7 feet or one-third of the slope height, whichever is greater (need not exceed 40 feet maximum) between the bottom outside edge of the footing and face of slope. This requirement applies to all improvements, and structures including end abutments, retaining walls, fences, posts, pools, spas, etc. Concrete and AC improvements should be provided with a thickened edge to satisfy this requirement. VINJE & MIDDLETON ENGINEERING, INC. 2450 Vineyard Avenue, #102, Escondido, California 92029-1229 • Phone (760) 743·1214 • Fax (760) 739-0343 GEOTECHNICAL INVESTIGATIONS GRADING SUPERVISION PERC TESTING ENVIRONMENTAL INVESTIGATIONS PRELIMINARY GEOTECHNICAL INVESTIGATION HILLSIDE DRIVE, CARLSBAD, CALIFORNIA C. Exterior Concrete Slabs I Flatworks PAGE 15 MARCH 5, 2003 1. All exterior slabs (walkways, and patios) should be a minimum of 4 inches in thickness, reinforced with 6x6/1 Ox1 0 welded wire mesh carefully placed mid- height in the slab; 2. Provide "tool joint" or ''softcut" contraction I control joints spaced 10 feet on center (not to exceed 12 feet maximum) each way. Tool or cut as soon as the slab will support weight and can be operated without disturbing the final finish which is normally within 2 hours after final finish at each control joint location or 150 psi to 800 psi. Tool or softcuts should be a minimum of 1-inch but should not exceed 1 %-inches deep maximum. In case of softcut joints, anti- ravel skid plates should be used and replaced with each blade to avoid spalling and raveling. Avoid wheeled equipments across cuts for at least 24 hours. 3. Subgrade soils should be tested for proper moisture and specified compaction levels and approved by the project geotechnical consultant within 72 hours prior to the placement of concrete. · D. Soil Design Parameters The following soil design parameters are based upon tested representative samples of on-site earth deposits. All parameters should be re-evaluated when the characteristics of the final as-graded soils have been specifically determined: * · Design wet density of soil = 118.0 pcf. * Design angle of internal friction of soil = 30 degrees. * Design active soil pressure for retaining structures = 39 pcf (EFP), level backfill, cantilever, unrestrained walls. * Design at-rest soil pressure for retaining structures = 59 pcf (EFP), non- yielding, restrained walls. * Design passive soil pressure for retaining structures = 354 pcf (EFP), level surface at the toe. * Design passive soil pressure for retaining structures = 136 pcf (EFP), 2:1 sloping down surface at the toe. * Design coefficient of friction for concrete on soils= 0.36. * Net allowable foundation pressure for 95% compacted fill (minimum 15 inches wide by 18 inches deep footings) = 2000 psf. * Allowai:)le lateral bearing pressure (all structures except retaining walls) for certified on-site soils = 150 psflft . VINJE & MIDDLETON ENGINEERING, INC. 2450 Vineyard Avenue, #102, Escondido, California 92029·1229 • Phone (760) 743·1214 • Fax (760) 739-0343 GEOTECHNICAL INVESTIGATIONS GRADING SUPERVISION PERC TESTING ENVIRONMENTAL INVESTIGATIONS PRELIMINARY GEOTECHNICAL INVESTIGATION HILLSIDE DRIVE, CARLSBAD, CALIFORNIA PAGE 16 MARCH 5, 2003 Notes- * * * * Use a minimum safety factor of 1.5 for wall over-turning and sliding stability. However, because large movements must take place before maximum passive resistance can be developed, a minimum safety factor of 2 may be considered for sliding stability particularly where sensitive structures and improvements are planned nearer on top of retaining walls I abutments. When combining passive pressure and frictional resistance, the passive component should be reduced by one-third. The indicated net allowable foundation pressures provided herein were determined based on a minimum of 15 inches wide by 18 inches deep footings and may be increased by .20% for each additional foot of depth and 20% for each additional foot of width to a maximum of 4000 psf. The allowable foundation pressures provided herein also apply to dead plus live loads and may be increased by one-third for wind and seismic loading. The lateral bearing earth pressures may be increased by the amount of designated value for each additional foot of depth to a maximum of 1500 pounds per square foot. E. Asphalt and PCC Pavement Design Specific pavement section can best be provided at the completion of rough grading based on R-value tests of the actual finish subgrade soils and design Tl. The minimum structural section required by the respective agencies may also govern the design. The following structural sections may be considered for cost estimating purposes only (not for construction): 1. A minimum section of 3 inches asphalt on 6 inches Caltrans Class 2 aggregate base may be considered for on-site asphalt paving surfaces. Base materials should be compacted to a minimum of 95% of the corresponding maximum dry density (ASTM D-1557). Subgrade soils beneath the asphalt paving surfaces should be compacted to a minimum of 95% of the corresponding maximum dry density within the upper 12 inches. 2. Residential PCC driveways and parking supported on very low expansive (EI less than 21) subgrade soils should be a minimum of 5% inches in thickness, reinforced with #3 reinforcing bars at 18 inches on centers each way, placed 2 VINJE & MIDDLETON ENGINEERING, INC. 2450 Vineyard Avenue, #102, Escondido, California 92029-1229 • Phone (760) 743-1214 • Fax (760) 739-0343 GEOTECHNICAL INVESTIGATIONS GRADING SUPERVISION PERC TESTING ENVIRONMENTAL INVESTIGATIONS PRELIMINARY GEOTECHNICAL INVESTIGATION HILLSIDE DRIVE, CARLSBAD, CALIFORNIA PAGE 17 MARCH 5, 2003 inches below the top of slab. Subgrade soils beneath the PCC driveways and parking should also be compacted to a minimum of 95% of the corresponding maximum dry density in the upper 6 inches unless otherwise approved. Provide "tool joint" or "softcut" contraction I control joints spaced .1 0 feet on center (not to exceed 15 feet maximum) each way. Tool or cut as soon as the slab will support weight and can be operated without disturbing the final finish which is normally within 2 hours after final finish at each control joint location or 150 psi to 800 psi. Tool or softcuts should be a minimum of 1-inch but should not exceed 1 %-inches deep maximum. In case of softcut joints, anti- ravel skid plates should be used and replaced with each blade to avoid spalling and raveling. Avoid wheeled equipments across cuts for at least 24 hours. · 3. Subgrade and basegrade soils should be tested for proper moisture and the specified compaction levels, and approved by the project geotechnical consultant within 72 hours prior to the placement of the base or asphalt I PCC finish surface. 4. Base section and subgrade preparations per structural section design, will be required for all surfaces subject to traffic including roadways, travelways, drive lanes, driveway approaches and ribbon (cross) gutters. Driveway approaches within the public right-of-way should have 12 inches subgrade compacted to a minimum of 95% compaction levels, and provided with a 95% compacted Class 2 base section per the structural section design. · Base. layer under curb and gutters should be compacted to a minimum of 95%, while subgrade soils under curb and gutters, and base and subgrade under sidewalks may be compacted to a minimum of 90% compaction levels. Appropriate recommendations should be given in the final as-graded compaction report. F. General Recommendations 1. The minimum foundation design and steel reinforcement provided herein is based upon soil characteristics only and is not intended to be in lieu of reinforcement necessary for structural considerations. All recommendations should be evaluated and confirmed by the project architect I structural engineer. 2. Adequate staking and grading control is a critical factor in properly completing the recommended remedial and site grading operations. Grading control and. VINJE & MIDDLETON ENGINEERING, INC. 2450 Vineyard Avenue, #102, Escondido, California 92029·1229 • Phone (760) 743·1214 • Fax (760) 739-0343 GEOTECHNICAL INVESTIGATIONS GRADING SUPERVISION PERC TESTING ENVIRONMENTAL INVESTIGATIONS PRELIMINARY GEOTECHNICAL INVESTIGATION HILLSIDE DRIVE, CARLSBAD, CALIFORNIA PAGE 18 MARCH 5, 2003 staking should be provided by the project grading contractor or surveyor I civil engineer, and is beyond the geotechnical engineering services. Inadequate staking and I or lack of grading control may result in unnecessary additional grading which will increase construction costs. 3. Potentially expansive soils should not be used for backfilling of any retaining structure. All retaining walls should be provided with a 1:1 wedge of granular, compacted backfill measured from the base of the. wall footing to the finish surface. Retaining walls should be provided with a back drainage in general accordance with the enclosed Plate 5. 4. All underground utility and plumbing trenches should be mechanically compacted to a minimum 95% of the maximum dry density of the soil unless otherwise specified. Care should be taken not to crush the utilities or pipes during the compaction of the soil. Non-expansive, granular backfill soils should be used. 5. Site drainage over the finish pad surface should flow away from structures onto the street in a positive manner. Care should be taken during the construction, improvements, and fine grading phases not to disrupt the designed drainage patterns. Rooflines of the buildings should be provided with roof gutters, Roof water should be collected and directed away from the buildings and structures · to a suitable location. Consideration should be given to adequately damp-proof I waterproof the basement walls I foundations, and provide the planter areas adjacent to the foundations with an impermeable liner and a subdrainage system. 6. Final plans should reflect preliminary recommendations given in this report. Final foundations and grading plans may also be reviewed by the project geotechnical consultant for conformance with the requirements of the geotechnical investigation report outlined herein. More specific recommendations may be necessary and should be given when final grading and architectural I structural drawings are available. 7. All foundation trenches should be inspected to ensure adequate footing embedment and confirm competent bearing soils. Foundation and slab reinforcements should also be inspected and approved by the project geotechnical consultant. VINJE & MIDDLETON ENGINEERING, INC. 2450 Vineyard Avenue, #102, Escondido, California 92029-1229 • Phone (760) 743·1214 • Fax (760) 739·0343 GEOTECHNICAL INVESTIGATIONS GRADING SUPERVISION PERC TESTING ENVIRONMENTAL INVESTIGATIONS PRELIMINARY GEOTECHNICAL INVESTIGATION HILLSIDE DRIVE, CARLSBAD, CALIFORNIA PAGE 19 MARCH 5, 2003 8. The amount of shrinkage and related cracks that occur in the concrete slab-on- grades, flatworks and driveways depend on many factors, the most important of which is the amount of water in the concrete mix. The purpose of the slab reinforcement is to keep normal concrete shrinkage cracks closed tightly. The amount of concrete shrinkage can be minimized by reducing the amount of water in the mix. To keep shrinkage to a minimum the following should be considered: * Use the stiffest mix that can be handled and consolidated satisfactorily. * Use the largest maximum size of aggregate that is practical. For example, concrete made with %-inch maximum size aggregate usually requires about 40 lbs more (nearly 5 .gal.) water per cubic yard than concrete with 1-inch aggregate. * Cure the concrete as long as practical. The amount of slab reinforcement provided for conventional slab-on-grade construction considers that good quality concrete materials, proportioning, craftsmanship, and control tests where appropriate and applicable are provided. 9. A preconstruction meeting between representatives of this office, the property owner or planner, and the grading contractor I builder is recommended in order to discuss grading I construction details associated with site development. VIII. LIMITATIONS The conclusions and recommendations provided herein have been based on all. available data obtained from site observations, research and review of pertinent geotechnical reports and plans, subsurface exploratory excavations, as well as our experience with the soils and formational materials located in the general area. The materials encountered on the project site and utilized in laboratory testing are believed representative of the total area; however, earth materials may vary in characteristics between excavations. Of necessity we must assume a certain degree of continuity between exploratory excavations and I or natural exposures. It is necessary, therefore, that all observations, conclusions, and recommendations be verified during the grading operation. In the event discrepancies are noted, we should be contacted immediately so that an inspection can be made and additional recommendations issued if required. VINJE & MIDDLETON ENGINEERING, INC. 2450 Vineyard Avenue, #102, Escondido, California 92029-1229 • Phone (760) 743-1214 • Fax (760) 739-0343 GEOTECHNICAL INVESTIGATIONS GRADING SUPERVISION PERC TESTING ENVIRONMENTAL INVESTIGATIONS PRELIMINARY GEOTECHNICAL INVESTIGATION HILLSIDE DRIVE, CARLSBAD, CALIFORNIA PAGE 20 MARCH 5, 2003 The recommendations made in this report are applicable to th~ site at the time this report was prepared. It is the responsibility of the owner I developer to ensure that these recommendations are carried out in the field. It is almost impossible to predict with certainty the future performance of a property. The . future behavior of the site is also dependent on numerous unpredictable variables, such as earthquakes, rainfall, and onsite drainage pattems. The firm ofVINJE & MIDDLETON ENGINEERING, INC., shall not be held responsible for changes to the physical conditions of the property such as addition of fill soils, added cut slopes, or changing drainage patterns which occur without our inspection or control. The property owner(s) should be aware of the development of cracks in all concrete ·surfaces such as.floor slabs and exterior stucco associated with normal concrete shrinkage during the curing process. These features depend chiefly upon the condition of concrete and weather conditions at the time of construction and do not reflect detrimental ground movement. Hairline stucco cracks will often develop at window I door corners, and floor surface cracks up to %-inch wide in 20 feet may develop as a result of normal concrete shrinkage (according to the American Concrete Institute). This report should be considered valid for a period of one year and is subject to review by our firm following that time. If significant modifications are made to your tentative development plan, especially with respect to the height and location of cut and fill slopes, this report must be presented to us for review and possible revision. Vinje & Middleton Engineering, Inc., warrants that this report has. been prepared within the limits prescribed by our client with the usual thoroughness and competence of the engineering profession. No other warranty or representation, either expressed or implied, is included or intended. Once again, should any questions arise concerning this report, please do not hesitate to contact this office. Reference to our Job #03-145-P will help to expedite our response to your inquiries. VINJE & MIDDLETON ENGINEERING, INC. 2450 Vineyard Avenue, #102, Escondido, California 92029-1229 • Phone (760) 743·1214 • Fax (760) 739-0343 GEOTECHNICAL INVESTIGATIONS GRADING SUPERVISION PERC TESTING ENVIRONMENTAL INVESTIGATIONS PRELIMINARY GEOTECHNICAL INVESTIGATION HILLSIDE DRIVE, CARLSBAD, CALIFORNIA We appreciate this opportunity to be of service to you. VINJE & MIDDLETON ENGINEERING, INC. CEG #980 DM/SMSS/SJM/jt Distribution: Addressee. (5) c:/prelims. 03/03-145-P/jt PAGE 21 MARCH 5, 2003 VINJE & MIDDLETON ENGINEERING, INC. 2450 Vineyard Avenue, Escondido, California 92029-1229 • Phone (760) 743-1214 • Fax (760) 739-0343 GEOTECHNICAL INVESTIGATIONS GRADING SUPERVISION PERC TESTING ENVIRONMENTAL INVESTIGATION ..,_DELORME ~ 2002 DeLorme. Topo USA®. Data copyright of content owner. www.delorrne.corn "" 200 Scale 1 : 25.000 TN 1" = 2080 ft ~: •• e ,,. IOXI '"" ..., "" "" OXI ,.., i I i ' ' I, ' ·-.., / I I I / I ' I \ I ' ' ' ) ' ' ' : ' I I i ' ' : ' I 12 I I / i I I i i ; ' I r i ' I ' I ' ! I I ~ I I ---------------- -----------............................ ' \ \ \ \ \ \ \ \ SCALE: 1"=20' TEST TRENCH LOCATION ~-------\ \ .. _____________ _ ------------------------------...... ______ _ ----PLATE 2 JOB #03-145-P "" l I PRIMARY DIVISIONS GROUP SECONDARY DIVISIONS SYMBOL I I _J GRAVELS CLEAN GW Well graded gravels, gravel-sand mixtures, little or no fines. <( GRAVELS Cf) O:o MORE THAN HALF wo (LESS THAN GP Poorly graded gravels or gravel-sand mixtures, little or no fines. _J ~~ OF COARSE 0 5% FINES) I Cf) 20 FRACTION IS GRAVEL GM Silty gravels, gravel-sand-silt mixtures, non-plastic fines. 0 LLZW LARGER THAN WITH w Oz!::::! GC Clayey gravels, gravel-sand-clay mixtures, plastic fines. z LL<(Cf) NO.4 SIEVE FINES <( -liw CLEAN cc <(I-> SANDS sw Well graded sands, gravelly sands, little or no fines. I C) Iccw SANDS w zWCi5 MORE THAN HALF (LESS THAN Cf) <(CJ SP Poorly graded sands or gravelly sands, little or no fines. cc ICC OF COARSE 5% FINES) <( I-<( 0 w_J FRACTION IS SANDS SM Silty sands, sand-silt mixtures, non-plastic fines. I 0 cc~ SMALLER THAN WITH 0 NO.4 SIEVE sc Clayey sands, sand-clay mixtures, plastic fines. 2 FINES w ML Inorganic silts and very fine sands, rock flour, silty or clayey fine LLCC!::::l sands or clayey silts with slight plasticity. Cf) O:'JC!) SILTS AND CLAYS I _J CL 0 LL-lw LIQUID LIMIT IS Inorganic clays of low to medium plasticity, gravelly clays, sandy _J<(> Cf) <C2!:!:! clays, silty clays, lean clays. 0 IC!)Cf) LESS THAN 50% w ZC!)O OL Organic silts and organic silty clays of low plasticity. z I <( <(-o I-lC\J MH Inorganic silts, micaceous or diatomaceous fine sandy or silty cc I-<( . SILTS AND CLAYS soils, elastic silts. C) wO:O w ccWZ LIQUID LIMIT IS CH Inorganic clays of high plasticity, fat clays. z o~z I u::: 22~ GREATER THAN 50% I-OH Organic clays of medium to high plasticity, organic silts. HIGHLY ORGANIC SOILS PT Peat and other highly organic soils. I GRAIN' SIZES U.S. STANDARD SERIES SIEVE CLEAR SQUARE SIEVE OPENINGS 200 40 10 4 3/4" 3" 12" SAND GRAVEL I SILTS AND CLAYS COBBLES BOULDERS FINE I MEDIUM I COARSE FINE I COARSE I RELATIVE DENSITY CONSISTENCY !sANDS, GRAVELS AND BLOWS/FOOT CLAYS AND STRENGTH BLOWS/FOOT NON-PLASTIC SILTS PLASTIC SILTS ' I VERY SOFT 0-Y. 0-2 VERY LOOSE 0-4 SOFT y. -y, 2-4 LOOSE 4-10 MEDIUM DENSE 10-30 FIRM y, -1 4-8 DENSE 30-50 STIFF 1 - 2 8-16 VERY STIFF 2-4 16-32 VERY DENSE OVER 50 HARD OVER 4 OVER 32 1 . Blow count, 140 pound hammer falling 30 inches on 2 inch O.D. split spoon sampler (ASTM D-1586) 2. Unconfined compressive strength per SOIL TEST pocket penetrometer CL-700 " Sand Cone Test II I 24 = Standard Penetration Test (SPT) (ASTM D-1586) J Bulk Sample 6 with blow counts per 6 inches D Chunk Sample 0 Driven Rings II 24 6 = California Sampler with blow counts per 6 inches ~-~~"""~--~-- VINJE & MIDDLETON KEY TO EXPLORATORY BORING LOGS Unified Soil Classification System (ASTM D-2487) ENGINEERING, INC. 2450 Vineyard Ave., #1 02 Escondido, CA 92029-1229 PROJECT NO. KEY Date: 1-30-03 Logged by: SJM T-1 DRY RELATIVE DEPTH SAMPLE uses MOISTURE DENSITY COMPACTION (ft) DESCRIPTION SYMBOL (%) (pcf) (%) --TERRACE DEPOSIT: - 1 -0 Sandstone. Red-brown color. Medium grained. Dry. SP 2.9 98.1 83.7 - -Weathered loose. - 2 -o• - -At 2', becomes weathered friable, dry to moist. Poorly 3.4 97.9 83.6 - 3 -cemented. Locally porous. -- - 4 -0 At 3' ' becomes moderately blocky and moderately 2.5 97.6 83.3 - -cemented. Medium dense to dense. - 5 -0 1.8 95.5 81.5 -- - 6 -0 ST-1 3.9 105.9 90.4 - 7 -End Test Trench at 6%'. --No caving. No groundwater. -8) - -- - 9 - Date: Logged by: DRY RELATIVE DEPTH SAMPLE uses MOISTURE DENSITY COMPACTION (ft) DESCRIPTION SYMBOL (%) (pcf) (%) -0 - - - -- -- -- -5 - -- - - --~ -- -10- -- - - -- -- -15- - - -- VINJE & MIDDLETON ENGINEERING, INC ·. / ~·;; · . .;;;;;;,. • !?iJiS>i''· .)· ; ?E~Y • / • ·. . ' ·'· • ,::; •. r~ •. ?· .. '""'' TmStfJ:TReNeH lOGS •· ;i •. ·::) .• ~:./ 1'.;'{; / ·' .... ; ,\. 0;.:;.:: \i >i) ) : < .· 2450 Vineyard Avenue, Suite 102 CARLSBAD Escondido, California 92029-1229 HILLSIDE DRIVE, Office 760-743-1214 Fax 760-739-0343 PROJECT NO. 03-145.,P PLATE 3 ... Sand Cone Test • Bulk Sample 0 Nuclear Test 0 Driven Rings -. -~ ... ,(!) ·>.o- ' ' ' ':1 (!) (!) 0 ' ' 30 20 10 0 30 MILES FAULT -EPICENTER MAP SAN DIEGO COUNTY REGION INDICATED EARTHQUAKE EVENTS THROUGH 75 YEAR PERIOD (1900-1974) Map data is compiled from various sources including California Division of Mines and Geology, California Institude of Technology and the National Oceanic and Atmospheric Administration. Map is reproduced from California Division of Mines and Geology, "Earthquake Epicenter Map of California; Map Sheet 39." Earthquake Magnitude c ..•..••..••.• 4.0 TO 4.9 PROJECT: __ ~J=o~b~#=03~-~14~5~-P~------------ (!) ............ 5.0 TO 5.9 C) ............ 6.0 TO 6.9 HILLSIDE DRIVE. CARLSBAD C) .......... 7.0 TO 7.9 PLATE:~---------=4 ______________ __ -----···· Fault. Waterproofing RETAINING WALL DRAIN DETAIL Typical -no scale · · Granular, non-expansive · · backfill. Compacted.:· · "' .. . 1. .. l Filter Material. Crushed rock (wrapped in filter fabric) or Class 2 Permeable Material (see specifications below) Competent, approved soils or bedrock CONSTRUCTION SPECIFICATIONS: 1. Provide granular, non-expansive backfill soil in 1:1 gradient wedge behind wall. Compact backfill to minimum 90% of laboratory standard. 2. Provide back drainage for wall to prevent build-up of hydrostatic pressures. Use drainage openings along base of wall or back drain system as outlined below. 3. Backdrain should consist of 4" diameter PVC pipe (Schedule 40 or equivalent) with perforations down. Drain to suitable outlet at minimum 1%. Provide%" -1W' crushed gravel filter wrapped in filter fabric (Mirafi 140N or equivalent). Delete filter fabric wrap if Caltrans C.lass 2 permeable material is used. Compact Class 2 material to minimum 90% of laboratory standard. 4. Seal back of wall with waterproofing in accordance with architect's specifications. 5. Provide positive drainage to disallow pending of water above wall. Lined drainage ditch to minimum 2% flow away from wall is recommended. * Use 1 Y, cubic foot per foot with granular backfill soil and 4 cubic foot per foot if expansive backfill soil is used. VINJE & MIDDLETON ENGINEERING, INC. PLATE 5 NOTES: ISOLATION JOINTS AND RE-ENTRANT CORNER REINFORCEMENT Typical -no scale (a) (b) ISOLATION JOINTS CONTRACTION JOINTS RE-ENTRANT CORNER-----. REINFORCEMENT NO. 4 BARS PLACED 1.5'' BELOW TOP OF SLAB (c) RE-ENTRANT CORNER CRACK 1. Isolation joints around the columns should be either circular as shown in (a) or diamond shaped as shown in (b). If no isolation joints are used around columns, or if the corners of the isolation joints do not meet the contraction joints, radial cracking as shown in (c)may occur (reference ACI). 2. In order to control cracking at the re-entrant corners (±27QP corners), provide reinforcement as shown in (c). 3. Re-entrant corner reinforcement shown herein is provided as a general guideline only and is subject to verification and changes by the project architect and/or structural engineer based upon slab geometry, location, and other engineerin:g and construction factors. VINJE & MIDDLETON ENGINEERING, INC. PLATE 6 JUN 0 6 2003 ENGINEERING DEPARTMENT j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j I j j