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Home My WebLink About3151; Palomar Airport Road Widening; Geotechnical Consulting Palomar Airport Road; 1987-04-22Testing Engineers—San Diego A Division of United States Tesfing Company, Inc. 3467 Kurtz St.. P.O. Box 80985. San Diego. Ca. 92138(619) 225-9641 2956 Industry Street. Oceanside. California 92054 (619) 757-0248 April 22, 1987 Job No. 7092 City of Carlsbad Community Development 2075 Las Palmas Drive Carlsbad, California 92008 Attention: Subject: Mr. Al Virgilio Geotechnical Consulting Clarification of Elements Regarding Palomar Airport Road Widening Report Carlsbad, California Referenced Report: Referenced Letter: m m "Geotechnical Consulting Palomar Airport Road Widening Carlsbad, California," by Testing Engineers-San Diego, dated March 3, 1987 "Geotechnical Consulting Palomar Airport Road Widening," by Pountney and Associates, Inc., dated March 30, 1987 m m m Palomar Airport Road Widening Page No. 2 Carlsbad, California April 22, 1987 Dear Mr. Virgilio: This is in response to the referenced letter written by Pountney & Associates, Incorporated regarding our report on the project. During the process of study, limited contact was made between Testing Engineers and the other company in discussing the items to be considered, and its general format. As a result, Pountney and Associates wrote the letter asking for clarification and the following is discussed for each of the items: SECTION 1.1 1. "The near surface, saturated, alluvial soil, whenever encountered, should be removed to a minimum depth of three feet" is a general construction recommendation. SECTION 1.2 2. "Soil adjacent to the roadway should be excavated and recompacted. The excavation should extend to at least ten feet (10') from the outside edges of the roadway". A roadway is in this definition the pavement section, from curb to curb. This excavation and recompaction is intended to give lateral support to the soil under the pavement, to provide protection from erosion and reduce water seepage, as explained in the report. m Palomar Airport Road Widening Page No. 3 Carlsbad, California April 22, 1987 SECTION 1.3 m 3. The Benching requirement refers to downslope fills. m ^ SECTION 1.4 ^ 4. The soil removal is mentioned in the two sections. Section 1.1 is refering to the * excavation of local pockets of soft and saturated soils wherever encountered. Section ^ 1.4 is referring to loose and/or compressible ^ existing top soil which is to be removed uniformely. Unless the soil is saturated, m removal should be limited to two foot thickness. m SECTION 1.8 m m 5. Permanent cut and fill slopes should be inclined at no steeper than 2 to 1 (horizontal to vertical). SECTION 2.2 mm 6. In our rough draft of the report, two alternatives including a retaining wall and a crib wall were mentioned. Prior to issuance of our final report, we deleted the crib wall m alternative without deleting the "above alt'ernatives". SECTION 3.1 m ^ 7. We understand there was no specific requirement that the pavement be designed for «• a Traffic Index (TI) value of 9. La Costa Avenue, another important project was designed for a T.I. value of 8. So we assumed the same ^ for Palomar Airport Road. Palomar Airport Road Widening Page No. 4 Carlsbad, California April 22, 1987 If TI of 9 is to be used, then an asphalt concrete thickness and crushed aggregate base of 6 inches and 15 inches, repectively, could be used. The City of Carlsbad requires a minimum section of 6 and 18 inches, respectively. A detour pavement section of 4 inches asphalt concrete and 8 inches of aggregate base may be used. SECTION 3.2 8. This section was included because we understand that grading would generate excess material and we suggested that the clay be exported and the on-site granular soil be used in the roadway. We had a discussion about all the above items with Mr. Jay F. Olsen in our meeting on April 10, 1987 and have come to a better understanding. In summary, we feel that the overall recommendations in the report cover most of the necessary design parameters as well as construction techniques. All of the above questions could have been clarified easily with better communication. We hope our contact will improve in the future. m Palomar Airport Road Widening Carlsbad, California Page No. 5 April 22, 1987 m The opportunity to be of service is appreciated, and if you have any additional questions regarding this project, please do not hesitate to contact us at your convenience. AF/eh Addressee (2) Respectfully submitted, TESTING ENGINEERS-SAN DIEGO Almaz FesTseha Project Engineer •m m •m m Testing Eng/neers—San Diego A Division of United States Testing Company, inc 3467 KurtzSt., P.O. Box 80985. SanDiego. Ca. 92138(619)225-9641 ^ 2956 Industry Street, Oceanside. California 92054 (619) 757-0248 City of Carlsbad Community Development 2075 Las Palmas Drive Carlsbad, California 92008 Attention: Subject: Mr. Al Virgilio May 22, 1987 Job No. 7092-1 RECEI V.:.D fz-ay ^. r. 1937 MUNICIPAL PROJECTS DIVISION Supplementary Geotechnical Consulting Services Palomar Airport Road East of Paseo Del Norte Carlsbad, California Gentlemen: This report presents results of our additional soil investigation and pavement section design of the subject site. The purpose of the soil investigation was to retain bulk soil samples to be used in the laboratory for "R"-value tests. These actual "R"-value test results were then used to estimate the various pavement sections presented herewith. Subsurface conditions were explored by drilling ten 8-inch diameter test borings with a Mobile B-61 drill rig, to 4 to 20 feet depths. A staff geologist from our office was present during the drilling of the test borings. The sample locations and soil types with the respective "R"-value results are presented in Table I. fl •m inn •.m Palomar Airport Road East of Paseo Del Norte Carlsbad, California Page No. 2 May 22, 1987 Job No. 7092--1 m M TABLE I •m m Bore Hole No. Bore Hole Location Sample Depth Feet Soil Type R-Val: •m m 1 30+00 8 Sandy clay 12 2 32+50 13 Sandy clay 13 m 3 36+00 12-15 Sandy clay 9 4 36+00 18-20 Sandy clay 8 m nm 5 40+00 7 Gravelly Refusal @ 7 ft. MM 6 42+00 7 Sandy clay 6 7 50+00 2-4 Silty sand 47 ^mm 8 53+00 4-6 Clayey sand 21 9 72+50 5 Silty sand 57 'im 10 85+00 6-8 Silty clay 27 Palomar Airport Road Page No. 3 East of Paseo Del Norte May 22, 1987 Carlsbad, California Job No, 7092-1 ASPHALTIC CONCRETE DESIGN Based on the R-value results and a T.I. value of 9 for primary arterial, as required by the City of Carlsbad, alternate structural sections are computed. For purposes of section design, "R"-value results have been separated to represent three zones of the alignment. The results are summarized and presented on Table II. The design assumes a minimum asphaltic concrete thickness of 6 inches and processed Class II aggregate base course. If the three layer conventional system is preferred, we recommend disintegrated granite (D.G.) with minimum "R"-value of 50 to be used as select import for a subbase course. m m m •m Palomar Airport Road East of Paseo Del Norte Carlsbad, California Page No. 4 May 22, 1987 Job No. 7092-1 TABLE NO, II RECOMMENDED SECTION DESIGN ALTERNATIVES m Materials are referenced to Cal Trans Standard Specifications for aggregate subbase, aggregate base, and asphaltic concrete Zone 1: Station 27+00 to Station 32+50 Basement Soil R-Value 12 Traffic Index (Prime Arterial) 9 Minimum a.c. Thickness, ft. (inch) 0.5' (6") Minimum cover required (GE) ft. (inch) 2.55 Alternative 1: Conventional 3 Layer Svstem: Actual Thickness Feet Inch Course Gf) Gravel Equivalent (GE) Feet 0.50 6 0.83 10 0.75 9 Asphaltic Concrete Class II Agg. Base Agg. Subbase (R=50; 1,80 1.10 1.00 2.08 25 Alternative 2: Conventional 2 layer Svstem: 0,50 6 Asphaltic Concrete 1.80 1-50 18 Class II Agg. Base 1.10 2.00 24 0,90 0,91 0.75 2,56 0.90 1.65 2.55 Palomar Airport Road Page No. 5 East of Paseo Del Norte May 22, 1987 Carlsbad,.California JobNo. 7092-1 Zone 2: Station 32+50 to Station 50+00 Basement Soil R-Value 6 Traffic Index (Prime Arterial) 9 Minimum a.c. Thickness, ft. (inch) 0.5' (6") Minimum cover required (GE) ft. (inch) 2.70 Alternative 1: Conventional 3 Layer Svstem: Actual Gravel Thickness Equivalent (GE Feet Inch Course (Gf) peet 0.50 6 Asphaltic Concrete 1.80 0.90 0.83 10 Class II Agg. Base 1.10 0.91 0.92 11 Agg. Subbase (R=50) 1,00 0.92 2.25 27 2773 Alternative 2: Conventional 2 layer Svstem: 0.50 6 Asphaltic Concrete 1.80 0.90 1-67 20 Class II Agg, Base 1.10 1.83 2.17 24 2773 Note: Based on the "R"-value results and uniform soil type at Station 36+00, either of the above asphaltic pavement sections can be utilized at 17 feet road level. The "R"-value shown on Table I should be verified after grading. Palomar Airport Road East of Paseo Del Norte Carlsbad, California Page No. 6 May 22, 1987 Job No. 7092-1 •HI Zone 3: Station 50+00 to Station 85+00 m m mi Basement Soil R-Value Traffic Index (Prime Arterial) Minimum a.c. Thickness, ft. (inch) Minimum cover required (GE) ft. (inch) 21 9 0.5' (6") 2,28 m Alternative 1: Conventional 3 Layer System: m Actual Thickness Feet Inch Course (Gf) Gravel Equivalent Feet (GE) m 0,50 6 Asphaltic Concrete 1.80 0.90 •m 0,50 6 Class II Agg, Base 1.10 0.55 m 0.83 10 1.83 22 Agg. Subbase (R=50) 1.00 0.83 2.28 Alternative lA: •m Actual Thickness Feet Inch Course (Gf) Gravel Equivalent Feet (GE) 0.50 6 Asphaltic Concrete 1.80 0,90 0,83 10 Class II Agg. Base 1.10 0.91 0.50 6 1.83 22 Agg. Subbase (R= 5 0) 1,00 0.50 2,31 Alternative 2: Conventional 2 laver Svstem: 0.50 6 Asphaltic Concrete 1.80 0.90 m 1.25 15 1.75 21 Class II Agg. Base 1.10 1,38 2.28 Palomar Airport Road Page No, 7 * East of Paseo Del Norte May 22, 1987 Carlsbad, California Job No, 7092-1 The samples taken are assumed to be representatives of the material which will be immediately under the planned structural section. The design is based on the lowest "R"-value for that zone since it represents the lowest quality material encountered. The asphaltic pavement sections recommended reflect our best estimate of the project requirements based on an evaluation of the subsurface soil conditions encountered at the exploration locations and the assumption that the soil conditions do not deviate appreciably from those encountered. Any unusual conditions, not covered in this report, encountered during site development, should be brought to the attention of the soil engineer. The "R"-value results should also be verified before construction, so that modifications can be made if necessary. This office should be advised of any changes in the project scope or proposed site grading so that it may be determined if the recommendations contained herein are appropriate. Palomar Airport Road East of Paseo Del Norte Carlsbad, California Page No. 8 May 22, 1987 Job No. 7092-1 We appreciate the opportunity to be of service to you on this project and look forward to a continued association on this and future projects. If you have any questions, please do not hesitate to contact our office. Almaz F^seha Project Engineer Respectfully submitted, TESTING ENGINEERS-SAN DIEGO Thomas H. Chapman, RCE 34228 Vice President THC/AF/eh Addressee (2) cc: Jay F. Olsen Testing Eng/neers—San Diego A Division ot United States Testing Company. Inc. 3467 KurtzSt.. P.O. Box 80985. SanDiego. Ca. 92138(619)225-9641 2956 Industry Street. Oceanside, California 92054 (619) 757-0248 City of Carlsbad Community Development 2075 Las Palmas Drive Carlsbad, California 92008 Attention: Mr. Al Virgilio March 3, 1987 Job No. 7092 Subject: Geotechnical Consulting Palomar Airport Road Widening Carlsbad, California Gentlemen: As per your request and authorization, we have completed a geotechnical investigation of the proposed Palomar Airport Road alignment. The purpose of this investigation was to perform a geotechnical and geological evaluation of the above-mentioned roadway widening and to provide geotechnical design criteria for the planned widening. This investigation was authorized by your acceptance of our proposal dated December-23, 1986. Our office conducted a field investigation and soil samplings of the site. The soil samples were then used for laboratory testing in our office. The results of the field exploration and laboratory testings are included herewith. City of Carlsbad Palomar Airport Road Widening Page 2 March 3, 1987 Job No. 7092 We appreciate the opportunity to be of service to you on this interesting project and look forward to a continued association on this and future projects. If you have any questions regarding this report, please contact us at your convenience. Almaz Fesseha Project Engineer AF/SMP:svc Addressee (6) Respectfully submitted, TESTING ENGINEERS-SAN DIEGO William Schill Project Geologist Stephen M. Poole, RCE 40219 Geotechnical Department Manager TABLE OF CONTENTS m Page INTRODUCTION 1 PROJECT DESCRIPTION 1 * METHOD OF INVESTIGATION 1 LABORATORY TESTINGS 2 m GEOLOGIC CONDITIONS 3 FILL 3 LINDA VISTA FORMATION (Qlvs) 4 * SANTIAGO FORMATION (Tsa) 4 DEL MAR FORMATION (Tdts) 4 ^ DISCUSSION AND CONCLUSIONS 5 RECOMMENDATIONS 7 GENERAL 7 RETAINING WALLS 11 NEW ASPHALT CONCRETE PAVEMENT 13 ^ REVIEW 15 LIMITATIONS AND UNIFORMITY OF CONDITIONS 16 ENCLOSURES: BORING LOGS PLATE 1-6 TEST PIT LOG PLATE 7-12 SYMBOLS & TERMS USED ON BORING LOGS PLATE 13 GENERALIZED -SUBSURFACE PROFILE PLATE 14 UNIFIED SOIL CLASSIFICATION PLATE 15 APPENDIX LABORATORY TEST DESCRIPTION LABORATORY TEST RESULTS m m City of Carlsbad Page 1 Palomar Airport Road Widening March 3, 1987 Job No. 7092 INTRODUCTION PROJECT DESCRIPTION The subject site extends from east of Paseo Del Norte at about Station 27+00 to west of Palomar Oaks Way at about Station 94+50, METHOD OF INVESTIGATION Site materials within the area of the proposed improvements were evaluated by geologic mapping of surface exposures, backhoe excavated test pits, and auger drilled test borings. The excavations provided opportunities to evaluate subsurface conditions, and enabled geologists to collect samples for laboratory analysis. The approximate test boring and test pit locations are presented on the logs. Boring logs are presented on Plates 1 through 6 and Test Pit logs are presented on Plates 7 through 12. Symbols and terms used on the Test Pit and Boring Logs are presented on Plate 13. A generalized subsurface profile is presented on Plate 14. The number of blows required to drive the sampling barrel into the soil was recorded on the boring logs. City of Carlsbad Page 2 Palomar Airport Road Widening March 3, 1987 Job No. 7092 LABORATORY TESTING Soils were visually classified according to the Unified Soil Classification System as presented on Plate 15. Laboratory tests were performed in accordance with accepted test methods of « the American Society for Testing and Materials (ASTM). Tests conducted for the project included: Moisture/Density and Expansion. The Test Results and Test Descriptions are presented •mm in the Appendix. HI mm M 4m mn •M JH City of Carlsbad Page 3 Palomar Airport Road Widening March 3, 1987 Job No. 7092 GEOLOGIC CONDITIONS The subject site lies in the Peninsula Range geomorphic province and is underlain by formational materials of Eoceme age. The Linda Vista formation was encountered on the north side of Palomar Road at the higher elevations. During the proposed roadway grading, natural soil and rock material will be encountered during construction. According to a study done by Weber entitled. Recent Slope Failures, Ancient Landslides, and Related Geolocry of the North-Central Coastal Area, San Diego County, California 1982, the geologic units in question are thought to be stable. FILL The fill materials encountered in Test Pit 1 and 2 are thought to be local in nature because of the resemblance to the soils generated from adjacent formational material. Fill materials encountered are mostly sandy silt. mt mt City of Carlsbad Page 4 Palomar Airport Road Widening March 3, 1987 Job No. 7092 LINDA VISTA FORMATION (Qlvs) This formation was encountered in Test Pit 6 and can be expected mt on the north side of Palomar Airport Road. This sub-unit lies ^ closer to the coast where it can be observed in some road cuts „ (Weber 1902). Materials that can be expected to be generated are clayey sands, sands, and small cobbles and pebbles. SANTIAGO FORMATION (Tsa) mm m» This sub-unit consists in varying proportions of silty sand, sand, clayey-silt, and clayey sands. The formation is exposed on the north side of Palomar Airport Road. •am DEL MAR FORMATION (Tdts) -">• The rocks of this sub-unit underlie the site where they in turn overlie granite and metamorphic rocks. The materials generated •HI from these formations will be silty sands, clayey sands, and „ clayey silts. Claystone units are thin, but may be encountered « during excavations. City of Carlsbad Page 5 Palomar Airport Road Widening March 3, 1987 Job No. 7092 DISCUSSION AND CONCLUSIONS Based on our field observations, analyses of technical data generated in this study, and our geotechnical point of view, the site is suitable for the proposed project. The planned roadway alignment is underlain by existing road fill soil and several natural earth deposits which range from soft, saturated soils to hard, cemented formational rocks. Due to the soft and saturated nature, some soil layers may have a potential for settlement. However, the alluvium in the valley is medium-dense to dense, so minimum undercutting and recompacting can be expected. Portions of the hillside, need stabilization against surficial failure or sliding. Various methods were considered. One way is to provide a sufficiently flat slope, depending on the existing earth material. A minimum safe slope of two horizontal to one vertical can be used. It is however, noted, that adverse bedding may be present within the slope. The other alternative is building retaining walls or a combination of retaining walls, MM City of Carlsbad Page 6' Palomar Airport Road Widening March 3, 1987 Job No. 7092 benching, and sloping the soil above the walls. This will reduce the height of the retaining wall. Crib walls can also be used though, more excavation work will be reguired, making the solution costly. City of Carlsbad Page 7 Palomar Airport Road Widening March 3, 1987 Job No. 7092 RECOMMENDATIONS * The following section presents recommendations consistent with the underlying soil/rock units relative to the planned grades: m m 1- General 1.1 The near surface, saturated, alluvial soil, * whenever encountered, should be removed to a minimum depth of three feet (3') and replaced with site soil or base materials having ^ acceptable moisture contents. This replaced - soil should be compacted to a dry density of at least ninety percent (90%) of the laboratory Standard (ASTM Test Method, D-1557), and should be free of debris, organic m materials, or boulders. m tf 1.2 Soil adjacent to the roadway should be excavated and recompacted. The excavations should extend at least ten feet (10') from the tf outside edges of the roadway. This will City of Carlsbad Page 8 Palomar Airport Road Widening March 3, 1987 Job No. 7092 minimize settling and cracking of the roadway and contribute to reducing water seepage under the pavement. 1.3 When fill is to be placed and compacted against hillsides or existing fill, the slopes of original hillsides and old or new fills shall be horizontally benched to key the fill material into the adjacent ground. 1.4 Based upon the blow counts per foot recorded in the drilling operation, we found the alluvium soils encountered in the valley to be in medium-dense to very dense in condition. Therefore, excavation and recompaction may be limited to the upper two feet (2') of alluvium soil prior to placement of structural fill. 1.5 Drainage and positive surface gradients should be provided so that surface water will not pond on the pavements, shoulder areas, nor foundations. City of Carlsbad Page 9 Palomar Airport Road Widening March 3, 1987 Job No. 7092 1.6 Support of open trenches: All trenches excavated in excess of five feet in depth should either be adequately shored or laid back on a slope of one horizontal to one vertical. In areas where sand is encountered, the slope should be flattened to 2 horizontal to 1 vertical. On-site inspection by a representative of this office may result in modification based on actual field exposures. 1.7 Trench Backfill: Pipeline trenches should be backfilled with compacted fill. Backfill materials should be placed in lift thicknesses appropriate to the type of compaction equipment utilized and compacted to a minimum degree of compaction 90 percent by mechanical means. In pavement areas, portions of the trench backfill within the pavement section should conform to the material and compaction requirements of the adjacent pavement section. City of Carlsbad Page 10 Palomar Airport Road Widening March 3, 1987 Job No. 7092 1.8 The hillside slope, may be stabilized by providing adequate slopes depending on the existing earth -material. If temporary slopes are reguired in the sandstone material, then a minimum slope of one horizontal to one vertical (1:1) may be used. Wherever sandy soil is encountered, a slope of two horizontal to one vertical (2:1) may be used. These slopes, if greater than twenty feet (20') high should be benched or stepped. However as noted earlier, adverse bedding may be present within the slope, and should be inspected. The slopes may be evaluated on-site by a representative of this office, based on actual site inspections. City of Carlsbad Page 11 Palomar Airport Road Widening March 3, 1987 Job No. 7092 2. Retaining Walls Retaining walls may also be used, as an alternative, to the slope stabilization on the hillside area. 2.1 The retaining walls if preferred, should be properly designed and be founded at least 24 inches below the lowest adjacent grade. For design purposes, a static, lateral earth pressure (active case) may be approximated using an equivalent fluid unit weight of 35 pounds per cubic foot. Drainage behind the retaining wall should be adequate to ensure that free moisture does not accumulate near the wall. A coefficient of friction 0.35 times the dead load may be used between the bearing soils and concrete wall foundations, 2.2 The foundations of the retaining walls can be designed for a safe allowable bearing value of two thousand pounds per sguare foot (2000 psf), for both of the above alternatives. m City of Carlsbad Page 12 Palomar Airport Road Widening March 3, 1987 Job No. 7092 2.3 When building the retaining walls, the excavated hillside slope should be stabilized for safety against sliding or caving. A temporary slope gradient of one horizontal to one vertical (1:1) may be used for the sandstone zones. This slope should be evaluated, on-site, by a representative of this office based on actual site inspections. 2.4 After backfilling the excavated area behind the retaining wall, the slope above the wall should have a minimum gradient of one and a half horizontal to one vertical (1-1/2:1). City of Carlsbad Page 13 Palomar Airport Road Widening March 3, 1987 Job No. 7092 3. New Asphaltic Concrete Pavement m ^ 3.1 The new asphaltic pavement section for the widening of the road comprises of Class II base and ** asphaltic concrete. The design was based on a minimum "R"-value of the base material of 78 and a ^ subbase material of 10. For a traffic index (TI) ^ of 8, a minimum asphaltic concrete thickness of • four inches and a base material thickness of twenty inches may be used. Alternatively, a full depth mm asphaltic concrete section, twelve inches (12") ^ thick, may be constructed on the existing subgrade material. am 3.2 The site is expected to have a net export of soil. All clay soils under base coarse may be removed and ^ replaced with sand compacted as required by ASTM Test Method D-1557. If clay soils are not removed, * we then recommend that granular soils be placed in the upper three feet (3') of fill. The pavement tf maintenance should be minimized if granular soils _ are placed beneath the Class II base. City of Carlsbad Page 14 " Palomar Airport Road Widening March 3, 1987 Job No. 7092 3.3 The placement and construction of the pavement section, should be in confonnance with an appropriate standard specification, such as "Standard Specification for Public Works." 3.4 The overall design of the pavement should include proper drainage systems and gradients for runoff flow away from the roadway. Also, proper channeling systems should be designed to prevent ponding of water that may promote seepage beneath the pavement. City of Carlsbad Page 15 Palomar Airport Road Widening March 3, 1987 Job No. 7092 REVIEW The final plans should be reviewed by this office to minimize any misunderstandings between the plans and the recommendations presented herein. In addition, excavations and earthwork performed on-site should be evaluated by a qualified engineering geologist or geotechnical engineer. If conditions are found to vary from those stated herein, appropriate recommendations should be requested. City of Carlsbad Page 16 Palomar Airport Road widening March 3, 1987 Job No. 7092 LIMITATIONS AND UNIFORMITY OF CONDITIONS The recommendations presented in this report are contingent upon our review of final plans and specifications. It is recommended that testing Engineers-San Diego, be retained to provide continuous soil engineering services during the earthwork operations. This is to observe compliance with the design concepts, specifications, or recommendations and to allow design changes in the event that subsurface conditions differ from those anticipated prior to the start of construction. The recommendations and opinions expressed in this report reflect our best estimate of the project requirements based on an evaluation of the subsurface soil conditions encountered at the exploration locations and the assumption that the soil conditions do not deviate appreciably from those encountered. It should be recognized that the performance of the foundations and/or cut and fill slopes may be influenced by undisclosed or unforeseen variations in the soil conditions that may occur in City of Carlsbad Page 17 Palomar Airport Road Widening March 3, 1987 Job No. 7092 the intermediate and unexplored areas. Any unusual conditions not covered in this report that may be encountered during site development should be brought to the attention of the soil engineer so that modifications can be made, if necessary. This office should be advised of any changes in the project scope or purposed site grading so that it may be determined if the recommendations contained herein are appropriate. The findings of this report are valid as of this date. Changes in the condition of a property can, however, occur with the passage of time, whether they be due to natural processes or the work of man on this or adjacent properties. Due to such changes, the findings of this report may be invalidated wholly or in part by changes beyond our control. Therefore, this report would not be relied upon after a period of two years without a review by us verifying the suitability of the conclusions, and recommendations. City of Carlsbad Page 18 Palomar Airport Road Widening March 3, 1987 Job No, 7092 The client recognizes that subsurface conditions may vary from those encountered at the locations where our test pits, surveys, and explorations are made, and that our data, interpretations, and recommendations are based solely on the information obtained by us. Our services consist of professional consultation and observation only, and no warranty of any kind whatsoever, expressed or implied, is made or intended in connection with the work performed or to be performed by us, or by our proposal for consulting or other services, or by our furnishing of oral or written reports, or findings. It is the responsibility of the owners, or their representatives to ensure that the information and recommendations contained herein are brought to the attention of the engineer and architect for the project and incorporated into the project's plans and specifications. It is further their responsibility to take the necessary measures to ensure that the contractor and his subcontractors carry out such recommendations during construction. Testing Engineers-San Diego BORING LOG Project: Airport Rd-nntp. 1-23-87 Bering No: B-61 Hole ninmirtftr. 8 inches cs o Type of Rig: Hammer Weight a Fall: 140 lbs./30" Ground Water: none Elevation: _ - Logged By WMS Location: Sta: 55+50 50' North of Centerline FIELD DESCRIPTION CO o < cn 5? O 8 O o CNJ I . 4 . 6 . 8 - 10 • 12 . 14 • 16 - 18 20 - 22 - 24 . 26 28 SC ML ML Formational 0-7 Clayey Sand, tan to brown, fine to medium grained sand, moist, medium dense DR 35 7-18' Sandy Silt with Clay, dark brown, fine to medium grained sand, moist, stiff to very stiff. 27 DR 18-43' Clayey Silt, white to tan-brown, variable' clay content, dry to moist, very stiff to hard 50-6" Decreasing clay concent more brown in color 50-2" DR PLATE. tk Testing Engineers-San Diego BORING LOG CM O o. Project: Palomar A^•^-pn•r^ Type of Rig; ^=hl Date: Hole Diometer- 8 inches Boring No: J. Elevation Hommer Weigh! a Pmi-140 ibs./30"— Ground Water: none Logged By: Location: Sta: 55+50 50' North of Centerline FIELD DESCRIPTION tn < cn Z U. s IK cn O 8 O O CJ I 32 34 36 38 40 42 44 46 • 48 - 50 . 52 - 54 - 56 . 58 ML 50-2" DR 128 50'2" DR Boring Terminated at 44 feet. Testing Engineers-San Diego BORING LOG Project: Palomar Airport Rd.nni,. 1-23-87 goring No: I Type of Rig:±11: Hole nigmetef. 8 inches Elevation: CM O Hammer Weight a Fnii-i^Q ibs./3Q" Q^Qy^j Wntnf None ^^^^^ gy. WMS a. tn Location: Sta: 27+90, 60' South of Center line FIELD DESCRIPTION CO Q tn CO .— Z 1^ >-a: o cn o UJ 8 O O CJ I . 2 . 4 , 8 .10 •12 M 16 •18 .20 •22 ML 0-4' Sandy Silt, brown, medium to fine sand SM SC SP SM 4-8' Silty Sand, light brown, medium to fine sand, moist 51 8-12' Clayey _ Sand, dark brown, medium to fine sand, moist 61 12-17* Sand, red-brown, medium to fine grained, clean, moist 71 17-21.5' Silty Sand, dark brown, medium to fine grained, moist, dense to very dense Boring Terminated @ 21.5' DR 100 DR DR PLATE. Testing Engineers-San Diego BORING LOG Project Type 0 Hamme . Palomar Airoort RdCVila. 1-23-87 Bnrinn Nn-Project Type 0 Hamme F Riq. B-61 Hnl« ninmAter- 8 inches Elevation - Project Type 0 Hamme r WAir]ht ft Fnll- 140 lbs/30" firnimH W^tfr-20.5' Logged By: WMS u. Location: Sta: 4i-K)0, 130' South of Center line Ik 55 — «i 8 DEPTH 1 SYMBOL FIELD DESCRIPTION BLOWS/ SAMPLE DRY DEt (PCI MOISTUf CONTENl o o CNJ 1 - 2 ML 0-3' Sandy Silt, light brown fine sand, minor clay, moist, firm 4 LI 3-9' Sandy Clay, dark brown to black, medium to fine sand, moist, very stiff 6 - 8 43 DR 114 15 • 10 ML 9-20.5' Sandy Silt , light brown, fine • 10 sand, moist, hard 92 DR 114 15 . 12 . 14 - 14' Lighter brown - 16 - 18 - - 20 m 22 SM 20.5-24' Silty Sand, Brown, wet. dense 80-6" DR - 24 . 26 ML 24-30' Sandy Silt, brown, fine sand, dry to moist, hard m 28 Boring Terminated (a 30' 00-3" DR ON O PLATE, Testing Engineers-San Diego CN ON o p- BORING LOG Project: Palomar Airport Rdi^^^. 1-23-87 Boeing NO: Type of Rig: B-61 ^ole Diomfltftr- 8 inches Elevotion: Hammer Weigh! a Falh^^Q ibs./30" Q^Q^^J, Water: Ji22i_ Logged By: DEPTH (FT) 1 SYMBOL Location: Sta: 71+40, 70' South of Center line FIELD DESCRIPTION BLOWS/FT SAMPLE 1 ORY DENSITY (PCF) MOISTURE C0NTENT(%) -200 (%) m - 2 . 4 SM 0-4' Silty Sand, dark brown to black, moist to wet SM 4-8' Silty Sand, light brown, fine to . 6 medium grained sand, moist, medium dense 24 DR 102 20 •m . 8 •mm - 10 SM 8-16.5' Silty Sand, dark brown medium to fine sand, moist, medium dense 12 8-16.5' Silty Sand, dark brown medium to fine sand, moist, medium dense 38 DR 12 14 - 16 38 DR tf - 18 Boring Terminated (? 16.5' mm - 20 mm - m - 22 - mm - 24 - •m - 26 • 28 - mm PLATE. Testing Engineers-San Diego BORING LOG Prnji>rt.Palomar Airport Rd 2-11-87 gQ^j^g 5_ Type of Rig: B-fil Hole Diameter: Elevation:. Hammer Weight a Fnii- 140 ibs/30" Ground Water: JJ Logged Ry sec DEPTH(FT) SYMBOL Location: Sta: 63+50, 110' South of Centerline FIELD OESCRIPTION BLOWS/FT SAMPLE DRY DENSITY | (PCF) 1 MOISTURE CONTENT (%) 8 o o OJ 1 • 2 - /. SM 0-4' SILTY SAND, brown, with minor clay, moist • 6 ML-CL 4-10' CLAYEY SILT, dark brown, organic clay 32 DR 115 15 - 8 - 1 n CL 10-15' CLAY, brown, plastic, medium expansive potential, very stiff 23 DR • 12 • 14 • 16 SP 15-21.5' SAND, light brown, moderately - graded, medium dense - 18 - - 20 - 20 52 DR 107 19 1 22 Boring Terminated (3 21.5' - 24 - - 26 - - 28 - Testing Engineers-San Diego BORING LOG CM ON o pv Project: Palomar Airport Rd^u. 2-11-87 Type of Rig- B-61 Hole Diameter- 8 inches Hammer Weight a Fall: Boring No: .140 lbs/30" Ground Wnfer- None Elevation: _ - Logged By SCG a. UJ o >- cn Location: Sta: 50+00, 90' North of Center line FIELD DESCRIPTION t/> Q < tn fc CO — z u. tn o o o CNJ • 2 . 4 8 10 12 14 16 18 20 - 22 . 24 - 26 - 28 SP SM 0-27' Clayey Sand Tan to grey, moist, medium dense to dense - Increasing clay content - Very dense 35 58 50-6" DR DR DR 27-30' Clayey Silt, orange-tan, hard Boring Terminated I? 30' 5Q-5" 112 13 Testing Engineers-Son Diego TEST PIT LOG Project No: ^092 Ground Elevation: Project Name: Palomar Airport Rnad Jest Pit NO: L Date Excavated: ^'27-S7 Ground Water: Nnnp Location: Sta: 82+30, 90' South of Center line PENETROMETER (tsf) LAB TESTS Wc% -200% 2 H UJ )^ 4 H A - FILL 2,5-6.0 o. UJ a 8 H 10 B - FORilATIONAL 7.0 12 - 14 - UNIT DESCRIPTION Sandy Silt Tan-brown, variable clay content, moist, medium dense Sandy Clay Dark brown to black, moist, hard Testing Engineers-San Diego it TEST PIT LOG Prnierf Nn- ^092 p^^,^^^ ^^^^^ Palomar Airport Road D;* w« 2 am firniinri Flpvntion- Hnfp FYrnvntpH- l-27-b7 (^rniinH Vl/nfpr-None Location: STA - 82+00, 110' PENETROMETER LAB TESTS 0 -South of Centerline (tsf) Wc% -200% •m 'Ml 2 - UJ A - FILL u. *t • z X 6- a. UJ ° 8-B - FORMATIONAL >7.0 •M 10 - sm 12 - 14 - UNIT DESCRtPTlON m •m mt A Sandy Silt Tan-brown, variable clay, moist, medium dense mt B Sandy Clay Dark Brown to black, moist, hard •tm m •m *m PI iTF Tes//ng Engineers-San Diego TEST PIT LOG Project No: 7092 Project Name: Palomar Airport Rd. j^^^ Ground Elevation: ^-27-67 Qg^g Excavated: Ground Water: 0 - Location: Sta: 91+30, 80' South of Center line PENETROMETER (tsf) LAB TESTS Wc% -2007o A - TOPSOIL 2 - UJ ti! 4 • B - C - FORMATIONAL 4.5 - 6.0 UJ o D - FORMATIONAL 8 10 A E - FORMATIONAL 12 - 14 - UNIT DESCRIPTION D Sandy Clay Brown, medium to fine sand, organics, moist, soft to firm, 2 inches of asphaltic concrete $ 1.5' Clayey Sand White-tan, moist, medium dense Sandy Clay Dark brown with pockets of tan or red clayey sand, low expansion potential, moist, stiff to very stiff Silty Clay Black, some fine sand, some organics, moist stiff Clayey Sand Red-brown, moist, medium dense to dense PLATE Testing Engineers-San Diego TEST PIT LOG Prniprt Nn. 7092 Prn\(^H f\lnmp- Palomar Airport Road T«i Pi* Wn. 4 •m fimiinri FlPvntinn- DntP Firnvntprf- 1-27-87 Ground Water-None MM Location: STA - 100+00, 60' PENETROMETER LAB TESTS 0 South of Centerline (tsf) Wc% -200% mm A - TOPSOIL 2.5 - 3.5 — £ • UJ B - FORMATIONAL >7.0 ii! 4 • C - FORMATIONAL — z £ 6 • D - FORMATIONAL Nl a. UJ ° 8-E - FORMATIONAL 10 - mm 1 V 12 - "•™ 14 - UNIT DESCRIPTION 'V A Sandy Clay •M Brown, medium to fine sand, organics, moist. soft to firm B Clay Stone Black to green claystone, moist, hard -,• C Silty Sandstone •m D White, fine grained sand, cemented, hard Sandy Claystone Dark brown to black, fine sand, moist, hard • mm E Silty Sandstone Brown, moist, dense to very dense Testing Engineers-San Diego TEST PIT LOG NO: Project Ground Elevation: 7092 Project Nome: Palomar Airport Road ^^^^ p,^ Date Excovated: ^-27-8? Ground Water: None Location: Sta: 74+50, 100 ft. North of Center line 0 2 H PENETROMETER (tsf) LAB TESTS Wc% -200% A - TOPSOIL B - FORMATIONAL \ii 4 H C - FORMATIONAL 6 8 - 10 - 12 - 14 - D - FORMATIONAL UNIT DESCRIPTION >7.0 Sandy Clay Black, fine sand, with organics, moist, soft to firm Clay Stone Black, fine sand, moist, hard Silt Stone White to tan, little fine sand, dry, hard Sandstone White to tan, cemented, dry, hard with green and red striations PLATE Testing Engineers-San Diego TEST PIT LOG Project No: ^^^^ Ground Elevation: Project Name: Paiomar Airport Road j^^^ Pit NO: _! Date Excavated: Ground Water: ^^^^ 0 - Location: Sta: 36+00, 30' North of Center line PENETROMETER (tsf) LAB TESTS Wc% -200% A - FORMATIONAL 2 4 H B - FOR>iATIONAL X 6 H *— UJ ° 8H C - FORMATIONAL 10 - 12 - 14 - UNIT OESCRIPTION Conglomerate Red-brown sand matrix with cobbles to 4", medium grained sand, moist, very dense Clayey Sand White, well graded sand, moist, very dense Sandy Claystone Green to tan, coarse sand, hard P1.AT6 Testing Engineers-San Diego SYMBOLS AND TERMS USED ON BORING LOGS DRIVEN RING SAMPU DRIVEN BAG SAMPLE DISTURBED SAMPLER TYPES Shown in SAMPLE column) H SHELBY TUBE ROCK CORE X SPLIT SPOON NO RECOVERY TERMS DESCRIBING CONSISTENCY OR CONDITION COARSE GRAINED SOILS (major portion retamed on Na 200 sieve); Includes (1 ] clean gravels and sands, and (2) silty or ctoyey gravels and sands. Condition <n the following toble is bosed on our interpretotion of blow counts using a hammer as noted on the bormg tog. DESCRIPTIVE TERM Very loose Loose Medium-dense Dense Very dense SPT VALUES.N blows per 12 in. (After Terzaghi a Peck, 1968) 0 to 4 4 to 10 10 to 30 30 to 50 >50 FINE GRAINED SOILS (major portion passing No. 200 sieve): Includes (1) inorganic and organic silts and days, (2) grovelly, sandy, or silty cloys, and (3) cloyey silts. Consistency is roted occording to sheoring strength, as indicated by penetrometer readings or by unconfined compression tests. UNDRAINED DESCRIPTIVE TERM SHEAR STRENGTH KIPS/SO FT Vftfy soft Soft Rrm Stiff Vftry stiff Hord less than 0.25 0.25 to 0.50 0.50 to 1.00 1.00 to 2.00 2.00 to 4.00 4.00 and higher NOTE: Ftssured days may have lower unconfined compressive strengths than shown above, because of planes of ¥/eakness or crocks in the soii The consistency ratings of such soils are based on penetrometer readings. TERMS CHARACTERIZING SOIL STRUCTURE Fissured — containing shrinkage crocks, frequently filled with fine sand or silt, usually more or less vertical Interbedded — composed of olternote layers of different soil types Calcoreous — containing 12 to 50 percent colcium carbonote Carbonate — containing more than 50 percent calcium carbonate Well graded — hoving wide ronge in groin sizes and substantiol amounts of all intermediate particle sizes Poorly graded — predominotely of one grain size, or having a range of sizes with some mtermediote size missing Terms used in this report for describing soils according to their texture or gram size distribution ore in accordance with the UNIFIED SOIL CLASSIFICATION SYSTEM, as describedm Techmcat Memorandum Na.3-257; Waterways Exp.Sla,3/53 PLATE. GENERALIZED SUBSURFACE PROFILE 112i 102 92 :? 82^ w 72 52-1 I 42 LU TP6 TPS SILTY CLAY/ CLAYEY SAND TP4 SAND STONE FORMATIONAL) & CLAY-SILT 100 GENERAL NOTES Data concerning subsurface conditions have been obtained at boring location only. Actual conditions at locations between borings may differ from the profiles shown. HORIZONTAL SCALE hi2 102 h92 82 72 -62 52 42 m < fl) o 3 Testing Engineers-San Diego No: 7092 GENERALIZED SUBSURFACE PROFILE Dote: 3/2/87 14 Testing Engineers-San Diego UNIFIED SOIL CLASSIFICATION PLASTICITY CHART GROUP )YMBOL TYPICAL NAMES size) GW Well-graded gravels, gravel-sond mixtures, littte Of no fines 200 sieve GP Poorly graded grovets, grovel-sand mixtures, little or no fines SOILS lhan Na Silty. grovets, grovel- sond-silt mixtures jRAINED 1 is larger GC Clayey gravels, grovel sond-doy mixtures COARSE-( of material SW Well-groded sonds, gravelly sands, littte or no fines re thon half SP Poorly groded sands, gravelly sonds, little or no Hnes o 2 SM Silty sands, sand-silt mixture SC Cloyey sonds, sond- cloy mixtures GROUP SYMBOL TYPICAL NAMES )0 sieve) ML Inorganic silts ond very fine sands, rock flour silty or clayey fine sands, or cloyey silts with slight plostidty SOILS oiler than Na 2C CL Inorgonic days of low to medium plasticity, grovelly days, sondy days, silty cloys, leon clays -GRAINED leriol is sm OL. Orgonic silts ond orgonic silty cloys of low plosticity FINE an half of moi MH Inorganic silts, micaceous or diotomoceous fine sandy or silty soils, elastic silts More thi CH Inorgonic cloys of high plosticity, fot cloys OH Organic cloys of medium to high plosticity, organic silts Pt Peat and other highly orgonic soils NOTE: l)Gn)up symbol presented in SrweOL column on BORING LOC 2) The "A" line is on empirical relationship esloblished by A. Cosogronde. PLATE City of carlsbad Tnl^'nJ'lllV Palomar Airport Road Widening Job No. 7092 APPENDIX LABORATORY TEST DESCRIPTION LABORATORY TEST RESULTS City of carlsbad Tnl^'V'llTl palomar Airport Road Widening Job No. 7092 T.AT^nP^TQRY DESCRIPTION 1. MnTgTTTBE DENSITY TESTS The field moisture content and dry density tests were performed on ring drive samples retained during the field investigation. The field moisture content was determined as a percentage of the dry unit weight. 2. EXPANSION Expansion tests were performed on representative samples at existing condition of density and moisture content. The samples were air dried and allowed to swell against a surcharge load of 150 pounds per square foot. City of carlsbad Tnl^'V'lHV Palomar Airport Road widening ^ob No. 7092 LABORATORY RESULTS .... 1. Moisture Content And In-Place Densitv Tests Field Dry Field Moisture Sample No. and Depth BHl e 35 ft. Density (lbs. Content Sample No. and Depth BHl e 35 ft. t>er cubic foot) (percent) Sample No. and Depth BHl e 35 ft. 127.9 7.6 BH2 e 5 ft. 100.1 5.1 4* BH3 @ 5 ft. 113.8 15.2 rm BH3 e 10 ft. 114.4 14.8 nM BH4 @ 5 ft. 102.4 20.0 •— BH5 @ 10 ft. 114.6 14.9 BH5 @ 20 ft. 106.6 18.8 BH6 e 20 ft. 111.5 12.9 PLATE A-1 City of Carlsbad Palomar Airport Road Widening March 3, 1987 Job No. 7092 2. Expansion Test Sample No. and Depth TP3 e 3-4 ft. BH3 e 5 ft. BH5 @ 10 ft. BH6 e 10 ft. Expansion Index 32 62 65 7 Potential Expansion Low Medium Medium Very Low PLATE A-2