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Home My WebLink About; La Costa Village Apartments Lot 398; Soils Report Update of Preliminary; 1989-07-11- - - UPDATE REPORT OF THE PRELIMINARY SOILS - .- - - - - - INVESTIGATION REPORT Of La Costa Village Apartments (PCD-88) Lot 398, Map 6905 Luciemaga Street Carlsbad, Califomia - - ENGINEERING DEPT. Ll9RAfW City of Carlsbad 2075 Las Palmas Drive Carhbad CA92009-4859 b;-rEcElVED JUL 20 1989 ClTy OF CARLSBAD ~~~~ pan.:. Services - SAN MARCOS ENGINEERING, INC. civil l soils l foundations Job Number 89056 La Costa Village Apartments (PCD-88) Lot 398, Map 6905, Luciernaga Street, Carlsbad TABLE OF CONTENTS Item Description Description of Site Conclusions & Recommendations Limitation of Report Enclosures 3 5 10 11 - - - - - - - - 370 Mulberry Drive Suite E l San Marcos l CA - 92069 l (6I9)744-0111 Page 2 - SAN MARCOS ENGINEERING, INC. 370 MULBERRY DRIVE. SUITE E SAN MARCO5 CA 92069 - (619) 744-0111 Civil Engineering . Plannning l Land Developing l Surveying l Soils and Foundation Engineers .- July 11, 1989 Job No. 89056 - Mr. Hang C. Hsuieh P.O. BOX 8334 .- Ranch0 Santa Fe, CA 92067 -. - Re: La Costa Village Apartments (PCD-88) Lot 398, Map 6905 Luciernaga Street Carlsbad, CA Dear Mr. Hsuieh, As per your request, - submitted herewith is an update report of the Preliminary Soils Investigation of the - above referenced project site. - Description of Site .,.~. A field site visit was made on July 7, 1989 and the following observations are submitted: - - - Page 3 SAN MARCOS ENGINEERING, INC. civil l soils l foundations Job Number 89056 La Costa Village Apartments (PCD-88) Lot 398, Map 6905, Luciernaga Street, Carlsbad, California -. - 1. The project site is vacant at this time and it appears that no construction activity had taken place at the said - site since our soils investigation of the site in July, 1985. A copy of said preliminary soils investigation report is appended as Appendix D. - -. 2. No construction activities had taken place in the adjacent areas that may affect the proposed project at - said site. - - - - 3. Additional lab soils testing were performed of the prevailing site soils composed of Tannish Brown Silty to Sandy Clay with some broken gravel. Samples were taken at about 2 feet below existing grade approximately between B-4 and B-5 shown on Plate 2 of Appendix D. Test results are shown below: a. Direct Shear Tests (ASTM) Apparent Internal Friction Angle@ = 34.2' Apparent Cohesion C = 207 psf b. Expansion Index Tests (UBC Std 29-l) E.I. = 35, low potential expansion - - - 370 Mulbeny Drive Suite E l San Marcos l CA 9 92069 l (619)744-0111 Page 4 SAN MARCOS ENGINEERING, INC. civil l soils l foundations Job Number 89056 La Costa Village Apartments (PCD-88) Lot 398, Map 6905, Lucieruaga Street, Carlsbad, California C. Maximum Dry Density (Data taken from Appendix D) Maximum Dry Density = 117 pcf Optimum Moisture Content = 10.5% Copy of test results are appended as Appendix B. Soil Classification used in this report is based on the Unified Soils Classification System as indicated in Appendix C. - Conclusion and Recommendations - 1. It is our opinion that the site soil conditions have not changed and the findings and recommendations found in the - preliminary soils investigation shown in Appendix D are still valid. - .- - - 2. We recommend that the existing pad be cleared of all vegetation, organic matters and other deleterious materials and all unsuitable materials carted away from site. The existing site soils shall then be scarified to at least 12' deep, the soils moisture conditioned and recompacted to at least 90% of maximum dry density. The Earthwork Specification shown in Appendix A forms part of these recommendations. 3. The building structures are recommended to be founded with standard spread footings at an allowable soil - 370 Mulberry Drive Suite E l San Marcos l CA l 92069 l (619)744-0111 Page 5 SAN MARCOS ENGINEERING, INC. civil l soils l foundations Job Number 89056 .- La Costa Village Apartments (PCD-88) Lot 398, Map 6905, Luciernaga Street, Carlsbad, California - - - - - - - Subgrade - - bearing pressure of 1600 psf. Bottom of footings should be at least 24" below adjacent finish grade. Perimeter wall footings should be at least 18" wide and reinforced with 2-#5 bars placed 3" above bottom of footing and 2-#5 bars placed 2" below top of footing. Isolated footings should be at least 24" square and reinforced with 3-#5 bars placed each way. 4. Concrete slabs should be at least 4" thick and reinforced with 6x6-10/10 welded wire mesh placed at mid-height of slab. The slab shall be underlain by 4'thick sand with vapor barrier placed below the sand. The vapor barrier shall be placed over at least 1" thick of sand placed over the subgrade. The typical section is shown below: 6x6-10/10 welded wire mesh 4" concrete slab 4" sand vapor barrier 1" sand 370 Mulberry Drive Suite E l San Marcos l CA l 92069 l (619)744-0111 Page 6 - SAN MARCOS ENGINEERING, INC. civil 9 soils 9 foundations Job Number 89056 - Lu Costa Village Apartments (PCD-88) Lot 398, Map 6905, Luciernaga Street, Carlsbad, California - - Prior to placing the sand fill and the vapor barrier, the subgrade soils under the slab should be moistured to at least 3% above optimum moisture content. - - - - - - - - .- - - 5. We recommend that the footing trench soils be inspected by a soils engineer prior to pouring of concrete for the footings to ensure that the soils are stable and properly compacted. 6. Cut and fill slopes should have maximum slope ratio of 2 horizontal and 1 vertical. The outside of footings at slope areas should be at least 8' measured horizontally from the daylight line at the slope as shown below: Finish Grade Fill Slope I I I nr ,& r' !-1 1 1 Footing - - 370 Mulbeny Drive Suite E 9 San Marcos l CA - 92069 9 (619)744-0111 Page 7 - SAN MARCOS ENGINEERING, INC. civil l soils l foundations Job Number 89056 La Costa Village Apartments (PCD-88) Lot 398, Map 6905, Luciernaga Street, Carlsbad, California .~ - - - - - - - - - - - - - .- - I. For the design of the masonry retaining walls, the San Diego County Standard Drawings and Specifications for Retaining Walls can be used in the design and construction of the proposed walls. The following soil parameters can be used in the design of non-standard walls: Active pressure, equivalent fluid pressure, level backfill, = 30pcf Active pressure, equivalent fluid pressure, 2:l (horizontal to vertical ratio) backfill = 43pcf Passive Pressure, Equivalent fluid pressure, level backfill = 300pcf Coefficient of friction between soils and bottom of masonry = 0.4 Allowable Soil Bearing Pressure = 1600 psf 8. The structural section for the road and parking paving can be determined when the R-Value tests of the prepared subgrade soils have been taken. - 370 Mulberry Drive Suite E l San Marcos l CA l 92069 l (619)744-0111 Page 8 - SAN MARCOS ENGINEERING, INC. civil l soils 8 foundations Job Number 89056 La Costa Village Apartments (PCD-88) Lot 398, Map 6905, Luciemaga Street, Carlsbad, California - - - - 9. The foundation plans will need to be reviewed by this firm to make sure that the intent of these recommendations are followed. 10. All surface water runoff should be directed away from the foundation system positively. 11. If during grading operations, soils different from the soils described here in this report are found at the site, it is recommended that this firm be notified so that the proper evaluation and recommendations can be made. If you have any questions about this report, please call us. Continued - - .- 370 Mulberry Drive Suite E l San Marcos 9 CA l 92069 l (619)744-0111 Page 9 SAN MARCOS ENGINEERING, INC. civil l soils l foundations Job Number 89056 La Costa Village Apartments (PCD-88) Lot 398, Map 6905, Luciemaga Street, Car&bad, California - - - - Limitation of Report The opinions and recommendations presented in this report are based upon surficial and limited subsurface observations and logical projections inferred from observed conditions and the assumption that the soil conditions do not deviate appreciably from those encountered. Should conditions varying from those presented here in this report be encountered during the developmental construction, this firm should be notified right away so that a qualified soils engineer can inspect the site conditions and evaluate the potential effects and present recommendations. The report has been prepared in accordance with generally accepted standards of geotechnical engineering practice at the time of its preparation. No other warranties expressed or implied are made as to the professional consultation and - recommendations contained herein. This report is provided for the exclusive use of the client or his authorized agents. - Very truly yours, SAN MARCOS ENGINEERING, INC. - - - - 370 Mulberry Drive Suite E l San Marcos l CA l 92069 l (619)744-0111 Page 10 SAN MARCOS ENGINEERING, INC. civil l soils l foundations Job Number 89056 Lu Costa Village Apartments (PCD-88) Lot 398, Map 6905, Luciemaga Street, Carlsbad, California EncLosures: Appendix A. Recommended Earthwork Specifications Appendix B. Laboratory Soils Testing Results Appendix C. Unified Soils Classification System Appendix D. Preliminary Soils Investigation dated July 25, 1985 370 Mulberry Drive Suite E l San Marcos 8 CA l 92069 l (619)744-0111 Page 11 SAN MARCOS ENGINEERING, INC. civil l soils l foundations Job Number 89056 La Costa Vilhge Apartments (PCD-88) Lot 398, Map 6905, Luciemaga, Carlsbad, .- - - - - - - - - - APPENDIX A. RECOMMENDED EARTHWORK SPECIFICATIONS - 370 Mulberry Drive Suite E l San Marcos l CA l 92069 9 (619)744-0111 SAN MARCOS ENGINEERING, INC. civi: l soils 9 foundations APPENDIX A -RECOMMENDED EARTHWORK SPECIFICATIONS ,_ Job Number 89056 ,- _~. - - - - - 1. GENERAL DESCRIPTION. The objective is to obtain uniformity and adequate internal strength in filled ground by proven engineering procedures and tests so that the proposed structures may be safely supported. The procedures include clearing and grubbing, removal of existing structures, preparation of land to be tilled, processing the fill soils, filling of the land, and the spreading and compaction of the tilled areas to conform with the lines, grades, and slopes as shown on the approved plans. The owner shall retain a Civil Engineer qualified in Soil Mechanics (herein referred to as Engineer) to inspect and test the filled ground as placed to verity the uniformity of compaction of filled ground to the specified 90 percent of maximum dry density. The Engineer shall advise the owner and grading contractor immediately if any unsatisfactory conditions are observed to exist and shall have the authority to reject the compacted filed ground until necessary corrective measures are taken to comply with the specifications. It shall be the soil responsibility of the grading contraCtor to achieve the specified degree of compaction. 2. CLEARING, GRUBBING AND PREPARING AREAS TO BE FILLED. a. All bmsh, vegetation, and any biodegradable refuse shall be removed, piled and burned or otherwise disposed of as to leave the areas to be filled free of vegetation and debris. Any uncompacted filed ground or loose compressible natural ground shall be removed unless the report recommends otherwise. Any unstable, swampy, or otherwise unsuitable areas shall be corrected by draining or removal or both. b. The natural ground which is determined to be satisfactory for the support of the tilled ground shall then be plowed or scarified to a depth of at least six inches (6”). and until the surface is free from ruts, hummocks, or other uneven features which would tend to prevent uniform compaction by the equipment to be used. c. After the natural ground has been prepared, it shall then be brought to the proper moisture content and compacted to not less than 90 percent of maximum density in accordance with the A.S.T.M. D1557-78 method which uses 25 blows of a 10 pound rammer falling 18 inches on each of 5 layers in a 4- inch diameter l/30 cubic foot cylindrical mold. d. Where fills are made on hillsides or exposed slope areas, with gradients greater than 10 percent, horizontal benches shall be cut into firm undisturbed natural ground in order to provide both lateral and vertical stability. This is to provide a horizontal base so that each layer is placed and compacted on a horizontal plane. The initial bench at the toe of the fill shall be at least 10 feet in width on fii undisturbed natural ground at the elevation of the toe stake placed at the natural angle of repose or design slope. The Engineer shall determine the width and frequency of all succeeding benches which will vary with the soil conditions and the steepness of slope. - Lu Costa Village Apartments (PCD-88) Lot 398, Map 6905, Duciemaga St., Carlsbad 370 Mulberry Drive Suite E l San Marcos l CA l 92069 l (619)744-0111 - SAN MARCOS ENGINEERING, INC. civil 9 soils l foundations APPENDIX A -RECOMMENDED EARTHWORK SPECIFICATIONS ~,. Job Number 89056 3. MATERIALS AND SPECIAL REOUIREMENTS, The fill soils shall consist of select materials free from vegetable matter, and other deleterious substances, and shall not contain rocks or lumps greater than 6 inches in diameter. This may be obtained from the excavation of banks, borrow pits or any other approved sources and by mixing soils from one or more sources. If excessive vegetation, rocks, or soils with inadequate strength or other unacceptable physical characteristics are encountered, these shall be disposed of in waste areas as shown on the plans or as directed by the Engineer. If, during grading operations, soils are found which were not encountered and tested in the preliminary investigation, tests on these soils shall be performed to determine their physical characteristics. Any special treatment recommended in the preliminary or subsequent soil reports not covered herein shall become an addendum to these specifications. 4. PLACING. SPREADING. AND COMPACTING FILL MATERIALS. a. When the moisture content of the fill materials is below that specified by the engineer, water shall be added in the borrow pit until the moisture content is near optimum to assure uniform mixing and effective compaction. b. When the moisture content of the fill material is above that specified by the engineer, resulting in inadequate compaction or unstable fill, the fill material shall be aerated by blading and scarifying or other satisfactory methods until the moisture content is near optimum as specified. c. After processing, the suitable fill material shall be placed in layers which, when compacted, shall not exceed six inches (6”). Each layer shall be spread evenly and shall be thoroughly mixed during the spreading to ensure uniformity of material and moisture in each layer. d. After each layer has been placed, mixed and spread evenly, it shall be thoroughly compacted to not less than the density set forth in paragraph 2(c) above. Compaction shall be accomplished with sheepsfoot rollers, multiple-wheel pneumatic-tired rollers, or other approved types of compaction equipment, such as vibratory equipment that is specially designed for certain soil types. Rollers shall be of such design and maintained to such a level that they will be able to compact the fill material to the specified density. Tamping feet of sheepsfoot rollers shall be maintained such that the soils will be compacted rather than sheared by the roller. Rolling shall be accomplished while the fill material is at the specified moisture content. Rolling of each layer shall be continuous over its entire area and the roller shall make sufficient trips to insure that the specified density has been obtained. Rolling shall be accomplished in a planned procedure such that the entire area to be filled shall receive uniform compactive effort. e. The surfaces of the fill slopes shall be compacted by means of sheepsfoot rollers or other suitable equipment. compacting operations shall be continued until the slopes are stable and until there is no appreciable amount of loose soil on the slopes. Compacting of the slopes shall be accomplished by - La Costa Village Apartments (PCD-88) Lot 398, Map 6905, Ducienzaga SL, Carlsbad 370 Mulberry Drive Suite E 9 San Marcos 9 CA l 92069 l (619)744-0111 - SAN MARCOS ENGINEERING, INC. civil 9 soils 8 foundations APPENDIX A - RECOMMENDED EARTHWORK SPECIFICATIONS Job Number 89056 ,~~~ - - - - backrolling the slopes in increments of 3 to 5 feet in elevation gain or by other methods procuring satisfactory results. f. Field density tests shall be taken for approximately each foot in elevation gain after compaction, but not to exceed two feet in vertical height between tests. Field density tests may be taken at intervals of 6 inches in elevation gain if required by the Engineer. The location of the tests in plan shall be so spaced t give the best possible coverage and shall be taken no farther apart than 100 feet. Tests shall be taken on comer and terrace lots for each two feet in elevation gain. The Engineer may take additional tests as considered necessary to check on the uniformity of compaction. Where sheepsfoot rollers are used, the tests shall be taken in the compacted material below the disturbed surface. No additional layers of fdl shall be spread until the field density tests indicate that the specified density has been obtained. g. The till operation shall be continued in six inch (6”) compacted layers as specified above, until the till has been brought to the finished slopes and grades as shown on the accepted plans. 5. INSPECTION. Sufficient inspection by the Engineer shall be maintained during the filling and compacting operations so that he can verify that the till was constructed in accordance with the accepted specifications. 6. SEASONAL LIMITS. No fill materials shall be placed, spread, or rolled if weather conditions increase the moisture content above permissible limits. When the work is interrupted by rain, till operations shall not be resumed until field tests by the soils engineer indicate that the moisture content and density of fill are as previously specified. 7. LIMITING VALUES OF NONEXPANSIVE SOILS. Those soils that expand 3.0 percent or less from air dry to saturation under a unit load of 150 pounds per square foot are considered to be nonexpansive. 8. All recommendations presented in the attached report are a part of these specifications. -- Ln Costa Village Apartments (PCD-88) Lot 398, Map 6905, Duciernaga Sk, Carlsbad 370 Mulberry Drive Suite E l San Marcos l CA l 92069 9 (619)744-0111 - Natural Ground Surface I- Stripping Depth: Remove - -- -~ - Notes: 1. 2. 3. -- All Topsoil width W should be of least 10: The outside edge of the bottom key shall be below topsoil or loose surface material. Keys are required where the natural slope is steeper than 10 percent gradient or JO horizon tat to I veitical. TYPICAL KEY BENCHING FOR SLOPES No Scale - - SAN MARCOS ENGINEERING, INC. civil l soils l foundations Job Number 89056 Lu Costa Village Apartments (PCD-88) Lot 398, Map 6905, Luciernaga, Carlsbad, - - - - -. - - - - - - -. - - APPENDIX B. LABORATORY SOILS TESTING RESULTS - 370 Mulberry Drive Suite E l San Marcos l CA l 92069 l (619)744-0111 - .- - -. 1800 : / I , / j j M j / / 0 600 1200 1800 2400 3000 3600 Normal Stress, PM mi k.RHPLE NO. 1 2 3 ;..j_.:__ ..2..:_.j_.i._ 800 WATER CONTENT, i! 21.9 21.6 22.0 + DRY DENSITY, PC+ 104.4 104.4104.4 g ~fv~R~~6m~, % 0.5840.5840.584 99.4 97.8 99.8 I- DIAMETER, in 2.37 2.37 2.37 Q: HEIQHT, in 1.00 1.00 1.00 NORMFIL STRESS, ps.9 509 1017 1524 400 -0 0.1 0.2 0.3 0.4 Horiz. Deform., in ULT. SHEAR, psf SAMPLE DATA iAMPLE TYPE: REMOLDED CLIENT: HSUIEH IESCRIPTION: TAN TO YELLOWISH LT BRN SAND, <SW> TR CL OR MLPROJECT: PRELIMINARY SOILS INVESTIGATION .L= PLO PI= LUCIERNAGR STREET, CARLSBAD ;PECIFIC GRAVITY= 2.65 SAMPLE LOCATION: B-S 0 1.5 - 2 FT 1EMARKS: QUICK, UNCONSOLIDATED PROJ. NO.: 89056 DRTE: 7-X0-89 DIRECT SHERR TEST 'IO. NO. 1 ! I I 3 l% 3/I 3/e 100 !? s 00 Jt &i 70 gl 8 40 2 30 ii! 20 10 0 209 60 20 I I I I / I I I I I / 4 0 16 30 50 100 200 SIEVES DEBalIPrIvE lEIw \ \- __ btt -- lh 20 little 10 0 trace 2 0:6 0;2 0.06 0.62 0.006 0.002 GRAIN SIZE IN MILLIWll3l!3 BWIDEBS I I GR4VEL SANI C SILT. Non-Phtic. Ghesidess COBBLES C I M J F C J M 1 F CLAY-SOIL. Plasticity & Clay+abitiea 228 76.2 25.4 9.52 2.0 0.59 0.25 0.074 MM. 9 in. 3 in. 1 in. 3/0 in. Nos. 10 30 60 200 SIEVES 7z&e- d?c&zLf, / 6’ (RAIN SIZE ANALYSIS. I~IFIUTICN AKJ DESCllIFTICti Cf SOILS. - SAN MARCOS ENGINEERING, INC. civil l soils l foundations Job Number 89056 _ La Costa Village Apartments (PCD-88) Lot 398, Map 6905, Luciernaga, Carkbad, - APPENDIX C. UNIFIED SOILS CLASSIFICATION SYSTEM - - I- - , 370 Mulberry Drive Suite E l San Marcos l CA l 92069 l (619)744-0111 I - - - UNIFIED SOIL ClASSiFiCA l7ON SYSTEM COARSE CIWN~ saL.s UORE THAN 50% OF MrER,Iu IS L.mE.Q7HAN E0 =EE FlNE m.uNl3 .5m.s Maw THAN 50x la= MATERIAL IS i%MLER C-IAN gm smf MAJOR DI MSION (;wAEL AND whfiur SrxLs MCRE IHAN .wx et- COARSE Fmc- nm REVINED av#4smE cuxNm.4MLs (um w “0 FINES) / CRAEL mm m&s (APPREQMLE AAmJN~ w mm) l- GM al-r *Am.% GQ,4EL-.5AND Ear UIYNRES GC cum (xIkFL$ GmLEL .%ND .%. T !mluR~ CLEANSAND SW IKU-GRADED WD.l GRAKLLY WDS, (LlmE as ND FINES) LmLE w NO frN5. SP ma?LY-G?AL7ED SANLX GRAKLLY .%NL%s LnnE OR NO “MS SAhm lwm SM 9Li-r s.uk%i sA”D-SlLT uIxluREs flNES (APPRECYARLE AmJNT aF nNEs) SC cum WDS, SAND-cu Y MlxNREz lNoRwNlC SLE mm YERY “NE SANDS ML mxx FLCUR. 9i.l-i a? mm cars WlH SUGW PlAsllaTy. HIGHLY ORGANIC SYMBOL DESCRPllON GW KLL-m.wED GRAy9 CRAEL-SAW AmNREs “l7l.r OR NO “Ms Gp PDMKY-GWDEO Gwvzs oplrn SAND UlxluREs. urn lx NO “Mrs iED uAMT mAN5D lNoRc.wlC aA% OF LOW TO UEm”k4 CL PtAsllan: GwkELLY CLAEj SANDY CUE, SJUY CUB, LEAN MIS. OL mwlc SILTS ANo m!GANlC .?lLrr MYS OF LOW PLA*nam MH INmcANIc YLls Mlc.4cwws Lx DIIlwAcEws “NE SAN0 OR SLTY mu I I NOE: ~u.L.~B~c& INDICTA E B~QDERLWE .S(XL KEY ,To SAMPE DATA \ MOISTURE CONTENT. (2 OF DRY DENSITY) -I -DEPTH OR ELEVATION (FEET;) wh4PL.E RECOERY SAUPLER TYPE UNDISNRBED HD - 3 INCH SPLIT NBE SAMPLER. l-W - 3 INCH ThiN WALL SAMPLER SPT- 2 INCH SPLIT TUBE SAMPLER c- ROCK CORE B- BULK DISTRIBUED SAMPLE SAN MARCOS ENGINEERING UNlFlED SaL ctAsswcAll~ SyslEN AND KEY To SAMPLE DATA - SAN MARCOS ENGINEERING, INC. civil l soils l foundations Job Number 89056 La Costa Vilhge Apartments (PCD-88) Lot 398, Map 6905, Luciernaga, Carlsbad, APPENDIX D - PRELIMINARY SOILS INVESTIGATION DATED JULY 25, I985 - - 370 Mulberry Drive Suite E l San Marcos l CA l 92069 l (619)744-0111 - - SAN MARCOS ENGINEERING 380 MULBEFrhw DWVI, ,u,rs . *AN UIICOS, CA *2oe* - ldl0, 74..0,,, Civil Engineers l Planners l Land Development l Surveys l Sails and Foundation Engineering July 25, 1985 Mr. Ken Pierre b Mr. Jim Tung 432 Taylor Street Vista, CA 92083 Re: Lot 398 of La Costa Meadows, Unit #2 Map 6905, Carlabad, California proposed Apartment Prolect Dear Mr. Pierre and Mr. Tung, AS per your request, we have performed a preliminary soils investigation at the above referenced site for the proposed apartment prolect thereat and this report is presented ae regarda our opinion of the site aoils engineering factore that may affect your prolect. - - - - - - Description of Site ------ ---- -- ---- The above referenced proJect site ia located in Luciernage Street, Carlabad, California. The site ia a prepared graded Pad with the finish grading mildly sloping at about 1% approximately towards Luciernaga Street. Weeds and grass have grown at the site since it was graded. - - - - - - .- - - - - - SAN MARC09 ENGINEERING civil engineering, soils 6, foundation Pierre 6 Tung, Soils Report, Cont'd... Along the northerly and easterly property boundary lines are existing cut alopes with heights ranging from about 15 to 20 feet. At the top of the northerly cut are existing residential buildings and at the top of the easterly cut are apartment buildings. At the westerly boundary line is an existing fill slope. Plate 1 shows the Vicinity Map of the prolect site. Proposed ProlRgg --- ---- --- The proposed proJect is for the construction of 3 apartment building units. The structures will be 2-story, framed, and stucco buildinga with tile roof. No heavy loadings are anticipated. Purpose of the Preliminary Soils Investigation --_ ___ _- --- ----_----- ----- ----___ ----_ The purpose of this investigation is to determine the physical propertiee of the existing soila and to make a foundation recommendations. ELeli BxElnrafion The exploration program consist of site observation of existing soils at ground surface elevation and subsurface exploration. For subsurface exploration, a truck-mounted continuous flight auger was utilized to perform subsurface - 2 SAN MARCO3 ENGINEERING civil engineering, soil6 6 foundation - - - - - - - - Pierre 6 Tung, Soils Report, Cont'd... drilling. It was also equipped with a hammer to do standard penetration tests. California split samplers were utilized in sample procurement. Five (5) holes were drilled at site at the approximate locations shown in Plate 2. The depth of the holes varied from 6 to 15 feet. Soils encountered were carefully observed, classified and logged under the direction and supervision of a soils engineer. Bulk soils samples were alSO brought to the laboratory for further analysis and tests. Soils classification of the soils encountered were made according to The Unified Soils Classification System. Appendix E shows the Unified Soils Classification System. Finding= ------ Surface and near surface soils appear to be stable. There are no signs of soils movement. No soil tension cracks were detected. Some minor erosion rills were observed at the slopes and no signs of landslides were detected in the slopes. togs of the aoils encountered are shown in Plates 3 to 7, inclusive. A generalized soils profile of the subsurface soils which can be inferred from the soile logs indicate a generally uniform soils stratification and can be described a6 about 4 to 6 inches of topsoil with roots, weeds and mother vegetation matter, overlying about 10 feet of light . - - -- - - -. - - - _. - - - SAN HARCOS ENGINEERING civil engineering, soils & foundation Pierre 6 Tung, Soils Report, Cont'd... Brown to Tan to Yellowish Brown Silty to Sandy Clay with some broken fine gravel. The standard penetration blow counts were observed to range from 17 to 37 blows per foot indicating the soils consistency to be medium compact to compact soils. Below this stratum is Brown to Dark Brown Moist Sandy Clay and some fine gravel. This stratum appear to be the natural ground surface underlying the fill material of the prepared pad. Three (3) field compaction tests were performed at the site, taken at about a depth of 8" below the existing finish grade. The results are shown in Plates 8 to 10, inclusive, which indicate the soils to be compact to medium compact in the upper foot of the soils stratification. Laboratory Soils Teatinq --------- ----- ------ Four (4) maximum dry density tests were performed in four soil aamplea and the results are summarized below: Sample # Taken from Soil Max. Dry Optimum Moisture VP=+ Density Content (*) (pcf) 1 B-l at 8' 1 113.8 12.5 2 B-l at 2' 2 114.5 10.5 3 B-4 at 5' 3 117.0 10.5 4 B-l at 5' 2 115.5 12.0 - SAN MARCO3 ENGINEERING civil engineering, soils 6 foundation - - - - - - .- - - Pierre E. Tung, Soils Report, Cont'd... *Soil Type: 1. light Brown to Tan Silty to Sandy Clay, Traces of fine Gravel 2. Tan to Yellowish light Brown Silty to Sandy Clay, Some fine Gravel 3. Dark Brown Sandy Clay, Traces of fine Gravel Conclusion and Foundation Recommendations ---------- --- ---------- --------------- 1. In our opinion, the proIect site soils is stable for the construction of the proposed apartment prolect building. The following recommendations, however, need to be observed during the design and construction of the foundation systems of the structures. 2. The top 12" of the existing pad soils need to be scarified and all organic matters and other deleterious materials be removed. It shall then be watered and recompacted to at least 90% relative density prior to placing any fill material above it or the construction of footings upon it. The Earthwork Specifications shown in Appendix E forms part of these recommendations. 3. We recommend that the building structures be founded with standard spread footings at an allowable soil - - 5 - SAN MARCOS ENGINEERING civil engineering, eoils 6, foundation - - - - - - Pierre 8 Tung, Soils Report, Cont'd... bearing pressure of 1600 psf. Bottom of footings should be founded to at least 24" ad]acent below finish grade. Perimeter wall footings should be at least 18" wide and continuously reinforced with 2-#5 bars placed 3" above bottom of footing and 2-#5 bara placed 2" below top of footing stem or floor level. Isolated footings should be at least 24" square and reinforced with 3-#5 bars placed each way. 4. Concrete slabs should be at least 4" thick and reinforced with 6 x 6-lo/10 welded wire mesh placed at mid-height of slab. The slab shall be underlain by 4” thick sand with vapor barrier placed below the sand. The vapor barrier shall be placed over at least 1" thick of sand placed over the subgrade. The typical section is shown below: 6 x 6-14110 welded wire mesh 4" concrete slab 'd ,. 1" sand--/ . . 1 Y 0 . . k subgrade 6 .a , .O l *. ‘0 ..: - SAN MARCO3 ENGINEERING civil engineering, soils 6 foundation - - - - - - - - .- - - - - - Pierre 6 Tung Project, Soils Report, Cont'd... Prior to placing the sand fill and the vapor barrier, the subgrade soils under the slab should be moistured to at least 3X above optimum moisture content. 5. We recommend that the footing trench soils be inspected by a soils engineer prior to pouring of concrete for the footings to ensure that the soils are stable and properly compacted. 6. Cut and fill slopes should have maximum slope ratio of 2 horizontal and 1 vertical. The outside of footings at slope areas should be at least 8' measured horizontally from the daylight line at the slope as shown below: [Finish Grade No 3~81s - - SAN MARCOS ENGINEERING civil engineering, soils 6 foundation - - - - - - - Pierre 6 Tung, Soils Report, Cont'd... 7. For the design of the masonry retaining walls, The San Diego County Standard Drawings and Specifications for Retaining Walls can be used in the design and construction of the proposed walls. 8. The structural section for the road and parking paving can be determined when the R-value tests of the prepared subgrade soils have been taken. 9. All surface water runoff should be directed away from the foundation system positively. 14. If during grading operations, soils different from the soils described here in this report are found at the site, it is recommended that this firm be notified so that the propoer evaluation and recommendations can be made. If you have any questions about this report, please call us. Very truly yours, SAN MARCOS ENGINEERING BY Distribution: (4) Addressee 8 - - ..- - .~ - - .- SAN MARCOS ENGINEERING PLATE 1, ClVlC EwaNEC... SOIL. * P.au*o.l.o~ PROJECT: NORTH 1 NO SCALE I VICINITY~MAP LOT 398 APARTMENTS LA COSTA MDWS, #2 LUCIERNAGA STREET CARLSBAD, CA, REFERENCE: THOMAS BROS, MAP PAGE 20 c-4 q-n U.,, -_-- -- .._ - - - SAN MARCOS ENGINEERING CWlL ENGINEERS. *OILS * FO”NDA.TION - FILL SLOPE - - -. - PLATE 2. BORING LOCATION PLAN PROJECT: LOT 398 LA COSTA MDWS, UNIT NO, 2 APARTMENTS v \i+j/ '1 .--A-J+- 9 B-3 D-3 0 B-2 D-2 CUT SLOP r LUCIERNAGA 3TY I I - aeo h4”LmEII.Y DWVC. ,)U<rr I - SAN MARCOS ENGINEERING PLATE 3, BORING LOG CWlL ENOINL..,. 901LS a FO"f.D.naN Boring No. B-/ 380 M”L..“m* omwc ,“A--. llcl “ArnCO.. c. ,10.* 4dlOl ‘7.4.0111 Sheet N&/of/ - L uck07a9a CONTRACT NO. J PURPOSE Material & Remarks - - - .- - - SAN MARCOS ENGINEERING PLATE 4, BORING LOG C+,C E*OINEE.s. SOILS a FO"*D.TION 380 U"L.EIIS" 09i"C. ,cc-c . &ring No. B-2 SAM “.mC3*. c. *10*. ,dlOl 74d.0111 Sheet No.jof/ L uckr..a* CONTRACT ~0. J PURPOSE IBlowsl stows cm I Samole I I -- Depth Log Material 6 Remarks , n I .A-u-s;hde--w~ I - .- - - SAN MARCOS ENGINEERING ClYlL ENOINEE... s.OlLl a Fc.UNo.TlOn PLATE 5, BORING LOG 3eo MULBEW?" DIIWC. 5Ul7I m Boring No. 63 5AH LIII1C.2,. CA etos, 16191 744.0111 Sheet No.-&fL ,-NITmACT .*r. U -. .:,,.,r bcn” I nnCI I NV. r”t-iYU*C Blows Blows on Elev. on Spoon for 6” Sample 0 Casing Penetration N0. &I Material (L. Remarks Depth \ I w ’ / “. (r . . SAN MARCOS ENGINEERING PLATE 6, BORING LOG - - ,- - - - - 3-o ULLrnLRrl” 091”s. ,u,-*. Boring No. B-4 5.n Y.I)CJS. c. *ace. ,6,01 744-o,,, Sheet No./of / L uc&-fla+7 ORIN 2 S FOR - f&y Bh&h&uRLZ CONTRACT NO. J P&POSE Material 6 Remarks - - , , /o /o I I -- I I I I TV I I /‘6’ I I I I I -- - - - - - ,- - - - - - - - - - - SAN MARCOS ENGINEERING Cl”lL ENGINELm*. 501LI * FOw.D.IIOI( 380 UYLaEIIII” 0.8”s~ ,Li-l . s.* “.rnC?S. c. 910e. ldlO1 PLATE 7, BORING LOG Boring No. “-7 Sheet No./of- L uckrda+f ORIN 2 S FOR - /3p ~&&~&~#Z CONTRACT NO. J PUkPOSE Warerial 6 Remarks - - - - - .- - ,- - - PLATE 8, FIELD COMPACTION TEST .~~. SAN MARCGS ENGINEERING Civil Engineers, Soils & Foundation Date 5/#/gr * REPORT OF SOUS COMPACTION TEST Project & .4ddress P /Ii?/-Ez -Ji.579 Location of Test L /w&mqct, J ’ Height of Fill Test No. D-/ &/& Depth of Test Below F.G. gff 1. Bulk Density of Test Sand, WI = m27 PCf 2. Weight of Soil Taken From Test Hole, W2 = q%?/ Ibs. / gms. 3. Moisture Content of Soil, Calculated = 6.3 % 4. Dry Weight of Soil From Test Hole. W3 = 0.2205 W2/ (100 + WI= 6*oflc Ibs. 5. Weight of Sand Used in Test, Wq = \bs.’ 39’ gm. 6. Weight of Sand in Funnel, W5 = lbs.= /@z gm. 7. Volume of Test Hole, V = (W, - W,)/ 453. 6xW1 = &y3?3 ft3 0. Dry Density of Soil Tested, Wd = W3/ V = pp. Q/ pcf 9. Maximum Dry Density of Soil From Lab Tests, Wd max = //@S pcf .4t 0. M. C. F7-r % 10. Relative Compaction % = Wd / Wd may x 100 = $? “1. Remarks: Soil Type : h&!ka 52~~ J+ a%, &L-q& I Sketch of Test Location: (No Scale) Other Comments: 380 Mulberry Drive San Marcos, Ca. 92069 744-0111 Prepared By: * Per ASTM Dl556. Sand Cone v&h-I .- SAN MARCOS ENGINEERING Civil Engineers, Soils & Foundation PLATE 9, FIELD COMPACTION TEST Date s//y/f< - * REPORT OF SOILS COMPACTION TEST Project & -4ddress P’ 7zw& ‘W/e - 1. Arc 35lp - Location of Test ~~C/Lrr#~KZ- Test No. o-2 Height of Fill n/, 2&m/& Depth of Test Below F.G. 1. - 2. 3. - 4. - 5. 6. 7. a. 9. - - Bulk Density of Test Sand, WI = d7 70 PCf Weight of Soil Taken From Test Hole, W2 = &=a3 lbs./ gms. Moisture Content of Soil, Calculated = % 7s Dry Weight of Soil From Test Hole, W3 = 0.2205 W2/ (100 + w)= 57479 lbs. Weight of Sand Used in Test, W4 = I&,= 3357 gm. Weight of Sand in Funnel, W5 = lbs.= /3$7 fzm. Volume of Test Hole, V = (W, - W,)/ 453.6xWL = d&G?9 ft3 Dry Density of Soil Tested, Wd = W3/ V = AT* w PCf Maximum Dry Density of Soil From Lab Tests, Wd max = //cf. r pcf At O.M.C. /da r yT* 10. Relative Compaction % = Wd / Wd max x 100 = FT % Remarks: Soil Type : Sketch of Test Location: (No Scale) Other Comments: 300 Mulberry Drive San Marcos. Ca. 92069 744-0111 Prepared By: * Per ASTM Dl556. Sand Cone Method - SAN MARCOS ENGINEERING PLATE 10, FIELD COMPACTION TEST - Civil Engineers, Soils & Foundation Date s/#$?c - * REPORT OF SOILS COMPACTION TEST Project & -4ddress -7zYl.q &wf. 0 3?8 L J ’ Location of Test M c/b07agd, Test No. a-3 J Height of Fill Depth of Test Below F.G. f&/ 1. - 2. 3. 4. - 5. 6. .- 7. 0. 9. - Bulk Density of Test Sand, W1 = & 27 PCf Weight of Soil Taken From Test Hole, W2 = 33-3 lbs./ gms. Moisture Content of Soil, Calculated = 7.6 % Dry Weight of Soil From Test Hole, W3 = 0.2205 W,/ (100 + wl=G25/47 lbs. Weight of Sand Used in Test, W4 = Ibs.=%/S gmr Weight of Sand in Funnel, W5 = lbs.= ./&L gm. Volume of Test Hole, V = (W, - W,)/ 453.6xWI = f9Gy97 ft3 Dry Density of Soil Tested, Wd = W31 V = 8-3 94 pcf Maximum Dry Density of Soil From Lab Tests, Wd max = /Y&r- pcf At0.M.C. /‘@-s % 10. Relative Compaction % = Wd 1 Wd max x IO0 = 77 % Remarks: Soil Type : Sketch of Test Location: (No Scale) Other Comments: 300 Mulberry Drive San Marcos. Ca. 92069 744-0111 Prepared By: * Per ASTM Dl556, Sand Cone Method - SAN MARCOS ENGINEERING PLATE 11. I AR lJF\SITY TFST Cnll. e.arri*... ,QIU . ~O”IO.I~O” Moisture vs. Dry Density Curve sO&‘gy -*/ .5;/A A- 9& &%+7, z&e* @wd 140 130 120 110 100 90 MOISTURE CONTENT, ‘$6 Remarks: Test as per A.S.T.M. Designation D 1557-78 Method OA OB OC !JD aa0 UUL.*‘.” O.l”Z. ..,..s . a.* “..CC,. c. ,10.. #0,8,71..0111 - - - SAN MARCOS ENGlNEERlNG Clrll. L”O,,.#I... ,OlU . COV”D.IIO.4 PmE 12, LAB DENSITY TEST hloisture vs. Dry Density Curve &A s”2e,T,: -g/ ‘z $k-4i%M/k4 & & Lace tion: 5/A &.- s-Q% a&f uc/m*,wB# SdL f=e 5?-de-L - 140 130 5 a 120 . i E a 110 * a” 100 90 MOISTURE CONTENT, % Remarks: Test as per A.S.T.M. Deslqnation D 1557-78 Method OA q B OC fJD ,a0 U”L.I.CI D.l”*. .-.1x . a.* “..CCI. c. .,o.. calm, Irr.Olls PLATE 13, LAB DENSITY TEST - SAN MARCO5 ENGINEERING C,",l. LmOIms*.*. ,aLa . ro"..O.IlOn hloisture vs. Dry Density Curve Prqjectr /iire - 7zkq GR7db/kw /& 3'B:'~ LA& ' Location: hC/hzq~& -5' &w/I c5sz&& zzcec f-7-e' r&-;t / 140 130 8 !l( 120 . c z : 110 > 2 100 12 0 4 8 16 20 24 MOISTURE CONTENT, % Remarks: Test as per A.S.T.M. Desiqnation D 1557-78 Method OA q B q C OD sea UYL.E.- q .W‘. ‘....S . UI “..CCl. 5. *x0.. saao, ,...a,,, &m-w7 - .- - SAN MARCOS ENGINEERING PLATE 14, LAB DENSITY TEST Moisture vs. Dry Density Curve zz* /goA .@3sB ' I Location: AfC/+7~~Q, L2ckAG/ 130 6 a120 . :: ii 2 9110 > 2 - - 100 MOISTURE CONTENT, % Ren-arks: Test as per A.S.T.M. Designation D 1557-70 Method q A q B OC OD se0 ..lYL.I.mT E.P.‘. .r..v . UI “r*Ccs. c. .10.. <e*o, 7.r.011, -3 - SAN HARCOS ENGINEERING Civil Engineera, Soils b Foundation APPENDIX A RECOKUENDED EARTHWORK SPECIFICATIONS 1. QgHEfiAg, Qg~~g~pTgQ& The oblective is to obtain uniformity 6 adequate internal strength in filled ground by proven engineering procedures and teats a0 that the proposed structures may be safely supported. The procedures include the clearing and grubbing, removal of existing structures, preparation of land to be filled, processing the fill soile, filling of the land, and the spreading and compaction of the filled areao to conform with the lines, grades, and slopes as shown on the approved plans. The owner shall retain a Civil Engineer qualified in Soil Kechanics (herein referred to as Engineer) to inspect and test the filled ground as placed to verify the uniformity of compaction of filled ground to the specified 90 percent of maximum dry density. The Engineer shall advise the owner and grading contractor immediately if any unsatisfactory conditions are observed to exist and shall have the authority to reject the compacted filled ground until such that as corrective measures are taken, neceaaary to comply with the specifications. It shall be the sole responsibility of the grading contractor to achieve the specified degree of compaction. 2. CHHARINCL cizQe!mQ, ANQ ~REEARINC AREfd TQ Be eE!&PPz (a) All brush, vegetation, and any biodegradable refuse shall be removed, piled, and burned or otherwise disposed of as to leave the areas to be filled free of vegetation and debris. Any unconpacted filled ground or loose compressible natursl ground, shall be removed unless the report recommends otherwise. Any unstable, -=mv. or otherwise unsuitable areae shall be corrected by draining or removal, or both. (b> The natural ground which is determined to be satisfactory for the support of the filled ground shall then be ploved or scarified to a depth of at least eix inches (6"). and until the surface if free from ruts, hummocks, or other uneven features which would tend to prevent uniform compaction by the equipment to be used. 1 APPENDIX A, RBCOMNENDOD KARTNWORK SPICIFICATIOWI, CONT’D,.. - -,~ 3 - (C!) After the natural ground has been prepared, it ahall then be brought to the proper aofature content and compacted to not lees than 90 percent of IGACiSlUR deneity in accordance with the A.S.T.M. D1557-70 method which uaea 25 blowe of a 10 pound rammer falling 18 inchee on each of 5 layers in a 4-inch diameter l/30 cubic foot cylindrical meld. (d) Where fills are made on hillaider or exposed alope areas, with gradients greater than 10 percent, horizontal benchea shall be cut into firm undisturbed natural ground in order to provide both lateral and vertical stability. This is to provide a horizontal base so that each layer is placed and compacted~ on a horizontal plane. The initial bench at the toe of the fill ahall be at leaat 10 feet in width on firm undisturbed natural angle of repose or design alope. The Engineer ahall deteruine the width and frequency of all succeeding bencher which will vary with the aoil conditiona and the eteepnesa of alope. 3. n!Emu4P A&P' SPkmd4 llmeerelrer The fill aoil shall consist of eelect materials free from vegetable matter, and other deleterious subatancea, and ahall not contain rocka or lunpe greater than 6 inches in diameter. This nay be obtained from the excavation of banka, borrow pita or any other approved sourcea and by mixing eoila fro8 one or more eources. If excessive vegetation, rocks. or aoila with inadequate strength or other unacceptable phyeical characteristica ate encountered, theae ahall be diapoaed of in waste area.% aa ahown on the plane or as directed by the Engineer. If. during grading operatione. .aoile are found which were not encountered and teated in the preliminary investigation, teats on these soil8 ehall be performed to determine their physical characteristica. Any special treatment recommended in the preliminary or eubeequent soil reports not covered herein shall become an addendum to these specifications. 4. ELdEZNEr SP!?Ef!DZ!!GL Am Eo!?!mTm EI44 !?ATKRId4S, (a) When the moisture content of the fill material ia below that specified by the Engineer, water shall be added in the borrow pit until the moisture content is near optimur to assure uniform mixing and effective compaction. (b) When the moisture content of the fill naterlal ie above that specified by the Engineer, resulting in 2 APPENDIX A, RECOUKENDED EARTHWORK SPECIFICATIONS. CONT'D... -1.3 ,~..” -~ 1 ,.J inadequate compaction or unatable fill, the fill material ahall be aerated by blading and scarifying or other satisfactory nethoda until the moisture content is near optimur aa specified. (c) After processing. the suitable fill material shall be placed in layer6 which, when compacted, shall not exceed SiX inches (6".) Each layer shall be spread evenly and shall be throughly mixed during the spreading to ensure uniformity of material and moisture in each layer. (d) After each layer hae been placed, mixed and spread evenly, it ahall be throughly compacted to not leas that the denaity set forth in paragraph 2(c) above. Compaction ahall be acconpliehed with aheepsfoot rollere, multiple-wheel pneumatic-tired rollers. or other approved types of compaction equipment, such as vibratory equipment that ie specially designed for certain soil typea. Rollera shall be of such design and maintained to such a level that they will be able to compact the fill material to the specified density. Tamping feet of sheepefoot fellers shall be maintained such that the SOil will be compacted rather than aheared by the roller. Rolling shall be accompliehed while the fill material ia at the specified moisture content. Rolling of each layer shall be continuous over its entire area and the roller shall make sufficient trips to insure that the specified density has been obtained. Rolling shall be accompliehed in a planned procedure such that the entire areae to be filled shall receive uniform compactive effort. (e> The surfaces of the fill a1ope.a shall be compacted by means of sheepafoot rollers or other suitable equipment. Compacting operations shall be continured until the slopes are stable and until there is no appreciable amount of loose soil on the slopes.. Compacting of the slopee ahall be accomplished by backrolling the alopea in incrementa of 3 to 5 feet in elevation gain or by other method6 producing satisfactory reeulte. (f) Field density teats shall be taken for approximately each foot in elevation gain after compaction, but not to exceed two feet in vertical height between teats. Field density teats may be taken at intervala of 6 inches in elevation gain if required by the Engineer. The location of the teate in plan shall be so spaced to give the beat poesible coverage and ahall be taken no farther apart than 100 feet. Tests shall be taken on corner and terrace lot.5 for each two feet in elevation gain. The Engineer may take 3 - APPENDIX A, RKCOUKENDED EARTHWORK SPECIFICATIONS, CONT'li... additional testa ae considered neceeaary to check on the uniformity of compaction. Where sheepsfoot rollera are used, the teeta ahall be taken in the compacted material below the dieturbed surface. No additional layer6 of fill shall be spread until the field density tests indicate that the specified density has been obtained. (CT) The fill operation shall be continured in six inch (6") compacted layer6 aa specified above, until the fill hae been brought to the finfahed alopea and grades as shown on the accepted plans. 5. &spectlonL Sufficient inspection by the Engineer shall be maintained during the filling and compacting operations so that be can verify that the fill war constructed in accordance with the accepted apecificationr. 6. Seaaona& Lfm#~, No fill material ahall be placed, ------- --a spread, or rolled if weather conditiona increaee the moisture content above permiesible limits. When the work la interrupted by rain, fill operation6 shall not be reeumed until field teats by the eoilr engineer indicate that the moieture content and density of fill are ae previouely specified. 7. Lini$ina VsU*s of NmraPNnslYs aal., Those eoila that expand 3.0 percent or leaa fro8 air dry to saturation under a unit load of 150 pounds per square foot are conaideted to be nonexpansive. 8. All recommendationa presented in the attached report are a part of these epecificatione. - 4