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HomeMy WebLinkAbout; El Camino Estates; Soils Report; 1982-08-18SEOTECHNICAL INVESTIGATION EL CAMMl ESTATES EL CAHINO REM CMLSBALl, CALIFORNIA PREPARED FOR: Mr. Art Anderson 3445 Don Diablo Drive Carlsbad, California 92008 PREPARED BY: Southern Callfornia Soil 6 Testing, Inc. Post Office Box 20627 6280 Riverdale Street San Diego, California 92120 August 18, 1982 Mr. Art Anderson 3445 Don Diablo Drive Carlsbad, California 92008 SCS&T 14067 Report No. 1 SUBJECT: Report of Geotechnical Investigation, El Camino Estates, El Camino Real, Carlsbad, California. Gentlemen: In accordance with your request, we have completed a geotechnical inves- tigation for the proposed project. We are presenting herewith our find- ings and recommendations. The findings of this study indicate that the site is suitable for the proposed development provided the special site preparation recommendations presented in the attached report are complied with. If you have any questions after reviewing the findings and recommendations contained in the attached report, please do not hesitate to contact this office. This opportunity to be of professional service is sincerely appreciated. Respectfully submitted, SOUTHERN CALIFORNIA SOIL & TESTING INC. A&A, Curtis R. Burdett, C.E.G. #lo90 RRR:CRB:mw cc: (6) Submitted (1) SCS&T;Escondido SOUTHERN CALIFORNIA SOIL AND TESTING. I N I:. TABLE OF CORTEKTS PAGE Introduction and Project Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Project Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Findings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Site Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 General Geology and Subsurface Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Geologic Setting and Soil Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Unnamed Quaternary Sandstone (Qu) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Quaternary Alluvium (Qal) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Artificial Fill (Qaf) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Tectonic Setting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Geologic Hazards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Recommendations and Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . ..*............ 5 Site Preparation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Subdrains . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Earthwork . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..*............ 6 Foundations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Lateral Resistance . . . . . . . . . . . . . . . . . . . . . . . . ..'.................... 6 Figure No. 1, Typical Canyon Subdrain Detail . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Settlement Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Expansive Soils . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Slope Stability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Earthwork Shrinkage and Subsidence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Limitations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Review, Observation and Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . '9 Uniformity of Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Change in Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Time Limitations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Professional Standard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Client's Responsibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Field Explorations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ’ 11 Laboratory Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 ATTACHMENTS PLATES Plate 1 Plot Plans Plate 2 Unified Soil Classification Chart Plate 3-6 Trench Logs Plates 7 Direct Shear Test Results Maximum Density and Optimum Moisture Content Expansion Test Results APPEfQIX Recomnended Grading Specifications and Special Provisions -1 GEOTECHNI CAL INVESTIGATION EL CAJUN0 ESTATES EL CAMINO REAL CARLSBAD, CALIFORNIA INlROUUCTION ANU PROJECT DESfRIPTION This report presents the results of our geotechnical investigation for a proposed condominium mobile home park which is to be located on El Camino Real approximately 1500 feet south of Kelly Drive in the City of Carlsbad, California. It is our understanding that twenty mobile home spaces with associated street improvements are planned for this site. It is our understanding that a substantial amount of grading will be necessary to develop the site and that maximum cut and fill slopes planned are in the order of 20 to 25 feet in height. This information was taken from the preliminary grading plan prepared by the J. H. Edwards Company. The site configuration and exploration locations are shown on Plate Number 1 of this report. PROJECT SCOPE This investigation consisted of: surface reconnaissance; subsurface explo- rations; obtaining representative disturbed and undisturbed samples, laboratory testing; analysis of the field and laboratory data; research of SOUTHERN CALIFORNIA SOIL AND TESTING. I N c. SCS&T 14067 August 18, 1982 Page 2 available geological literature pertaining to the site; and preparation of this report. Specifically, the intent of this study is to: a) b) cl d) e) f) Explore the subsurface conditions to the depths influenced by the proposed construction. Evaluate, by laboratory tests, the pertinent engineering propert- ies of the various strata which will influence the development, including their expansive characteristics and settlement poten- tial. Define the general geology at the site including possible geolo- gic hazards which could have an effect on the site development. Develop soil engineering criteria for site grading and provide design information regarding the stability of cut and fill slopes. Determine potential construction difficulties and provide recom- mendations concerning these problems. Recommend an appropriate foundation system for the type of struc- tures anticipated and develop soil engineering design criteria for the recommended foundation design. FIIOIWGS SITE DESQUPTIOH The project site is a nearly rectangular shaped parcel of land, approxi- mately 3.0 acres in area, that is located adjacent to and south of El Camino Real in the City of Carlsbad, California. The site is bounded on SDUTHERN CALLIFORNIA SOIL AND TESTINO. I N c. SCS&T 14067 August 18, 1982 Page 3 the east and south by residential property and on the west by agricultural land. The morphology of the site is characterized by a relatively flat terrace area in the east-central and southern portions of the site with gentle to moderately steep slopes leading down to the drainage courses on the eastern and northern portions of the site. Elevations range from ‘approximately 60 feet to 105 feet (MSLD). Drainage is accomplished by sheetflow and in the previously mentioned drainage courses. The site is currently being used for agricultural purposes and most of the site is covered with a moderate growth of flowers; portions of the site are fallow and have been allowed to become overgrown with weeds and grasses. No structures currently occupy the site but an existing 8-inch water line for the City of Carlsbad traverses the site in a general northeasterly direc- tion. GENERAL 6EOLO6Y ANU SUBSURFACE COWITIONS 6EOLO6IC SETlIN6 ANU SOIL DESCRIPTION: The project site is located in the Coastai Plains Physiographic Province of San Diego County and is underlain by sedimentary deposits of Quaternary age and arti,ficial fill. A brief description of each of the materials encountered during our investigation is presented below. 1) UNNAMED QUATERNARY SANOSTONE (Qu): The oldest material exposed at the site are the reddish brown to greenish brown, medium dense to dense, fine to medium grained sandstones of Pleistocene age which are predominantly terrace deposits. These materials con- sist of sitly sands, clayey sands, and sandy silts and underlie the majority of the site. This unit is unconformably underlain at an undetermined depth by the Eocene-age sediments in the area. 2) QUATERNllRY ALLUVIUM (Qal): Alluvial and colluvial deposits of Holocene age were encountered in the lower areas in the south- eastern and northwestern portions of the site. These deposits consist of dark brown to dark gray, stiff to very stiff clays and clayey San%. SOUTHERN CALIFORNIA 9 0 I L AND TEOTINO. 1 N c. SCS&T 14067 August 18, 1982 Page 4 3) ARTIFICIAL FILL (Qaf): Man-made fills were encountered overlying portions of the alluvial deposits at the site. The fill encoun- tered near the southeastern corner of the site consists of brown silty clay and contains an abundance of deleterious material. The fill encountered in the northwestern portion of the site consists of brown, medium dense, silty sand which was apparently placed to create more suitable agricultural space. TECTONIC SETTINS: Several small faults have been mapped in the vicinity of the project site and faults may possibly underlie the subject site. The faults in this area are generally classified as inactive and are present in the Eocene-age materials in the area. No evidence of faulting was observed in the Quaternary-age sediments at the site and any faults present in the underlying Eocene-age materials should be of no consequence to the project. A review of available geologic maps indicates that the subject site is located approximately 7 miles east of the extension of the Rose Canyon Fault Zone. The Rose Canyon Fault Zone is a series of northwest trending faults of Quaternary age that is currently classified as potentially active rather than active, according to the criteria of the California Division of Mines and Geology. It should be recognized that Southern California is characterized by major, active fault zones that could possible affect the subject site. The nearest of these is the Elsinore Fault Zone, located approximately 24 miles to the northeast. 6EOLO61 C HAZARDS: The subject site is located in an area which is rela- tively free of significant geologic hazards. The most likely geologic hazard to affect the site is groundshaking as a result of movement along one of the major, active fault zones mentioned previously. Based ‘on a SOUTHERN CAL,FC)RNIA 901L AND TESTINO. I N c. SCS&T 14067 August 18, 1982 Page 5 maximum probable earthquake of 7.3 magnitude along the Elsinore Fault Zone, maximum bedrock acceleration at the-site could be on the order of 0.2 g. Construction in accordance with the minimum standards of the Uniform Building Code and local governing agencies should minimize poten- tial damage due to seismic activity. Other potential geologic hazards such a stsunamis, seiches, liquefaction, or landsliding should be considered to be negligible or nonexistent. RECOME~ATIONS AM CONCLUSIONS SITE PREPMATION GENERAL: It is our opinion that all areas which are to support fill and/or structural loads (including streets) should have the existing nonengineered fill and loose native soils removed to firm natural ground. Firm natural ground is defined as native soil which possesses an in-situ density equal to or greater than 85% of its maximum dry density. The soils exposed at the base of these excavations should be scarified a depth of 12 inches, watered to optimum requirements and compacted to at least 90% of their maximum dry density. The removed soils may then be replaced as properly compacted fill densified to the above indicated requirements. Based upon the results of this study, it appears that the maximum depth of removal and recompaction will be on the order of seven feet in the vicin- ity of Trench No. 1. It is further reconended that Southern California Soil & Testing, Inc. be present during grading operations to verify com- pliance with these recommendations. SUBDNAINS: It is our opinion that a subdrain should be installed in the drainage swale in the southeastern portion of this site that is to be filled in. We recommend that this drain extend at least 5 feet beyond the daylight point of this fill. The approximate location of this drain is .- SC)“THERN CALIFORNIA 901L 4NO TESTINO. I N c. SCS&T 14067 August 18, 1982 Page 6 shown on Plate No. 1, however, the actual positioning should be determined during grading operations. The following Figure Number 1 provides a detail for this drain. EARTHWORK: All earthwork and grading contemplated for site preparation should be accomplished in accordance with the attached Recommended Grading Specifications and Special Provisions. All special site preparation recommmendations presented in the sections above will supersede those in the standard Recommended Grading Specifications. All embankments, struc- tural fill and fill should be compacted to a minimum of 90%. Utility trench backfill beneath asphalt pavements should be compacted to a minimum of 90% of its maximum dry density. The maximum dry density of each soil type should be determined in accordance with A.S.T.M. Test Method 1557-78, Method A or C. FOUKl ATI ONS GENERAL i It is our opinion that all permanent structures may be supported by conventional spread footings. All footings should be founded at least 12 inches below lowest adjacent finished grade with a minimum width of 12 inches. An allowable soil bearing pressure of 2000 psf may be used for foundation design. All continuous footings should also be reinforced with at least one No. 4 bar top and bottom. LATERAL RESISTIANCE: Resistance to lateral loads may be provided by friction at the base of the footing and by passive pressure against the adjacent soil. For concrete footings on compacted soil, a coefficient of friction of 0.40 may be used. For calculating passive pressure, an equiva- lent fluid unit weight of 250 pounds per cubic foot may be used. Passive pressure should not exceed 1,500 pounds per square foot. When combining frictional and passive resistance, the latter should be reduced by one- third. aolJT”ERN CALIFORN,A 901L AND TESTINO, I N c. ORIGINAL GROUND A’. . \ * ‘I.<:< -. . . ’ ; .;/ . * - ,g I \ . . . . - a \A. . . .- ,\ . .‘,‘\ ._ ** ;-.’ . * q./& NAIUKAL GROUND ,LEANOUT EXCAVATION 4:' MIN / E M!N ' CRUSHED ROCK ^^....mL^ ;, UK CLASS II PERMEndLE COMPLETELY SURKuI;?wtu BY FILTER FABRIC -- _ _ _ _ _ _ ------"I MATERIAL / 4" DIAMETER PERFORATED PIPE - MINIMUM 1% SLOPE PIPE DEPTH OF FILL MATERIAL OVER SUBDRAIN ADS (CORRUGATED POLETHYLENEE 8 TRANSITE UNDERDRAIN 20 PVC OR ABS: SDR 35 SDR 21 SCHEMATIC ONLY NOT TO SCALE SOUTHERN CALIFORNIA SOIL & TESTINQ, INC. El Camino Estates .I.0 II".CID.L. .TCI..T El Camino Real .AN 01.00. EALWOlNIA .*,*a Carlsbad, CA BY DATE TYPICAL CANYON SUBDRAIN RRR 8-18-82 JOB NO. 14067 I Fiaure No. 1 SCS&T 14067 August 18, 1982 Page 8 SETTLERERT CHARACTER1 STlCS: The anticipated total and/or differential settlements for the proposed structure may be considered to be within tolerable limits provided the recomnendations presented in this report are followed. EXPANSIVE CHARACTERISTICS: The prevailing foundation soils were found to be nondetrimentally expansive and will not require special consideration and/or design. SLOPE STARILlTY The cut and fill slopes constructed from the native on-site materials will be stable with relation to deep-seated failures if constructed at or flatter than the following recommended slope ratios expressed in hori- zontal to vertical units for the indicated heights: Cut Slopes to 35 Feet in Height: 1.5:l to 50 Feet in Height: 2:l Fill Slopes to 25 Feet in Height: 1.5:1 to 40 Feet in Height: 2:l The above maximum heights were determined by using a factor of safety of 1.5. It is also recommended that footings not be founded nearer than five feet measured horizontally inward from the face of the slopes. Slopes should be planted with erosion resisting plants and natural drainage should be directed away from the tops of all slopes. It is further recommended that clayey soils not be used on the outer 3 feet of the proposed fill slopes and that the face of these fill sloeps be rolled at intervals not exceed- ing four feet in height. SOUTHERN CALIFORNIA 901L AND TESTINO, I N c. SCS&T 14067 August 18, 1982 Page 9 E!RTtlUORK SIWNKAGE AN0 SUBSIDENCE Based upon a review of the field and laboratory data, it appears that the native soils will exhibit an overall shrinkage and susidence loss on the order of lo-15% during grading operations. It should be recognized that the above value is only an estimate provided for assistance in preparing the project grading plan. Provisions should be made for final adjustment of grades to balance the on-site earthwork. LIHITATIONS REVIEW, OBSERVATION AN0 TESTINB The recormnendations presented in this report are contingent upon our review of final plans and specifications. The soil engineer and engineer- ing geologist should review and verify the compliance of the final grading plan with this report and with Chaper 70 of the Uniform Building Code. It is recommended that the soil and foundation engineer be retained to provide continuous soil engineering services during the earthwork opera- tions. This is to observe compliance with the design concepts, specifica- tions or recommendations and to allow design changes in the event that subsurface conditions differ from those anticipated prior to start of construction. UNIFCMITV OF CONOITIONS The recomnendations and opinions expressed in this report reflect our best estimate of the project requirements based on an evaluation of the subsur- face soil conditions encountered at the subsurface exploration locations and the assumption that the soil conditions do not deviate appreciably from those encountered. It should be recognized that the performance of DOUTHERN enLIl=ol?NIA 901L AND T E 9 T I N D. I N c. SCS&T 14067 August 18, 1982 Page 10 the foundations and/or cut and fill slopes may be influenced by undis- closed or unforeseen variations in the soil conditions that may occur in 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 soils engineer so that he may make modifi- cations if necessary. CHANGE IN SCOPE This office should be advised of any changes in the project scope or pro- posed site grading so that it may be determined if the recommendations contained herein are appropriate. This should be verified in writing or modified by a written addendum. TItQ LIMITATIONS 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. In addition, changes in the State-of-the-Art and/or Government Codes may occur. Due to such changes, the findings of this report may be invalidated wholly or in part by changes beyond our control. Therefore, this report should not be relied upon after a period of two years without a review by us verifying the suitability of the conclusions and recommendations. PROFESSIONAL STANMiD In the performance of our professional services, we comply with that level of care and skill ordinarily exercised by members of our profession cur- rently practicing under similar conditions and in the same locality. The client recognizes that subsurface conditions may vary from those encoun- SOUTHERN C*LlFDRNtA SDIL *ND TESTINO. I N c. SCS&T 14067 August 18, 1982 Page 11 tered at the locations where our borings, surveys, and explorations are made, and that our data, interpretations, and recommendations are based solely on the information obtained by us. We will be responsible for those data, interpretations, and recommendations, but shall not be respon- sible for the interpretations by others of the information developed. Our services consist of professional consultation and observation only, and no warranty of any kind whatsoever, express 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. CLIENT’S RESPONSIBILITY It is the responsibility of Hr. Art Anderson, or his 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 his responsibility to take the necessary measures to insure that the contractor and his subcontractors carry out such recommendations during construction. FIELD EXPLORATIONS Four subsurface explorations were made at the locations indicated on the attached Plate Numbers 1 on August 3, 1982. These explorations consisted of trenches dug by means of a backhoe. The field work was conducted under the observation of our engineering geology personnel. The explorations were carefully logged when made. These logs are present- ed on the following Plate Numbers 3 through 6. The soils are described in accordance with the Unified Soils Classification System as illustrated on the attached simplified chart Plate No. 2. In addition, a verbal textural DOUTHERN CALIFORN,A SOIL AND T E 5 T I N 0, I N c. SCS&T 14067 August 18, 1982 Page 12 description, the wet color, the apparent moisture and the density or consistency are presented. The density of granular material is given as either very loose, loose, medium dense, dense or very dense. The consis- tency of silts or clays is given as either very soft, soft, medium stiff, stiff, very stiff, or hard. Disturbed and undisturbed samples of typical and representative soils were obtained and returned to the laboratory for testing. LABORATORY TESTI ffi Laboratory tests were performed in accordance with the generally accepted American Society for Testing and Materials (A.S.T.M.) test methods or suggested procedures. A brief description of the tests performed is presented below: a) WJISTURE-DENSITY: Field moisture content and dry density were determined for representative undisturbed samples. This informa- tion was an aid to classification and permitted recognition of variations in material consistency with depth. The dry unit weight is determined in pounds per cubic foot, and the field moisture content is determined as a percentage of the soil's dry weight. The results are summarized in the trench logs. b) aASSIFIcATI01: Field classifications were verified in the laboratory by visual examination. The final soil classifications are in accordance with the Unified Soil Classification System. SCS&T 14067 August 18, 1982 Page 13 cl DIRECT SHEAR TESTS: Direct shear tests were performed to deter- mine the failure envelope based on yield shear strength. The shear box was designed to accomodate a sample having a diameter of 2.375 inches or 2.50 inches and a height of 1.0 inch. Samples were tested at different vertical loads and at saturated moisture content. The shear stress was applied at a constant rate of strain of approximately 0.05 inches 'per minute. The results of these tests are presented on attached Plate Number 7. d) COMPACTION TEST: The maximum dry density and optimum moisture content of typical soils were determined in the laboratory in accordance with A.S.T.M. Standard Test D-1557-78, Method A. The results of these tests are presented on the attached Plate Number e) EXPANSION TEST: The expansive potential of clayey soils was determined in accordance with the following test procedures and the results of these tests appear on Plate Number 7. Allow the trimmed, undisturbed or remolded sample to air dry to a constant moisture content, at a temperature of 100 degrees F. Place the dried sample in the consolidometer and allow to compress under a load of 150 psf. Allow moisture to contact the sample and measure its expansion from an air dried to saturated condition. ODUTHERN CALLIFORNIA soil. *ND TESTINO. tNC. SUBSURFACE EXPLORATION LEGEND LRII~XED SOlL cLAs.sIP?.cATIoH czElhR* SOXL DESCRIPTION GROUP SY?48OL TYPICAL NAPLES 1. COARSE GRAINED, HOT* ellan half Of material is larser than 80. 200 sieve size. w CLEAN GRAVELS QT we11 graded gravels, gravel- More than half of *an* mixtures, little or no coarse traction is fines. larger than NO. 4 GP EYmr1y graded gravels, gravely sieve size but sand mixtures, lit,tla or no smaller than 3". fi"SS. GRAVELS WITH FINES GM Silty gr?a"els, poorly graded mppreciable amount gravel-sand-silt mixtures. of tines) GC Clayey gravels, poorly graded gravel-sand. clay mixtures. m CLEAN SANDS SW we11 graded sand,gra"elly 4rlore than half of sands, little or no fines. coarse fraction is SP Poorly graded sa"ds,gra"el~y smaller man NO. 4 *an&, little or no fines. sieve size. SANDS WITH FINES sn silty sands, poorly graded (Appreciable amount sand and silt mixtures. Of fines) SC Clayey sands. poorly graded sand and clay mixtures. 11. PINE GP.ATNED, nore the" hhlf of material is smaller man NO. 200 sieve sire. SILTS AND CIAYS ML Inorganic silts and very fine sande. rock flour, sandy silt or clayey-silt-sand mixtures with slight plast- icity Liquid Limit CL Inorganic clays of low to less than 50 medium plasticity,gravelly clays, sandy clays,silty clays, lea" clays. or.8 Organic silts and organic silty clays of low plasticiey SILTS AND CLAYS EM Inorqanic silts, micaceous or d~e.tanaceoue tine Tandy orlar~f" roils, clastlc Liquid Limit CH mcrrganic days of high greater ths" 50 plase.icity. Cat clays. on organic clays of medium to high plasticity. HIGHLY ORGANIC so*Ls m Peat and other highly organk soils. 3 - Water level at time of excavation or as indicated US - Undisturbed, driven ring sample or tube sample CK - Undisturbed chnk sample BG - Bulk sample SOUTHERN CALIFORNIA SOIL 6 TESTINO, INC. . ..m ",".IIOAL. .TCI..T ..N o,.oa. CILlCDLINlA .m')*m El Camho Estates Carlsbad, California BY RR DATE 8-18-82 JOB NO. 14067 Plate No. 2 1- 2- 3- CK -B 4- 5- 6- 7- CK 8 B 9- IO- I1 - 12-- 6 c a JU :; z ;1 - :L - ic/ :L - TRENCH NUMBER 1 ELEVATION DESCRIPTION SANDY CLAY (TOPSOIL) VERY CLAYEY SAND (ALLUVIUM) DARK RED-BRN RED-BRN MOIST MOIST STIFF MEDIUM DENSE 37.1 - - 15.6 - -. 2 wz >o cc Qcl ;$ ‘Lx 3 - - SUESURFACE EXPLORATION LOO SOUTHERN CALIFORNIA LOGGED WY DATE LOGGEO: SOIL & TESTINO, INC. CRB 8-3-82 JOB NUMBER: 14067 Plate NO. 3 ; f 6 2 TRENCH NUMEER 2 2 ! t II 6:x 5: ZZk : g” wz AZ ELEVATION WWLn ?I- ,; ‘0 u ;; : :: EkZ : ; $i $ul 2; i 2” z;: -+ ! 2 :$ z 0.0 a.2 :gu ii “; c> 03 cl0 ; q ASCRIPTION 8 CL SANDY CLAY WITH DEBRIS BRN MOIST MEDIUM STIFF 1- 2- (FILL) 3 CL SANDY CLAY DARK-BRN MOIST STIFF 4- CK (NATIVE ALLUVIUM) 101.8 12.9 82 5- 6- 7- CK 106.0 16.6 85 B- 9- 10 SC/ .VERY SILTY AND CLAYEY SAND GREENISH MOIST DENSE CL BRN il - _ CK iv (FORMATIONAL) 12- 13 SOUTHERN CALIFORNIA SOIL 6 TESTINQ, INC. ; f z ; TRENCH NUMBER 3 2 : ; iI '> a 5: ;;t : ul~u.7 1L JI- :; >0 Y ELEVATION WWLn $ : :: pi g Lu 2: : UJLO i ? OJ 2” i CL0 az pi; ;j Y! a.5 “8: i z n’5 0 0 ” DESCRIPTION : SC/ VERY CLAYEY SAND RED-BRN MOIST CL MEDIUM (TOPSOIL) DENSE 1 CK SW VERY SILTY AND CLAYEY SAND YEL-BRN MOIST MEDIUM ML & DENSE TO 2- x/ DENSE 101.7 14.7 82 CK CL 3-B (FORMATIONAL) 4- 5- 6- 7- 8- CK 9- IO- I1 - 12 SOUTHERN CALIFORNIA SOIL 6 TESTINQ, INC. 2 F 6 2 TRENCH NUMBER 4 7 E ! : >> 2 Sk ;:t : WE -‘u ili- 5+ YZ “, ELEVATION if; OK : :: CL : i; ; : “t L i :x; 2; i a Z” 05 -+ i 0.0 az a (D a> aoa 6 ‘; a> ; cl0 0 DESCRIPTION : SM SILTY SAND BRN HUMID LOOSE TO TO MOIST MEDIUM 1- (FILL) DENSE 2- CK 99.7 4.5 80 3 B 4- 5- 6 CK CL SANDY CLAY GRY MOIST STIFF 103.2 15.5 83 7- (NATIVE ALLUVIUM) 8- 9- ID SUBSURFACE EXPLORATION LOO SOUTHERN CALIFORNIA LDGGED BY: SOIL &TESTING, INC. CRB DATE LOGGEO: 8-3-82 JOB NUMeER: 14067 Plate No. 6 DIRECT SHEAR TEST RESULTS DESCRIPTION MAXIMUM DENSITY & OPTIMUM MOISTURE CONTENT A.S.T.M.: 1557-78 METHOD: A DESCRIPTION . EXPANSION TEST RESULTS CONDITION I INITIAL M.C.(%) NORMAL STRESS(p;f) EXPANSION(%) SOUTHERN CALIFORNIA SOIL & TESTING LAB, INC. SPaO q VLCIDAL. wrR.rnT q AN q 1m00. CALIPOINIA SSlPO El Camino Estates Carlsbad, California BY RR DATE 8-18-82 JoB No' 14067 Plate No. 7 SCS&T 14067 August 18, 1982 Appendix A, Page 1 EL CAMHO ESTATES RECOMENDED GRAD1116 SPECIFICATIONS - GENERAL PROVISIONS GENERAL INlENT The intent of these specifications is to establish procedures for clear- ing, compacting natural ground, preparing areas to be filled, and placing and compacting fill soils to the lines and grades shown on the accepted plans. The recormnendations contained in the preliminary soil investiga- tion report and/or the attached Special Provisions are a part of the Recomnended Grading Specifications and shall supersede the provisions contained hereinafter in the case of conflict. These specifications shall only be used in conjunction with the soil report for which they are a part. No deviation from these specifications will be allowed, except where specified in the soil report or in other written coavnunication signed by the Soil Engineer. OKSERVATION AN0 TESTING Southern California Soil & Testing, Inc. shall be retained as the Soil Engineer to observe and test the earthwork in accordance with these speci- fications. It will be necessary that the Soil Engineer or his representa- tive provide adequate observation so that he may provide an opinion that the work was or was not accomplished as specified. It shall be the. re- sponsibility of the contractor to assist the soil engineer and to keep him apprised of work schedules, changes and new information and data so that he may provide these opinions. In the event that any unusual conditions not covered by the special provisions or preliminary soil report are encountered during the grading operations, the Soil Engineer shall be contacted for further recommendations. SCS&T 14067 August 18, 1982 Appendix A, Page 2 If, in the opinion of the Soil Engineer, substandard conditions are en- countered, such as; questionable or unsuitable soil, unacceptable moisture content, inadequate compaction, adverse weather, etc., he will be empower- ed to either stop construction until the conditions are remedied or cor- rected or recommend rejection of this work. Test methods used to determine the degree of compaction should be per- formed in accordance with the following American Society for Testing and Materials test methods: Maximum Density & Optimum Moisture Content - A.S.:.M. D-1557-78. Density of Soil In-Place - A.S.T.M. D-1556-64 or A.S.T.M. D-2922. All densities shall be expressed iri terms of Relative Compaction as deter- mined by the foregoing A.S.T.M. testing procedures. PREPARATION OF AREAS TO RECEIVE FILL All vegetation, brush and debris derived from clearing operations shall be removed, and legally disposed of. All areas disturbed by site grading should be left in a neat and finished apperance, free from unsightly debris. Any abandoned buried structures encountered during grading operations must be totally removed. All underground utilities to be abandoned beneath any proposed structure should be removed from within 10 feet of the structure and properly capped off. The resulting depressions from the above des- cribed procedures should be backfilled with acceptable soil that is com- pacted to the requirements of the Soil Engineer. This includes, but is not limited to, septic tanks, fuel tanks, sewer lines or leach ljnes, SOUTHERN CAL,FORNIA SOIL Al-40 TESTINlj. INC SCS&T 14067 August 18, 1982 Appendix A, Page 3 storm drains and water lines. Any buried structures or utilities not to be abandoned should be investigated by the Soil Engineer to determine if any special recotnnendation will be necessary. All water wells which will be abandoned should be backfilled and capped in accordance to the requirements set forth in the Geotechnical Report. The top of the cap should be at least 4 feet below finish grade or 3 feet below the bottom of footing whichever is greater. The type of cap will depend on the diameter of the well and should be determined by the Soil Engineer and/or a qualified Structural Engineer. When the slope of the natural ground receiving fill exceeds 20% (5 hori- zontal units to 1 vertical unit), the original ground shall be stepped or benched. Benches shall be cut to a firm competent soil condition. The lower bench shall be at least 10 feet wide or 1 l/2 times the equipment width which ever is greater and shall be sloped back into the hillside at a gradVent of not less than two (2) percent. All other benches should be at least 6 feet wide. The horizontal portion of each bench shall be compacted prior to receiving fill as specified hereinbefore for compacted natural ground. Ground slopes flatter than 20% shall be benched when considered necessary by the Soil Engineer. After clearing or benching, the natural ground in areas to be filled shall be scarified to a depth of 6 inches, brought to the proper moisture con- tent, compacted and tested for the minimum degree of compaction in the Special Provisions or the recommendation contained in the preliminary soil investigation report. All loose soils in excess of 6 inches thick should be removed to firm natural ground which is defined as natural soil which possesses an in-situ density of at least 85% of its maximum dry density. SO”T”LRI-4 CALIFORNIA 9 0 I L AND TESTING. INC. SCS&T 14067 August 18, 1982 Appendix A, Page 4 FILL MTERIM Materials placed in the fill shall be approved by the soil engineer and shall be free of vegetable matter and other deleterious substances. Gran- ular soil shall contain sufficient fine material to fill the voids. The definition and disposition of oversized rocks, expansive and/or detrimen- tal soils are covered in the soils report or Special Provisions. Expan- sive soils, soils of poor gradation, or soils with low strength character- istics may be thoroughly mixed with other soils to provide satisfactory fill material, but only with the explicit consent of the soil engineer. Any ;import material shall be approved by the Soil Engineer before being brought to the site. PLACIRG AMI COMPACTIOW OF FILL Approved fill material shall be placed in areas prepared to receive fill in layers not to exceed 6 inches in compacted thickness. Each layer shall have a uniform moisture content in the rdnge that will allow the compac- tion effort to be efficiently applied to achieve the specified degree of compaction. Each layer shall be uniformly compacted to the minimum speci- fied degree of compaction with equipment of adequate size to economically compact the layer. Compaction equipment should either be specifically designed for soil compaction or of proven reliability. The minimum degree of compaction to be achieved is specified in either the Special Provis.ions or the recommendations contained in the preliminary soil investigation report. When the structural fill material includes rocks, no rocks will be allowed to nest and all voids must be carefully filled with soil such that the minimum degree of compaction recomnended in the Special Provisions is SOUTHERN CALIFORNIA 901L ANO T E 9 T I N -3. I N c. SCS&T 141367 August 18, 1982 Appendix A, Page 5 achieved. The maximum size and spacing of rock permitted in structural fills and in non-structural fills is discussed in the soil report, when applicable. Field observation and compaction tests to estimate the degree of compac- tion of the fill will be taken by the Soil Engineer or his representative. The location and frequency of the tests shall be at the Soil Engineer's discretion. When the compaction test indicates that a particular layer is less than the required degree of compaction, the layer shall be reworked to the satisfaction of the Soil Engineer and until the desired relative compaction has been obtained. Fill slopes shall be compacted by means of sheepsfoot rollers or other suitable equipment. Compaction by sheepsfoot rollers shall be at vertical intervals of not greater than four feet. In addition, fill slopes at ratios. of two horizontal to one vertical or flatter, should be track- rolled'. Steeper fill slopes shall be over-built and cut-back to finish contours. Slope compaction operations shall result in all fill material six or more inches inward from the finished face of the slope having a relative compaction of at least 90% of maximum dry density or that speci- fied in the Special Provisions section of this specification. The compac- tion operation on the slopes shall be continued until the Soil Engineer is satisfied that the slopes will be stable in regards to surficial stabil- ity. Slope tests will be made by the Soils Engineer during construction of the slopes to determine if the required compaction is being achieved. Where failing tests occur or other field problems arise, the Contractor will be notified that day of such conditions by written communication from the Soil Engineer in the form of a daily field report. SOUTHERN CALIFORN,A SOIL AND TESTINC1. I N c. SCS&T 14067 August 18, 1982 Appendix A, Page 6 If the method of achieving the required slope compaction selected by the Contractor fails to produce the necessary results, the Contractor shall rework or rebuild such slopes until the required degree of compaction is obtained, at no additional cost to the Owner or Soils Engineer. CUT SLOPES The Engineering Geologist shall inspect all cut slopes excavated in rock or lithified formational material during the grading operations at inter- vals determined at his discretion. If any conditions not anticipated in the preliminary report such as perched water, seepage, lenticular or confined strata of a potentially adverse nature, unfavorably inclined bedding, joints or fault planes are encountered during grading, these conditions shall be analyzed by the Engineering Geologist and Soil Engi- neer to determine if mitigating measures are necessary. Unless otherwise specified in the soil and geological report, no cut slopes shall be excavated higher or steeper than that allowed by the ordinances of the controlling governmental agency. ERGIWEERIWG OBSERVATION Field observation by the Soil Engineer or his representative shall be made during the filling and compacting operations so that he can express his opinion regarding the conformance of the grading with acceptable standards of practice. The presence of the Soil Engineer or his representative or the observation and testing shall not release the Grading Contractor from his duty to compact all fill material to the specified degree of compac- tion. SOUTHERN CALIFORNIA 5 0 t L ANCI TESTINO. INC. SCS&T 14067 August 18, 1982 Appendix A, Page 7 SEASON LIMITS Fill shall not be placed during unfavorable weather conditions. When work is interrupted by heavy rain, filling operations shall not be resumed until the proper moisture content and density of the fill materials can be achieved. Damaged site conditions resulting from weather or acts of God shall be repaired before acceptance of work. RECOMMENDED GRADIffi SPECIFICATIONS-SPECIAL PROVISIONS The minima degree of compaction to be obtained in compacting natural ground, in the compacted fill, and in the compacted backfill shall be at least 90 percent. Detrimentally expansive soil is defined as soil which will swell more than 3 percent against a pressure of 150 pounds per square foot from a condi- tion of 90 percent of maximum dry density and air dried moisture content to saturation. Oversized fill material is defined as rocks or lumps over 6 inches in diameter. At least 40 percent of the fill soils shall pass through a No. 4 U.S. Standard Sieve. Transition Lots: Where transitions between cut and fill occur within the proposed building pad, the cut portion should be undercut a minimum of one foot below the base of the proposed footings and recompacted as structural backfill. SO”TWERr-4 CALIFORNIA 901L AND TESTING. 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