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Home My WebLink AboutMS 882; LA CORUNA; Minor Subdivision (MS)M5 fM >^ RECEIVED JAN 0 9 2003 ENGINEERING DEPART^AENT SOUTHERN CALIFORNIA SOIL AND TESTING, INC. January 30, 1991 Mr. Rdhit Saraiya 3021 Del Rey Avenue Carlsbad, Califomia 92009 SCS&T 8921145 Report No. 2 SUBJECT: Review of Grading Plans, Proposed Residential SutxiLvision, MS882/ PUD 89-12, La Corvma Place, Carlsbad, Califomia. REFERENCE; "R^ort of l^xSated ReccaMvendations, Proposed Residential Subdivision;" Southem Califomia Soil and Testing, Inc.; Octjober 11, 1989. Dear Mr. Saraiya: In accordance with the request from Mr. Josejii Lukoski tliis letter has been prepared to verify that we have reviewed the grading plans for the subject project dat:ed December 20, 1990. The plans were found to be in accordance with the recommendations provided in the referenced report. The recommendations contained in said report are still applicable to the project and should be itrplemented. This opportunity to be of professional service is aj^reciated. Respectfiilly sutitdtted, CFORjqiA^IL & TESTING, INC. Daniel B.^Mler, R.C.E. #36067 DBA:raw cc: (5) Submitted (1) Mr. Joseph Lukoski (1) SCS&T, Escondido 6280 RIVERDALE STREET • SAN DIEGO, CA 92120 • 619-280-4321, FAX 619-280-4717 • P.O. BOX 600627, SAN DIEGO, CA 92160 678 ENTERPRISE STREET • ESCONDIDO, CA 92029 • 619-746-4544. FAX 619-746-6579 I I I s i i i 1 m REPCRT QF UPDMED RECCMMEWDKnCNS PROPOSED RESiraaWIAL SUBDIVISION IA CXMJNft. PLflCE CflRLSBftD, CftLIPORNIA PREPARED FOR: Mr. Rohit Saraiya 3021 Del Rey Avenue Carlsbad, Califomia 92009 PREPARED BY: Southem Califomia Soil & TestiiK^, Inc. Post Office Box 20627 6280 Riverdale Street San Diego, Califomia 92120 m SOUTHERN CALIFORNIA SOIL AND TESTING, INC. 62BD RIVERDALE ST. SAN DIEGO, CALIF. 921ZD • TELE 280-4321 • P.O. BOX 2D627 SAN DIEGO, CALIF. 9Z12D CALIF. 92025 • TELE 74&-454A ENTERPRISE ESCONDIDO, October 11, 1989 Mr. Rohit Saraiya 3021 Del Rey Avenue Carlsbad, Califomia 92009 SCS&T 8921145 Report No. 1 • i i I 1 I I I \ SUBJECT: Report of Updated Iteconinendations, Proposed Residential Subdivision, La Coruna Place, Carlsbad, California. REFERENCE; "Preliminary Geotechnical Investigation, Proposed Condominium Project;" Southem Califomia Soil and Testing, Inc.; SCS&T 14044; September 29, 1982. Dear Mr. Saraiya: In accordance with your request, we have prepared this update report for the subject project. The purpose of this report was to present update recortinendations vMch will reflect ciorrent geotechniccLL standards arvi the proposed developtent scheme. In addition, we will address the st:ability of existing and proposed slopes as requested by the City of Carlsbad Planning Department. PROJECT EMBSCRIPTICN It is our understanding that the subject project will consist of the construction of three one and/or two-story split level residential structures. The buildings will be of wood-frame and masoruy construction. SCS&T 8921145 October 11, 1989 Page 2 Shallow foundations and conventional slab-on-grade floor systems are anticipated. Masonry retaining walls up to 12 feet high are anticipated. Grading will consist of cuts and fills less than 11 feet and 13 feet, respectively. REOCMMENDKnCKS GEWERAL The following recomraendations are based on the findings of the referenced report and a site reconnaissance performed by a member of our engineering geology staff. In general, the soil conditions at the site remain vmchanged since the time of our original investigation. An existing off-site steep fill slope (Lot 159) exhibits what appears to be a surficial failure. This condition is addressed in the slope stability analysis portion of this report. (S»DIN5 sms FREFARHEIGN; Site preparation should begin with the ratoval of all existing vegetation and deleterious matter from the areas of the site to be developed. Existing topsoils and allvtvium should be removed to firm natvural ground. Firm natural ground is defined as undisturbed soil having a minimam in-place density of 85 percent as determined in accordance with ASTM D1557-78 Method A or C. Removal operations should be extended to a mininum distiance of five feet from the perimeter of the inprovements or propertry line, v*iichever is less. The bottom of the excavations should^ be scarified to a depth of 12 inches, moisture conditioned and reconpacted to at least 90 percent. LOT IXSXBOJIs It is recommended that the cut portion of proposed cut-fill pads be undercut to a depth of three feet. The bottom of the luidercut should have a minimum inclination of one percent towards the fill portion of the pad. The undercut area should be backfilled vith properly compacted fill. SCS&T 8921145 October 11, 1989 Page 3 SELECT GRADING: It is anticipated that highly expansive soils will be encountered at depths below approximately 164 feet MSL. Unless select grading is performed this condition will require special foundation consideration. Select grading consist of capping the proposed building pads with a minimum foxir-foot-layer of nondetrimentally expansive soil (expansion index less than 50). Foundation recommendations for both altematives are provided herein. It is further recommended that expansive soils not be placed within a distance of ten feet from the face of proposed fill slopes. SURFACE ERAnCRGB; It is recommended t±at all surface drainage be directed away from t±e proposed st:mctures and the top of slopes. Ponding of water should not be allowed adjacent to the foundations. EAR311HGRK: All earthvrork and grading contenplated for site preparation should be accomplished in accordance with the att:ached Recomtended Grading Specifications and Special Provisions. All special site preparation reconnendations presented in the sections above will supersede those in the Standard Recommended Grading Specifications. All enrbankmentis, structural fill and fill should be cotpacted to at least 90% relative corpaction at or slightly over optimum moisture content. Utility trench backf ill within five feet of the proposed structures and beneatJi asphalt pavements should be conpacted to minimum of 90% of its maximum dry density. The upper tv^lve inches of subgrade beneath paved areas should be cottpacted to 95% of its maximum dry density. This compaction should be obtained by the paving contractor just prior to placing the aggregate base itaterial and should not be part of the mass grading requirements. The maximum dry density of each soil type should be detentdned in accordance with A.S.T.M. Test Method D-1557-78, Method A or C. SLOPE STABrLrry OBNERAL: The general gross stability of the existing and proposed site config\u:ation was analyzed utilizing the Stabrg Conputer Slope St:ability Analysis and found to be in excess of 1.5 (see attached Plates 1 through 4 and J^jpendix A). SCS&T 8921145 October 11, 1989 Page 4 STABUJTy OF toon FACING SLOPES: The existing north facing slope has a general 2"1 (horizontal to vertical) inclination. Ffowever in some areas the slope is steeper and has a 1.4:1 inclination (see Plates Number 1 and 3). in our opinion this slope possesses an adequate factor of safetry with respect to deep seated rotational failure. A reconnaissance performed by a meitber of our engineering geology staff did not indicate any signs of surficial slope instability. STABILITy OF OOFF-SITE FILL SLOPE: A steep off-site fill slope exist:s soutJl of the subject site (Lot 159). The slope has an overall height of 22 feet. Approximately the lovrer half has a 1.8:1 (horizontal to vertical). The upper portion has an inclination of 1:1. Some surficial failure areas were observed in the upper portion. It is not known whether the steep portion of the slope was constrxtcted in conjunction with grading of the existing building pad or vAiether was done afterwards as part of the construction of exterior miscellaneous inprovements. We have no knowledge or opinion as to the proper construction and ccmpaction of the existing off-site fill slope. However, due to its steepness it is reasonable to assxiroe that further deterioration may occur. In our opinion the proposed developtent will not influence the stability of the existing slope."However, due to the location of proposed tenporary cut slopes for retaining wall construction and the site topography, it is recommended that temporary cut slopes for the proposed driveway wall located along the southwestern property line and/or within 20 feet from it be shored. This will avoid going off-site with the cut slopes and encroaching into the existing fill slope. Furthermore, it is recommended that a chain link fence be installed at the top of the property line retaining wall below said slope to catch any potential sloughing. TEMPORRRT COT SLOPES: It is recommended that tenporary cut slopes exposing natural ground be constructed at a continuous 0.75:1 (horizontal to vertical) inclination. All temporary cut slopes should be aj^roved by the engineering geologist during constiruction to ascertain t±at no adverse conditions cu:e encountered. SCS&T 8921145 October 11, 1989 Page 5 SHORING RBaOMMENDftTICNS GEMERAL: A shoring system consisting of H-piles and vcoden lagging may be utilized for the support of vertical temporary cut slopes. It is our understanding that this system will renain as a pemranent earth ret:aining stiructure. The shoring system will be built by drilling 24-iiK:h diameter borings extending at least five feet below the bottom of the proposed excavation. H-piles are placed in the holes which are then backfilled with concrete to the bott:om of the proposed excavation. The remaining of the boring is backfilled with a lean cement mix. PASSIVE RESISXANCE: All allowable passive resistaiKre of 500 pounds per square foot of depth may be used for design purposes. This value should be limited to a maxiirum value of 6000 pounds per square foot. The upper foot should be neglected. A pressure diagram is provided below as Figure Number 1, 6000 PSF FIGURE 1 PASSIVE PRESSURE DIAGRAM AcnVE PRESSURES: The active lateral pressure for the on-site soils may be assimed to be equivalent to the pressures shown on either of the diagrams on the following page as Figure Number 2. SCS&T 8921145 October 11, 1989 Page 6 H 4- 0.1 H Q7H Q2H H LEVEL BACKFILL 29H psf 2:1 (HORIZONTAL TO VERTICAL) 39H psf 1.5:1 (HORIZONTAL TO VERTICAL) 59H psf FIGURE 2 ACTIVE PRESSURE DIAOIAHE 4-23H psf 32H psf 48H psf (A) SETfTT (S»DII15 (NQMIXnimiENEALLY EXPANSIVE SOILS) GENERAL: Conventional shallow foundations are recommended for the support of the proposed stiructiires. Footings should have a mininum depth of 18 inches below lowest adjacent finished pad grade. A mininum width of 12 inches and 24 inches is reccmmended for continuous and isolated footings, respectively. An allowable bearing capacity of 2000 psf may be assumed for said footings. These bearing capacities may be increased by one-third vAien considering wind and/or seismic forces. Footings located adjacent to or witJiin slopes should be extended to a depth svich that a ten-foot setback exists between the footings and the face of slopes. REINPORCEMENT: Continuous footings should be reinforced witJi at least one #5 bar positioned near the bottom of the footing and one #5 bar positioned near the top of the footing. This reinforcement is based on soil characteristics and is not int:ended to be in lieu of reinforcement necessary to satisfy stmctural considerations. SCS&T 8921145 October 11, 1989 Page 7 OONCREME SLABS-CN-GRADE: Concrete slabs-on-grade should have a thickness of four inches and be underlain by a four-inch blanket of clean, poorly graded, coarse sand or crushed rock. This blanket shoiiLd consist of 100 percent material passing the two-inch screen and no more than ten percent and five percent passing sieves #100 and #200, respectively. The slab should be reinforced witJi No.3 reinforcing bars placed at 24 inches on center each way. A 6"x6"-W1.43*?1.4 (6"x6"-6/6) welded wire nesh may be used in lieu of the irebars. Slab reinforcement shoiiLd be placed near tJie center of the slab. Where moisture sensitive floor coverings are planned, a visqueen barrier should be placed on top of the sand layer. A two-inch-thick layer of clean sand should be placed over the visqueen to allow proper concrete curing. EXTERIOR SLABS-CN-GRAEi:: Exterior slabs should have a mininum thickness of four inches. Walks or slabs five feet in width should be reinforced with 6"x6"-W1.4xW1.4 (6"x6"-10/10) welded wire mesh and provided with vreakened plane joints. Any slabs betvreen five and ten feet should be provided with longitudinal weakened plane joints at the center lines. Slabs exceeding ten feet in width should be provided witJi a veakened plane joint located three feet inside the exterior perimeter as indicated on attached Plate Number 5. Both txaverse and longitudinal veakened plane joints should be constructed as detcdled in Plate Number 5. Exterior slabs adjacent to doors and garage openings should be connected to the footings by dovels consisting of No. 3 reinforcing bars placed at 24-inch intervals extending 18 inches into the footing and the slab. - (B) EXISTINS CGNDinCNS (HIGHLY EXPANSIVE SOUS) GENERAL: Conventional shallow foundations are recommended for the support of the proposed sluxictures. Footings should have a mininum depth of 30 inches below lowest adjacent finished pad grade. A mininum width of 12 inches and 24 inches is recommended for continuous and isolated footings, respectively. An allowable bearing capacity of 2000 psf may be SCS&T 8921145 October 11, 1989 Page 8 assumed for said footings. These bearing capacities may be increased by one-third v*ien considering wind and/or seismic forces. Footings located adjacent to or within slopes should be extended to a deptJi such that a ten-foot setback exists betv^en the footings and the face of slopes. REINFCXCEMENT: Continuous footings should be reinforced with at least twD #5 bars positioned near the bottom of the footing and two #5 bars positioned near the top of the footing. This reinforcement is based on soil characteristics and is not intended to be in lieu of reinforcement necessary to satisfy structural considerations, COMZRETE SLABS-CN-GRAEE: Concrete slabs-on-grade supported on firm natured ground or conpacted fill should have a thickness of five inches and be underlain by a four-inch blanket of clean, pDorly graded, coarse sand or crushed rock. This blanket should consist of 100 percent material passing the tvro-inch screen and no more than ten percent and five percent passing sieves #100 and #200, respectively. The slab should be reinforced with No.3 reinforcing bars placed at 12 inches on center each way and extending at least 12 inches into the footings. Slab reinforcement should be placed near the~"center of the slab. Where moisture sensitive floor coverings are planned, a visqueen barrier should be placed on top of the sand layer. A two-inch-thick layer of clean sand should be placed over the visqueen to allow proper concrete curing. EXTERIOR MISCELLANEOUS IMPROVEMENTS: The intent of the aforementioned reconmendations is to minimize the potentied detirimental effect of the highly expansive foundation soils on the proposed structure. The client should recognize that some distress to exterior improvements such as slabs-on-grade, curbs and sidewalks may occur unless special consideration for the highly expansive soil is inplemented. Special consideration for expansive soils may include any of the following items or an appropriate combination: select grading to a mininum depth of twD feet, thicker slabs with additional reinforcement and/or moisture SCS&T 8921145 October 11, 1989 Page 9 i «l m il ii cut-off footings surrounding exterior improvements. The cost-benefit ratio of these recommendations versus a potential maintenance of exterior inprovements should be determined by the client. Hovrever, it should be recognized that distress of exterior inprovements should not detrinentally affect the stmctural integrity of the proposed stmcture. Irregardless of the method inplemented, it is suggested that planting and landscape adjacent to structures and hardscape areas be kept to a minimum. Drought resistance plants requiring nunimum irrigation are also suggested. SETTLEMEWT CSARAClSRISnCS: The anticipated total and/or differential settlements for the proposed stimcture will be within tolerable limits provided the recommervdations presented in this report are follovred. It should be recognized that minor cracks normally occur in concrete slabs and foundations due to shrinkage during curing or redist:ribution of stresses and some cracks may be anticipated. Such cracks are not necessarily an indication of excessive vertical movements. EARIH REXAINING fOVLLS PASSIVE PRESSURE: The passive pressiure for the prevailing soil conditions nay be considered to be 450 poimds per square foot per foot of depth. This pressure nay be increased one-third for seismic loading. The coefficient of friction for concrete to soil may be assuned to be 0.35 for the resistance to lateral movement. If select grading is not performed and retaining wall footings are founded on expansive soils, the aforementioned values should be reduced to 200 pcf and 0.2. When combining frictional and passive resistance, the former should be reduced by one-tJiird. The upper six inches of exterior retaining wall footings should not be included in passive pressure calculations. ACTIVE PRESSURE: The active soil pressures for the design of earth retaining stmctures are presented herein. SCS&T 8921145 October 11, 1989 Page 10 Backfill Restirained (horizontal to vertical)- Wall* Unrestxained Wall Level 2:1 1.5:1 29H psf 39H psf 59H psf 45 pcf 60 pcf 90 pcf * Uniform rectangular distribution, see Figure 2 H = wall height in feet These pressures do not consider any other surcharge. If any are anticipat:ed, this office should be cont:acted for the necessary increase in soil pressure. These values assunes a drained backfill condition. Vfeterproofing det:ails should be provided by the project architect. A wall drainage detail is provided on the attached Plate Number 6. BACKFILL: All backfill soils should be conpacted to at least 90% relative conpaction. Expansive or clayey soils should not be used for backfill material. The wall should not be backfilled until the masonry has reached an adequate st:rength. FACTOR CF SAFETY: The above values, witJi the exception of concrete to soils friction coefficient do not include a factor of safety, i^ropriate factors of safety should be incorporated into the design to prevent the walls from overtuming and sliding. If you have any questions regarding this report, or if we nay be of furtJier service, please do not hesitate to contact t:his office. Ftespee^tfully si±mitted, CKj.FOWjlIA SPJL/& TESTING, INC. Daniel B. Adler, R.C.E. #3ff037 DBA:JRH:mw cc: (6) Submitted (1) SCS&T, Escondido NO.1237 CERTIFIED , ^. \t/»A ENGINEERING /<« GEOLOGIST A SOUTH A MOHTh SAMDSTOMC SK.TSTONe.<Ct.AYftTONE CROSS SECTION A-A tCALf SLOPE STABILITY CALCULATIONS Janbu's Simplified Slope Stability Method \C0 = WH Tang!) FSzNctC^) Assume Homogeneous Strength Parameters throughout the slope JS (°) C(psf) W (pcf) Incl. H (ft) FS 30' 150" 125*-2:1 25 1.8 * Assumed Values Where: iT • Angle of Internal Friction C » Cohesion (psf) = Unit weight of Soil (pcf) H = Height of Slope (ft) FS = Factor of Safety yv SOUTHMM CALIFORNIA ^^h^ SOIL A TUTINQ.INC. PROPOSED RESIDENTIAL DEVELOPMENT Bt: DBA JOB NUMBBW; 8921145 DATE: 10-11-89 PLATE NO. WEAKENED PLANE•• •JOI TRANSVERSE WEAKENED PLANE JOINTS 6' ON CENTER :MAX.) 3' 10' SLAbS IN EXCESS OF 10 FEET IN WIDTH PLAN N • T. S . W , w/2 ,V.'/2 5'-10' SLABS 5 TO 10 FEET IN WIDTH 1.1/4 _ 1/8 TO 1/4 JOINT SEALER 6"x6"-10/10 WWM CONTINUOUS ' O.I • L 18" \6"x6"-10/10 WWM STRIP IN ADDITION TO CON- TINUOUS REINFORCEMENT DETAIL-WEAKENED PLANE JOINT N.T.S. SOUTHERN CALIFORNIA SOIL & TESTING , INC. • ••a HIV«RDAl.K •TRKKT • AN OIBaa, CAt-IFOHNIA ••^•0 PROPOSED RESIDENTIAL DEVELOPMENT BY JOB NO. ML DATE 10-11-89 WATER^IIOOF BACK OF WALL PER ARCHITECTS SPECIFICATIONS 3/4 INCH CRUSHED ROCK OR MARIDRAINSOOO OR EQUIVALENT GEOFABRIC BETWEEN ROCK AND SOIL 4" DIAMETER PERFORATED PIPE HOUSE ON QRADE SLAB i HOUSE RETAININQ WALL SUBDRAIN DETAIL NO SCALE SOUTHERN CALIFORNIA ^^F^ SOIL A TESTINQ.INC. PROPOSED RESIDENl •IAL DEVELOPMENT SOUTHERN CALIFORNIA ^^F^ SOIL A TESTINQ.INC. BY: DBA DATE: 10-11-89 SOUTHERN CALIFORNIA ^^F^ SOIL A TESTINQ.INC. JOB NUMBER: 8921145 PLATE NO. 6 APPENDIX A SOUTHERN CALIFOPIMIi SOIL & TESTING, INC. ********************************************** * * * SLOPE STABILITY ANALYSIS * * * ************** STABRG ***************** * * * PORTIONS (C) COPYRIOfT 1985, 1986 * * * * GEOSOFI * * * * ALL RIOWS RESERVED * * * ********************************************* RESIDENTIAL SUBDIVISK^, SCS&T 8921145, SECTION A, TRIAL B, 145AB l^kimROL DATA NUMBER OF SPECIFIED CENTERS NUMBER OF DEPTH LIMITING TANGENTS NUMBER OF VERTICAL SECTIONS NUMBER OF SOIL LAYER BOUNDARIES NUMBER OF PORE PRESSURE LINES 0 0 20 3 0 NUMBER OF POINTS DEFINING COHESION PROFILE 0 J|SEISMIC COEFFICIENT S1,S2 .00 .00 'SEARCH STARTS AT CENTER (1280.0, 700.0),WITH FINAL GRID OF 1.0 ALL CIRCLES PASS THROUGH THE POINT (1318.0, 911.0) iGECXffiTRY •SECTIONS 980.01029.01081.01107.01117.01137.01156.01186.01193.01206.01217.01225.01238.01245.01 CRACKS 802.0 802.0 810.0 815.0 820.0 830.0 835.0 850.0 855.0 860.0 866.0 870.0 87"^.n R7R n DARY 1 802.0 802.0 810.0 815.0 820.0 830.0 835.0 850.0 855.0 860.0 866.0 870.0 875.0 878.0 •I m m BOUNDJiRY 2 866.0 866.0 866.0 866.0 866.0 866.0 866.0 866.0 866.0 866.0 866.0 870.0 875.0 878.0 jjpOUNDARY 31000.01000.01000.01000.01000.01000.01000.01000.01000.01000.01000.01000.01000.01000.01 N i n i n I i I I I IL PROPERTIES LYER COffiSIO^ FRICTION ANGLE DENSITY 1 550.0 38.0 140.0 2 300.0 25.0 125.0 IMBER TANCSNT RADIUS (X) CENTER (Y) CENTER FS( BISHOP) FS(C»E 1 914.4 214.4 1280.0 700.0 1.577 1.491 2 914.0 214.0 1282.0 700.0 1.578 1.496 3 914.4 212.4 1280.0 702.0 1.577 1.491 4 914.8 214.8 1278.0 700.0 1.577 1.488 5 914.4 216.4 1280.0 698.0 1.577 1.492 6 914.2 214.2 1281.0 700.0 1.577 1.493 7 914.4 213.4 1280.0 701.0 1.577 1.491 8 914.6 214.6 1279.0 700.0 1.577 1.489 9 914.4 215.4 1280.0 699.0 1.577 1.491 10 914.2 213.2 1281.0 701.0 1.577 1.493 11 914.6 213.6 1279.0 701.0 1.577 1.489 12 914.6 215.6 1279.0 699.0 1.577 1.490 13 914.2 215.2 1281.0 699.0 1.577 1.494 S. MINIMUM= 1.577 FOR THE CIRCLE OF CENTER (1280.0, 700.0) ****************** * STABRG * ****************** 762.5 810.0 857.5 UJ z Q cr o 905.0 o >- 952.5 1000.0 980.0 1075.0 1170.0 X COORDINATE 1265.0 1360.0 •r mr MT BP V ********************************************* * * * SLOPE STABILITY ANALYSIS * * * ************** s T A B R G ***************** * * * PORTIONS (C) COPYRIGHT 1985, 1986 * * * * * * GEOSOFT ALL RIGHTS RESERVED * * * * * ********************************************* ESIDENTIAL SUBDIVISION, SCS&T 8921145, SECTION B, TRIAL C, 145BC ONTROL DATA NUMBER OF SPECIFIED CENTERS 0 NUMBER OF DEPTH LIMITING TANGENTS 0 NUMBER OF VERTICAL SECTIONS 15 NUMBER OF SOIL LAYER BOUNDARIES 4 NUMBER OF PORE PRESSURE LINES 0 NUMBER OF POINTS DEFINING COHESION PROFILE 0 )EISMIC COEFFICIENT S1,S2 = .00 .00 4 SEARCH STARTS AT CENTER (1270.0, 570.0),WITH FINAL GRID OF 1.0 ALL CIRCLES PASS THROUGH THE POINT (1375.0, 909.0) i GEOMETRY JjsECTIONS 1000.01094.01138.01142.01142.51182.01190.01233.01233.51273.01273.51333 T. CRACKS 830.0 830.0 860.0 861.0 866.0 871.0 876.0 876.0 882.0 882.0 888.0 893 «W IN CRACK 830.0 830.0 860.0 861.0 866.0 871.0 876.0 876.0 882.0 882.0 888.0 893 BOUNDARY 1 830.0 830.0 860.0 861.0 866.0 871.0 876.0 876.0 882.0 882.0 888.0 893 BOUNDARY 2 847.0 856.0 860.0 861.0 866.0 871.0 876.0 876.0 882.0 882.0 888.0 893 (BOUNDARY 3 876.0 876.0 876.0 876.0 876.0 876.0 876.0 876.0 882.0 882.0 888.0 893 BOUNDARY 41040.01040.01040.01040.01040.01040.01040.01040.01040.01040.01040.01040 • SOIL PROPERTIES LAYER I 1 2 . 3 COHESION FRICTION ANGLE 100.0 500.0 300.0 20.0 38.0 25.0 DENSITY 120.0 140.0 125.0 NUMBER TANGENT RADIUS (X) CENTER (Y) CENTER FS(BISHOP) FS(OMS) 1 2 1 924.9 924.3 354.9 354.3 1270.0 1272.0 1 OTn n 570.0 570.0 2.679 2.680 o cno 2.530 2.533 o coo 924.8 924.6 356.8 354.6 1270.0 1271.0 568.0 570.0 2 .679 2.679 2.531 2.531 7 924.9 353.9 1270.0 571.0 2.679 2.529 8 925.2 355.2 1269.0 570.0 2.679 2 .529 9 925.2 354 .2 1269 . 0 571.0 2.679 2.528 10 924.9 353.9 1270.0 571.0 2.679 2.529 11 925.3 353.3 1269 .0 572.0 2.679 2.528 12 925.0 353.0 1270.0 572.0 2.679 2.529 13 925.3 352.3 1269.0 573.0 2.679 2.527 14 925.6 353.6 1268.0 572.0 2 .679 2 .527 15 925.0 352.0 1270.0 573.0 2.679 2 .528 16 925.6 352.6 1268.0 573.0 2.679 2.526 17 925.5 354.5 1268.0 571.0 2 .679 2.527 18 924.9 353.9 1270.0 571.0 2.679 2 .529 S. MINIMUM= 2.679 FOR THE CIRCLE OF CENTER (1269. 0, 572.0) ****************** * STABRG * ****************** ii m m 765.0 _ 820.0 _ 875.0 UJ 2 Q Ql o 930.0 o >- 985.0 1040.0 1000.0 1110.0 1220.0 X COORDINATE 1330.0 1440.0 m i i i i APPENDIX B SOUTHERN CALIFORNIA SOIL & TESTING, INC. PROPOSED RESnKNTIAL SUBDIVISICN, LA OMJNA PLflCE, CARLSBAD RBOCMMENCED GRADING SPECIFICATIONS - GENERAL PROVISIONS QENERAL TNTENT The intent of these specifications is to establish procedures for clearing, compacting natural ground, preparing areas to be filled, and placing and conpacting fill soils to the lines and grades shown on the accepted plans. The recommendations contained in the preliminary geotechnical investigation report and/or the attached Specieil Pjxivisions are a part of the Recommended Grading Specifications and shall supersede the provisions contained hereinafter in t:he case of conflict. These specifications shall only be used in conjunction with the geotechnical report for which they are a part. No deviation from these specifications will be allowed, except where specified in the geotechnical report or in other written comnunication signed by the Geotechnical Engineer. GBSERSOCriGN AND TESTING Southern California Soil and Testing, Inc., shall be retained as the Geotechnical Engineer to observe and test t:he earthwork in accordance with tJiese specifications. It will be necessary that the Geotechnical Engineer or his representative provide adequate observation so that he may provide his opinion as to whetJier or not the vrork was acconplished as specified. It shall be the responsibility of the contractor to assist the Geotechnical Engineer and to keep him appraised 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 geotechnical report are encountered during the grading operations, the Geotechnical Engineer shall be contacted for further reconmendations, (R-9/89) Pi n i i I I I I SCS&T 8921145 October 11, 1989 Appendix B, Page 2 If, in the opinion of the Geotechnical Engineer, substandard conditions are encountered, such as questionable or imsuitable soil, unacceptable moisture content, inadequate conpaction, adverse weather, etc.; constmction should be stopped until the conditions are remedied or corrected or he shall recontnend rejection of tJiis vrork. Tests used to determine the degree of conpaction should be performed in accordance with the following American Society for Testing and Materials test metJiods: Maximum Density & Optimum Moisture Content - ASTM D-1557-78. Density of Soil In-Place - ASTM D-1556-64 or ASTM D-2922. All densities shall be expressed in terms of Relative Conpaction as detemuned by the foregoing ASTM testing procedures. PREPARATION OF AREAS TO RECEIVE FILL All vegetation, bmsh 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 appearance, free from unsightly debris. After clearing or benching the natural ground, the areas to be filled shall be scarified to a dept:h of 6 inches, brought to the proper moisture content, conpacted and tested for the specified minimum degree of conpaction. All loose soils in excess of 6 inches thick should be removed to firm naturcil ground vM.ch is defined as natural soils vM.ch possesses an in-situ density of at least 90% of its ntiximum dry density. (R-9/89) am SCS&T 8921145 October 11, 1989 i^pendix B, Page 3 4 When the slope of the natural ground receiving fill exceeds 20% (5 horizontial units to 1 vertical unit), the original ground shedl be stepped or benched. Benches shall be cut to a firm competent fomationsd soils. The lower bench shall be at least 10 feet wide or 1-1/2 times the the equipment width v^chever is greater and shall be sloped back into the hillside at a gradient of not less than tvro (2) percent. All other benches should be at least 6 feet wide. The horizontal portion of each bench shall be conpacted prior to receiving fill as specified herein for conpacted natural ground. Ground slopes flatter than 20% shall be benched vihen considered necessary by the Geotechnical Engineer. Any abandoned buried stmctures encountered during grading operations must be totally removed. All undergroxind utilities to be abandoned beneatJi any proposed stmcture should be removed from witJiin 10 feet of the stmcture and properly capped off. The resulting depressions from the above described procedures should be backfilled vd.t:h acceptable soil that is conpacted tx> the requirementis of the Geotechnical Engineer. This includes, but is not limited to, septic tanks, fuel tanks, sevrer lines or leach lines, storm drains and water lines. Any buried stmctures or utilities not to be abandoned should be brought to the attention of t±e Geotechnical Engineer so that he nay determine if any specicd recomnnendation will be necessary. All water veils viiich will be abanctoned should be h>ackfilled and capped in accordance to the requirements set forth by the Geotechnical Engineer. 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 l:ype of cap will depend on the diameter of the well and should be determined by the Geotechnical Engineer and/or a qualified Stmctural Engineer. (R-9/89) PI SCS&T 8921145 October 11, 1989 i^pendix B, Page 4 Fme MMERIAL Materials to be placed in the fill shall be aj^roved by the Geotechnical Engineer and shall be free of vegetable matter and other deleterious substances. Granular soil shall contiain sufficient fine material to fill the voids. The definition and disposition of oversized roclcs and ej^ansive or detximent:al soils are covered in the geotechnical report or Special Provisions. Expansive soils, soils of poor gradation, or soils wi1:h low strength characteristics may be tJioroughly mixed \fi.th ol±er soils to provide satisfactory fill material, but only with the explicit consent of the Geotechnical Engineer. Any inport material shall be approved by the Geotechnical Engineer before being brought to the site. PLACING AND CXWPACTION OF FILL i^roved fill material shall be placed in areas prepared to receive fill in layers not to exceed 6 inches in conpacted thickness. Each layer shall have a uniform moistvure content in the range that will allow the conpaction effort to be efficiently applied to achieve the specified degree of conpaction. Each layer shall be uniformly compacted to the specified minimum degree of conpaction with equipnient of adequate size to econcmdcally conpact the layer. Conpaction equipnent shoxild either be specificcilly designed for soil conpaction or of proven reliability- The minimum degree of conpaction to be achieved is specified in either the Special Provisions or the recommendations contained in the preliminary geotechnical investigation report. When the stmctural fill naterial includes rocks, no ixcks will be allov^ to nest and all voids must be carefully filled witJi soil such that the minimum degree of conpaction recommended in the Special Provisions is achieved. The maximum size and spacing of rock permitted in stmctural fills and in non-stxuctural fills is discussed in the geotechnical report, vAien applicable. (R-9/89) SCS&T 8921145 October 11, 1989 i^pendix B, Page 5 Field observation and conpaction tests to estimate the degree of conpaction of the fill will be taken by the Geotechnical Engineer or his representative. The location and frequency of the tests shall be at the Geotechnical Engineer's discretion. When the conpaction test indicates that a particular layer is at less than the required degree of conpaction, the layer shall be reworked to the satisfaction of the Geotechnical Engineer and until the desired relative conpaction has been obtained. Fill slopes shall be conpacted by means of sheepsfoot rollers or other suitable equipnent. Conpaction by sheepsfoot rollers shall be at vertical intervals of not greater than four feet. In addition, fill slopes at a ratio of two horizont:al to one vertical or flatter, should be t:rackrolled. Steeper fill slopes shall be over-built and cut-back to finish contours after the slope has been constmcted. Slope conpaction operations shall result in all fill material six or more inches inward from the finished face of the slope having a relative conpaction of at least 90% of maximum dry density or the degree of coipaction specified in the Special Provisions section of this specification. The cotpaction operation on the slopes shall be continued until the Geotechnical Engineer is of the opinion that the slopes will be stable surficially stable. m m Density test:s in tJie slopes will be made by the Geotechnical Engineer during constmction of the slopes to detemdne if the required cotpaction is being achieved. Where failing tests occur or other field problons arise, the Contractor will be notified that day of such conditions by written communication from the Geotechnical Engineer or his representative in the form of a daily field report. If the nethod of achieving the rec[uired slope conpaction selected by the Contractor fails to produce the necessary results, the Contractor shall rework or rebuild such slopes until the required degree of conpaction is obtained, at no cost to the Owner or Geotechnical Engineer. (R-9/89) SCS&T 8921145 October 11, 1989 Appendix B, Page 6 CUT SLOPES The Engineering Geologist shall inspect cut slopes excavated in rock or litJiified formational material diuring the grading operations at intervals determined at his discretion. If any conditions not cinticipated in the preliminary report such as perched water, seepage, lenticular or confined stxata 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 Engineer to determine if mitigating measures are necessary. Unless otJierwise specified in the geotechnical report, no cut slopes shall be excavated higher or steeper than that allowed by the ordinances of the controlling govemmental agency. ENGMEERING GBSERVATIGN Field observation by the Geotechnical Engineer or his representative shall be made during the filling and conpacting operations so that he Ccin express his opinion regarding the conformance of the grading with acceptable standards of practice. Neit±.er the presence of the Geotechnical Engineer or his representative or the observation and testing shall not release the Grading Contractor from his duty to conpact all fill material to the specified degree of conpaction. SEASCN LIMITS Fill shall not be placed during unfavorable weather conditions. When work is intermpted by heavy rain, filling operations shall not be resvmied 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 vrork. (R-9/89) SCS&T 8921145 October 11, 1989 i^pendix B, Page 7 RECGMMENOED GRADING SPECIFICATICNS - SPECIAL PROVISIGNS RELKTIVE COMPACTION: The minimum degree of conpaction to be ob1:ained in conpacted natxural ground, conpacted fill, and conpacted backfill shall be at least 90 percent. For street and parking lot subgrade, the upper six inches should be conpacted to at least 95% relative conpaction. EXPAierVE SOUS: Detrimentally e^qpansive soil is defined as clayey soil vjhich has an e:q)ansion index of 50 or greater vihen tested in accordance with the Uniform Building Code Standard 29-C. OVERSIZED MAOERIAL: Oversized fill naterial is generally defined herein as rocks or lunps of soil over 6 inches in diameter. Oversize materials should not be placed in fill unless recomnendations of placement of such material is provided by the geotechnical engineer. At least 40 percent of the fill soils shall pass through a No. 4 U.S. Standard Sieve. TRANSmCN IDISs Where transitions between cut and fill occur witihin the proposed building pad, the cut portion should be undercut a minimum of one foot below the base of the proposed footings and reconpacted as stmctural backfill. In certain cases that would be addressed in the geotechnical report, special footing reinforcement or a combination of special footing reinforcement and undercutting may be required. (R-9/89)