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Home My WebLink About3557; Calavera Hills Phase II Bridge Retaining Walls; Calavera Hills Phase II Bridge Retaining Walls; 2001-03-05I I pGRaup DELTA Ccrtijhi MBE •Ny,;n.J..x:/ .H»,ir.:r;/.\-s March 5, 2001 Simon Wong Engineering 9968 Hilbert Street, Suite 202 San Diego, CA 92131 Attention: Subject: Mr. Mark Graveling Recommended Geotechnical Parameters Carisbad Boulevard Overhead (Bridge No. 57C-134) Seismic Retrofit Project San Diego County, Califomia Group Delta Project No. 1-147 Dear Mark- In response to your request, we are pleased to provide you our recommendations regarding the seismic reti-ofit design of the existing Carisbad Boulevard Overhead Bridge. The bridge is located along Carisbad Boulevard approximately 0.6 mile northwesteriy of Elm Avenue (see Rgure 1). Review of E^dsting Data We have reviewed the Preliminary Geotechnical Report dated May 23, 1997 and the Uquefaction Report dated August 12, 1997 prepared by Group Delta Consultants (GDC) as part of the Local Agency Seismic Retrofit Project. There was no Log of Test Borings (LOTB) available for the bridge. GDC performed two hollow-stem auger borings (BH-l and BH-2) on June 6, 1997 to investigate liquefaction potential at the bridge site. The boring logs and laboratory test data are provided in Appendix A. The Boring Location Plan is shown in Figure A-1 in Appendix A. Subsurface Cbnditionis Based on the results of field investigation by GDC, soils at the bridge site consist mostly of clayey sand to sandy clay (SC/CL) fill soils, overlying terrace deposits consisting of dense to very dense silty to clayey sands (SM/SC) and poorly graded sand (SP). A clayey sandstone bedrock (Santiago Formation) was encountered below the fill and terrace deposits at about El. +24 ft in boring BH-l and El. +14 ft in boring BH-2. A soil cross-section below the bridge is shown in Figure 2 Groundwater was not encountered in boring BH-l. A perched groundwater was encountered in boring BH-2 at El. +14.5 feet. 92 Ar;.u?iuit!t Snii.- I 2i! A .•\ii.'ici Vieiti, C.ilifarni.i 9^l^^6-412l A ('H9) IiM-] (i20 voice A C-W-n i^{)9-][)?<) fax- C.ii:ior;ii,: A (3iiij 3:0-3 ii);i S,in liii-i^u. (>ii;nmM A iS5S! 373-.:-7/ A Recommended Geotechnical Parameters Carisbad Blvd. Overhead Simon Wong Engineering GDC Project No. 1-147 Recommended Soil Parameters April 5, 2001 Page 2 At your request we are providing soil parameters for each major sol! type encountered. The soil parameters include unit weight (y), friction angle ((j)), cohesion (c), soil m.odiilus (k), and strain at 50% of ultimate stress (B^). In addition, we are also providing ultimate and allowable bearing capacities and coefficient of friction. The recommended geotechnical parameters are summarized in Table 1. References Group Delta Consultants, 1997, "Preliminary Geotechnical Report, Local Agency Seismic Retiofit Project, Bridge No. 57C-134, Carlsbad Overhead, San Diego County, California," prepared for Moffatt & Nichol Engineers, dated May 23, 1997. Group'Delta Consultants, 1997, "Uquefaction Report, Carisbad Overhead, Bridge No. 57C-134, Local Agency Seismic Retrofit Project, San Diego County, California," prepared for Moffatt & Nichol Engineers, dated August 12, 1997. Attachments The following table, figures and appendix are attached and complete this letter report: Table 1 Summary of Recommended Geotechnical Parameters Figure 1 Site Location Map Figure 2 Soil Cross Section Appendix A Existing Geotechnical Data GROUP! ^ [DELTA: n47-Rercommende<} Geotechnical Parameters.doc Recommended Qeotechnical Parameters /^^p^jj 5 20OI Carlsbad: Blvd. Overhead p'^ ^ ^ Simon Wong Engineering GDC Project No. i-I47 We hope this report meets your immediate needs. We appreciate the opportunity to assist you in this important project. If you have any questions, please call us at (949) 609-1020. . Very truly yours, GROGP DELTA CONSGLTANTS, INC. Carlos V. TMiiinte, P.E. Project Engineer ^ Kul Bhushan, Ph.D., G.E. President ^ IGROUP DELTA. n 47-Rercommended Geoteclmical Parameters.doc TABLES GROUP DELTA TABLE 1 SUMMARY OF RECOiVWENDED GEOTECHNICAL PARAMETERS CARLSBAD BOULEVARD OVpRHIiAD (BRIDGE NO. 57C-134) SEISMIC RETROFIT PROJECT Soil Type Y (psf) (deg.) c (psf) k (pci) 1 Clltimate Bearing Capacity (ksO Allowable Bearing Capacity (ksf) Friction Coefficient Fill 120 0-2,000 500 0.01 10 3 0.35 Terrace Deposits 125 38 0 225 N/A 25 5 0.50 bedrock 130 0 5,000 2,000 0,005 25 5 0,50 FIGURES 1 VV\V--'^_n i - Army and N^l^^j^(^. «, \ Acflderii/ Vfc-^^=A- CARLSBAD: o «4 The Base Map is from the USGS 7.5 niinute San Luis Rey, Califomia Quadrangle, 1968, Photorevised 1975 A Approx. Scale 1:24000 GROUP DELTA, PRO JEGT NO. I-147 Site Location Map Carlsbad Overhead FIGURE 1 - ' ^ < i: APPEmiXA EXISTING GEOTECHNICAL DATA APPENDIXA A.I Introduction The strbsurface conditions at the project site were investigated by Group Delta ConsultaMs on June 6, 1997 by performing two soil borings shown in Figure A-lf Boring Location Plan. A summary of tiie soil borings is presented in Table A-1. The results of held investigation and laboratory testing are summarized in Table A-2. A.2 Field Investigation The borings were advanced utilizing a CME 95 hollow-stem driU rig. The borings had a hole diameter of about 8 inches. ITie borings were perfonned by West Hazmat Company under a continuous techmcal supervision of a Group Delta representative, who visually b I'^'rT'?'''-,"''^'''^^'^ ^^^^^^'^ «f the borings, interpreted starigraphy elasstfied tiie soils, and obtained split-spoon Standard Penetration Test (SPT) samples at 5 ft interval. The soils were classified in tiie field and fiirther examined in the laboratory m accordance witii tiie Unified Soil Classification System (Figure A-3) results ^^'^ "^^''^ neeessaiy, on lhe basis of laboratory test Soil samples were obtained using Standard Penetration Tests which were performed in aeeordance wttii ASTM D1586-82 using a 2-ineh outside diameter and 1.37lineSde diameter spiit-spoon barrel sampler. The SPT sampler was driven witii a 140-pound safety hammer dropping 30 inches. ^ The Standard Perietration Test consists of counting tiie number of hammer blows it takes o dnve tiie sampler 1 foot into the ground. SPT bloweounts are often used as an index of tiie relative density and resistance of tiie sampled materials. A.3 Laboratory Testing Soil samples were earefully sealed in tiie field to prevent moisture loss. All tiie samples were tiien transported to our laboratory for examination and testing. Tests were performed on selected samples as an aid in classifying tiie soils and to evaluate tiieir physical properties and engineenng characteristics. All tests were performed in general accordance witii appropnate Caltrans Testmg Metiiods (CTM). Brief descriptions of tiie laboratoiy testing program and test resuhs are presented below. A.3.1 Soil Classification The subsurface materials were classified using tiie Unified Soil Classification System in accordance witii ASTM Test Metiiods D2487-85 and D2488-84. Tlie soil cIassLati;ns are presented on tiie boring logs in Appendix A and summarized in Table A-2. A3.2 In Situ Moisture Content Moisture content and dry densify were detemiined for selected samples The drive 'ZtcZloT'Z'^f obtain volume and wet weight then were dried in accordance with CTM 226. After diymg, the weight of each sample was measured, and moisture content and dry density were calculated. The moisture content of selected SPT samples and bu k samples were also determined. Moisture content values are presented on the bonng logs in Appendix A and summarized in Table A-2. A.3.3 Grain Size Distribution and Wash Analysis Representative samples were dried, weighed, soaked in water until individual soil particles were separated, and then washed ori tiie #200 sieve. The portion ofthe material ret^ned on tiie ^200 sieve was oven-dried and tiien run through a sLdard set of s" ves m acconiance witii CTM 202. The results of grain size distribution tests performed a^e graphically shown m Figure A-2. The relative proportion (or percentage) by weight of Table A-2 The percentage of fines (i.e., soil passing #200 sieve) is an important factor for eyduating tiie hquefaction potential of sandy soils. Fines content were detemiined for seiecteo sandy soil samples which mav liotiefv. Thp A.4 Boring Logs Detailed logs of tiie soil borings including blowcount data and in situ moisture content and dry densities are presented in Figures A-4 through A-5. Laboratoiy tests perfomied other tiian tiie moisture content and dry densify detennination are shown on the bonng logs in tiie column "Otiier Tests". The following abbreviations are used on tiie logs to indicate the fype of test performed. ^ GS Grain Size Distribution Test WA Wash Anafysis / Fines Content Determination (% Passing #200 Sieve) A.5 List of Attached Tables and Figures The following tables and figures are attached and complete this appendix: ™eA-l Soil Boring Summaiy ^^^^^ ^''^ Summary of Field and Laboratory Test Results ^ig^e A-1 Boring Location Plan Figure A-2 Gram Size Distribution Figure A-3 Key for Soti Classification Figures A-4 through A-6 Boring Logs (BH-1 through BH-2) TABLE A-1 SOIL BORING SUMMARY CARLSBAD OVERHEAD (BRIDGE NO. 570-134) LOCAL AGENCY SEISMIC RETROFIT PROJECT Boring Station Offset firom" Surface Total Groundwater Associated Excavation No. No. Centerhne Elevation Depth Depth Foundation Equipment (ft) (ft) (ft) (ft) Support BH-I 477+70 28.0 LT-49,0 30.5 * Bent 6 CME 75 BH-2 Note*;- 480+13 48.7 LT 39,0 46,0 24,5 ** Bent 1 CME 75 * Groundwater not encountered ** Perched groundwater encountered Boring No. BH-I TABLE A-2 SUMMARY OF FIELD AND LABORATORY TEST RESULTS CARLSBAD OVERHEAD (BRIDGE NO. 57C-134) LOCAL AGENCY SEISMIC RETROFIT PROJECT Sample Depth (ft) 5-6.5 io-n.5 15-16.5 USCS Soil Type CL CL Equiv. SPT Blowcount (blows/ft) 16 26 Moisture Content (%) SC 20-21.5 25-26.5 30-30.5 SC SC SC 33 16 >iOO > 100 18.3 10.7 Dry Density (pcf) 109.6 10.5 9.8 11.1 Gravel Content Sand. Content (%) 120.4 FLnes Content (%) 33.8 21.5 Liquid Limit Plastic Limit (%) 5-6.5 SC 10-11.5 SM/SC 15-16.5 SM/SC 20-21.5 SP 25-26.5 SC 30-31.5 SC 35-36.5 SC 40-41.5 SC 45-46 * SC Note: * No sample recovery 32 37 45 86 73 71 71 87 6.3 5.7 5.6 8.0 6.9 11.0 12.7 li.I 76.5 90.1 29; 1 23.4 16.0 9.9 19.6 30.5 ws'-oh't Mntl Sint -I- Bsnf B ELEVATION PLAN I' •• 50' • PROJECTNO, I-l 11 Group Delta Consultants CARLSBAD OVERHEAD, BRIDGE NO. 57C-134 (SAN DIEGO COUNTY, CALIFORNIA) BORING LOCATION PLAN (REFERENCE: GENERAL PLAN, CARLSB/\D BOULEVARD OVERHEAD) BH-l Figure A-I C\PRO;ECrSWiOFFATnRETROm\J7C134BP.GRF UNIFIED SOIL CLASSIFICATION COBBLES GRAVEL SAND SILT OR CLAY COBBLES COARSE RNE COARSE] MEDIUM FINE SILT OR CLAY vs. SIEVE SIZE m INCHES U.S. STANDARD SIEVE No. HYDROMETER ° ^ 1/23/8 * 10 20 40 60 140 200 SYMBOL BORING O BH-2 O 8H-2 GRAIN SIZE IN MILLIMETER DEPTH LL 10-11.5 20-21.5 fLL DESCRIPTION SM/SC SP Remark : Project No. I-111 GROUP DELTA CONSULTANTS, INC. CARLSBAD OVERHEAD GRAIN SIZE DISTRIBUTION Figure NO. A-S Pl miARYDlVISl ONS GHOUP SYMBOL SECONDARY DIVISIONS tn s| 1 fc J2 C> cr e *H <- o o O 5 o CLEAN GRAVELS (Loss Thsn 5% Flnm) GW Well Graded Gravels, Gravala WJh Sand, Utlo Or No Fines. tn s| 1 fc J2 C> cr e *H <- o o O 5 o CLEAN GRAVELS (Loss Thsn 5% Flnm) GP Pooriy Graded Gravels, Gravels With Sejvi, UUa Or No Fines. tn s| 1 fc J2 C> cr e *H <- o o O 5 o GRAVEL (Mom Than 12% Fines} GM SatyGravoIs.SUty Gravel Wilh Sand, Non Plastic Fines. . tn s| 1 fc J2 C> cr e *H <- o o O 5 o GRAVEL (Mom Than 12% Fines} GC Clayey Gravels, Clayey Gravel WlUi Sand, Ptaslk: Fines, tn s| 1 fc J2 C> cr e *H <- o o O E c z § ,C - '3 <e »*^ Ir Ct£AN SANDS {Less Than 5% Fines) SW Well Graded Sands. Sand Wilh Gravel, Ulle Or No Fines. tn s| 1 fc J2 C> cr e *H <- o o O E c z § ,C - '3 <e »*^ Ir Ct£AN SANDS {Less Than 5% Fines) SP Poorly Graded Sands. Dtlle Or No Fines. tn s| 1 fc J2 C> cr e *H <- o o O E c z § ,C - '3 <e »*^ Ir SANDS (Mow Than 12% Fines) SM smy Sonds. Sand-SUl MMufes. NorvPIasllo Fhea, tn s| 1 fc J2 C> cr e *H <- o o O E c z § ,C - '3 <e »*^ Ir SANDS (Mow Than 12% Fines) ac Clayey Sands, Sand-Clay MMures. Plastic Fines. — « O 15 t- S Q Q P o ^ Q SILTS AND CLAYS; Uquid Umit Is Less Than 50 ML InorsaricSlllaandVery Fine Sands, Rock Flour, S«y or Clayey Fine Sands or • Clayay Sffls Wnh SllqW Plaslldty. — « O 15 t- S Q Q P o ^ Q SILTS AND CLAYS; Uquid Umit Is Less Than 50 CL Inorganic Clays o( Lo w lo Medium PlasUclty, Gravelly Clays, Sandy Clays, Silly Clays, Lean Clays. — « O 15 t- S Q Q P o ^ Q SILTS AND CLAYS; Uquid Umit Is Less Than 50 OL Organic Sito and Organic SfHy Clays ol Low PlasUdly. — « O 15 t- S Q Q P o ^ Q SILTS AND CLAYS MH Inorganic Basllo Silts, Micaceous or Dtamaceous FlrM Sandy orSBty Soils. Plastic Slits. — « O 15 t- S Q Q P o ^ Q SILTS AND CLAYS \h CH Inorganic Clays or High Plasticity, Fai Clays, — « O 15 t- S Q Q P o ^ Q SILTS AND CLAYS 1 OH Oraanlc Clays of Medium lo High Plasticity. Oiyante Sills. • HIGHLY ORGANIC SOILS ' PT Peal and OlherHigWy OraanScSoils. Dual Group Symbda Are Used For Coarse Grained Soils Wim S% To 12% Rne3 (Passing #200 Sieve) Ar^ Boidariina ClaasJficalion May Be Represented Wilh Two Symbols Separated By A Slash. 'Number of Blows of 140 Pound Hammer Failing 30 Inches To DnVa a 2-irich O.D. (1-3/8 Inch I.D.) Split Barrel Sampler (ASTM D-1586 Standard Penelralion test). GRANULAR COHESIVE Cphsistency Blows4^oot* Consistency BIowaFoot' Strength" Very Looso 0-4 Very Soft 0-4 0-1/2 Loose 5-9 Soft 5-9 • 1/2-1 Slightly Conpact 10-19 Stiff 10-19 1-2 Compact 20-34 Very Stiff 20-34 2-4 Dense 35-69 Hard 35-59 Over 4 Very Dense >70 Very Hard >70 - "Shear Slranglh In KSF. Head From Pocket Penelromater. CLASSIFICATION CRiTERlA BASED ON LAB TEST S PLASTICITY CHART 60 40 •H 20 1 1 / r C -on V / 0 9 M ^or OH ML 1 OfOL CLAYS AND SILTS SANO GRAVEL COBBLES BOULDERS CLAYS AND SILTS Fine Medium Coarse Fine Coarse COBBLES BOULDERS Sieve Sizes 200 40 10 4 3/4" 3- 12* U.S. STANDARD SERIES SIEVE CLEAR SQUARE SIEVE OPENINGS Classificalion ol Earth Materials is. Based on Reld Inspection and Should Not Be Constated To Imply Laboratoiy Analysis Unless So Slated. ^ ... . - Den . (D- GWandSW: Cu= -^^GreaterThan4ForGWand6ForSW; C< 10 Between 1 and 3 20 40 60 Liquid Limit (LL) 80 100 GP and SP: Clean Gravel or Sand Not MeeU'ng Rsquirement For GW and SW. GM and SM: Atterberg Limit Below 'A' Une or P.I. Less Than 4. GC and SC: Altarberg Limit Above "A" Line P.I. Greater Than 7. KEY FOR SOIL CLASSIFICATION FIGURE A-3 w X o o >- Q WA WA 18.3 .O CQ 16 109.6 10.7 10.5 9.8 11.1 26 DESCRIPTION OF SUBSURFACE MATERIALS D 33 120.4 16 >100 >100 ?^lfiSl"1-'"'"' "'^^^^ "'^'•^ *T LOCATION OF THIS BORrNG AND AT THE fliSFBT^ AT ™^cf, onifj;'.'''"^ CONDITIONS MAY DIFFER AT OTHER LOCATIONS AND MAY CHANOE 10- SAMPLE TYPES: [C] Rock Core \S} Standard Split Spoon [D] Drive Sample [B] Bulk Sample pf] Tube Sample • 35- FillT ^ Clayey SAND (SC), brown, damp, loose to slightly compact Sandy CLAY (CL), brown gray, moist, stiff to very stiff, with trace of gravel No sample recovery •40 Clayey SAND (SC); brown, moist, slightly compact to compact Sand lens Gravels and cobbles 35 30 Santiago Formation: Clayey SANDSTONE (SC), light gray, moist, very dense Harder drilling \Auger refusal^ Boring terminated at Elev. 18.5 ft Groundwater not encountered 25 20 DATE DRILLED: 6-6-97 EQUIPMENT/METHOD USED CME 95/HSA SUPERVISOR: G. SPAULDING PROJECT NO. 1-11 1 CARLSBAD OVERHEAD SAN DIEGO COUNTY, CALIFORNIA 15 10 LOG OF BORING NO. BH- 1 PAGE 1 OF 1 FIGURE A-4 DESCRIPTION OF SUBSURFACE MATERIALS AT THiS LOCATION vJ™ THE PA«AG^OF nME THP nT.T^f '^'^^ OF ACTUAL CONDITIONS ENCOU^TCRED RESENTED IS A SIMPLIFICATION Terrace Depnsjiv ' Clayey SAND (SC), red brown, damp, compact to dense o i! w w 39 •35 Silly toCS3^rsAND(SM7SC); ~ mottled brown/gray/red, damp, dense 30 Poorly Grad^"SANDwitIi Silt (§P)~ brown, damp, very dense -25 •20 Perched groundwater at Elev. 14.5 ft Santiago Formation: Clayey SANDSTONE (SC), light olive gray, moist, very dense 15 10 -5 SAMPLE TYPES [C] Rock Core |S] Standard Split Spoon [D] Drive Sarriple [B] Bulk Sample ff] Tube Sample DATE DRILLED: 6-6-97 EQUIPMENT/METHOD USED- CME 95/HSA SUPERVISOR: G. SPAULDING GROUP PROJECTNO. I-m CARLSBAD OVERHEAD _j^NDlEGOCOUNTY, CALIFORMA LOG OF BORING NO. BH- PAGE 1 OF 2 FIGURE ,A-: Di m o 11.1 OD >< Q CO O <t; la 1-1 71 87 40- A? Z'LOCS W,™ ^rSoE OF TIM^THF^T" ANO^MAf CHLGE OF ACTUAL C0NJ;T10N™ ENCOUNTERED '^'^ ^ SIMPLIFICATION DESCRIPTION OF SUBSURFACE MATERIALS 45^ 50- 55- 60-1 65- 70- "\Auger refusal Boring terminated at Elev. -7 ft ' Perched groundwater encountered at Elev. 14,5 ft -10 -15 -25 SAMPLE TYPES: [C] Rock Core [S] Standard Split Spoon [o] Drive Sample [8] Bulk Sample 1X1 Tube Sample 75- -30 -35 DATE DRILLED; 6-6-97 EQUIPMENT/METHOD USED- CME 95/HSA SUPERVISOR: G. SPAULDING PROJECTNO. 1-111 CARLSBAD OVERHEAD SAN DIEGO COUNTY, CALIFORNIA ^0 LOG OF BORING NO. BH- 2 , FIGURE A-6