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HomeMy WebLinkAboutSupplemental Subsurface Soils InvestigationLORSo GEOTECHNICAL GROUP, INC. Engineering A Geology A Environmental SUPPLEMENTAL SUBSURFACE SOILSAVESTIGATION SUMMIT AVENUE STORM DRAIN MPSD LINE B - PHASE III FONTANA AND RANCHO CUCAMONGA SAN BERNARDINO COUNTY, CALIFORNIA PROJECT NO.: 62047.13 OCTOBER 11, 2005 Prepared for: AEI -CASC Engineering 937 South Via Lata, Suite 500 Colton, California 92324 Attention: Mr. Ceazar Aguilar 6121 Quail Valley Court . Riverside, CA 92507 . (951) 653 -1760 • Fax (951) 653 -1741 �. L OR GEOTECHNICAL GROUP, INC. Soil Engineering A Geology A Environmental October 11, 2005 AEI -CASC Engineering Project No. 62047.13 937 South Via Lata, Suite 500 Colton, California 92324 Attention: Mr. Ceazar Aguilar Subject: Supplemental Subsurface Soils Investigation, Summit Avenue Storm Drain, MPSD Line B - Phase III, Cities of Fontana and Rancho Cucamonga, County of San Bernardino, California. Transmitted with this letter is our report entitled Supplemental Subsurface Soils Investigation, Summit Avenue Storm Drain, MPSD Line B - Phase III, in the cities of Fontana and Rancho Cucamonga, County of San Bernardino, California, Project No. 62047.13. This report was based upon a scope of services generally outlined in our proposal letter dated June 29, 2005 and other written and verbal communications with you. This report provides some additional geotechnical findings, conclusions, and recommendations based on the newly obtained data. It has been our pleasure assisting you on this project. If you have any questions or comments concerning the information in this report, please contact us. LOR Geotechnical Group, Inc. 6121 Quail Valley Court . Riverside, CA 92507 A (951) 653 -1760 A Fax (951) 653 -1741 Table of Contents Page No. INTRODUCTION ............... ..............................1 PROJECT DESCRIPTION ........ ............................... 2 FIELD INVESTIGATION ......... ............................... 2 9 LABORATORY TESTING PROGRAM . ............................... 3 FINDINGS ................... ............... •-- ••--- ... - - -.3 CONCLUSIONS ............... ..............................4 RECOMMENDATIONS ............. ............................5 Short -Term Excavations 5 Shoring Design Criteria .................................... 6 Preparation of the RCB Areas ...... .................. ........ 7 RCB Design .............. ..............................8 Engineered Compacted Fill ................................. 8 Preliminary Pavement Design ................................ 9 Sulfate Protection .............. ........ . ........ ....... 10 �. LIMITATIONS .............................................. 10 TIME LIMITATIONS ........... ............................... 11 CLOSURE--• ................ ........ .....................11 APPENDICES -° Appendix A - Index Map and Plat Appendix B - Field Investigation and Boring Logs Appendix C - Laboratory Testing Program and Results N �, LOR GEOTECHNICAL GROUP, INC. AEI -CASC Engineering Project No. 62047.13 October 11, 2005 INTRODUCTION During April of 2005, a Subsurface Soils Investigation was conducted by LOR Geotechnical Group, Inc., for Alternative A of the City of Fontana Storm Drain Alignment Study. This alternative involved the extension of the Summit Avenue Storm drain along East Frontage Road crossing the 1 -15 freeway and the re- alignment of the Hawker Crawford Channel. The new Hawker Crawford Channel was planned to start downstream of Beech Avenue and to proceed southerly along the northwest side of the 1 -15 freeway crossing Cherry Avenue to finally discharge into San Sevaine _• Basin No. 5. The purpose of this investigation was to evaluate the subsurface conditions encountered in our exploratory trenches and borings to provide geotechnical design recommendations for the proposed improvement. Since the time of this study, however, the City of Fontana has evaluated other options and is currently considering a new alignment. We understand that the new alignment, named Summit Avenue Storm Drain MPSD Line B - Phase III, will consist of the extension of the existing Summit Avenue drain along East Frontage Road turning south, instead of crossing the 1 -15 freeway. This alignment will run parallel to the 1 -15 freeway crossing under 1 -15 via Cherry Avenue. It will then run adjacent to 1 -15, west of Cherry Avenue, discharging into San Sevaine Basin No. 5. Therefore, during August and September of 2005, a supplemental Subsurface Soils Investigation was performed by this firm for the currently proposed alignment of the project. The aw- purpose of this study was to supplement our original subsurface soils report with more accurate geotechnical data obtained from the new alignment. The scope of our supplemental services included: • Drilling of four additional exploratory borings within the new alignment to �. evaluate the physical soil conditions pertinent to the proposed improvement within this area; • Laboratory testing of selected soil samples obtained during this supplemental investigation; • Development of additional geotechnical recommendations as needed for storm drain construction and design; and 1 LOR GEOTECHNICAL GROUP, INC. AEI -CASC Engineering Project No. 62047.13 October 11, 2005 • Preparation of this supplemental report summarizing our findings, conclusions, and recommendations for the subject improvement. The approximate location of the site, as it lies within its regional setting, is shown on the enclosed Index Map, Enclosure A -1, within Appendix A. PROJECT DESCRIPTION The newly proposed project alignment is illustrated in the 80 -scale Project Plans, Summit Avenue Storm Drain, MPSD Line B - Phase III, from Sevaine Basin No. 5 to west of San Sevaine Road, prepared by AEI -CASC Engineering, dated September 2005. A plan view of the alignment is presented in the enclosed Plat, Enclosure A -2, within Appendix A. As noted on this plat, in order to direct the flow of surface run -off from the region in the City of Fontana located off Summit Avenue and east of the 1 -15 freeway to the newly reconstructed San Sevaine Basin No. 5, the existing Summit Avenue drain will be continue to the south along East Frontage Road going under the 1 -15 freeway via Cherry Avenue. The alignment along Cherry Avenue will cross the west side of the road at a horizontal distance of approximately 9 to 10 feet from the spread footings of Bent 2 of Cherry Avenue Bridge. The drain is planned to be placed at about 7 to 9 feet below the embedment depth of Bent 2 Cherry Avenue Bridge spread footings. After crossing Cherry Avenue, the storm drain will then run along the west side of the 1 -15 freeway, west of Cherry Avenue, discharging into San Sevaine Basin No. 5. The Summit Avenue storm drain will consist of a single cell, cast -in- place, reinforced concrete box (RCB) to be placed at depths of about 14 to 25 feet below the existing ground surface. The RCB is anticipated to range in width from 12 to 16 feet and in height from 8 to 16 feet. Open excavations are anticipated to be used for most of the construction of the subject storm drain. FIELD INVESTIGATION x Our supplemental field exploration program was conducted on August 31, 2005 and consisted of drilling four exploratory borings with a truck - mounted CME 55 drill rig equipped with an 8 -inch diameter hollow stem auger. The borings were drilled to depths ranging from 20.5 feet to 31.5 feet below the existing ground surface. The _,,, LOR GEOTECHNICAL GROUP, INC. AEI -CASC Engineering Project No. 62047.13 October 11, 2005 approximate locations of our borings are presented on Enclosure A -2, within Appendix A. Logs of the subsurface conditions encountered in the exploratory borings were maintained by a staff geologist from this firm. Relatively undisturbed and bulk samples were obtained at a maximum depth interval of 5 feet and returned to the laboratory in sealed containers for further testing and evaluation. A detailed description of the field exploration program and the boring logs are presented within Appendix B. LABORATORY TESTING PROGRAM Selected soil samples obtained during the field investigation were subjected to laboratory testing to evaluate their physical and engineering properties. Laboratory testing included moisture content, dry density, compaction characteristics, direct shear, sand equivalent, and soluble sulfate content. A detailed description of the laboratory testing program and the test results are presented within Appendix C. FINDINGS Data from our recent borings concur with our original explorations that the project area is underlain by coarse grained alluvial materials. The alluvial materials noted in our borings were composed of well graded sands with gravel and lesser units of silty sands with occasional layers of sandy silts. These units contained variable amounts of gravel ranging from 5 to 25 percent and trace of cobbles. Due to the presence of these coarse -sized particles within the alluvium, all borings encountered difficult drilling conditions which slowed progress and increased wear on the drill equipment. Our recent boring B -3 met early refusal on cobbles and gravels at a depth of 8 feet and was moved 5 feet north from its original location in order to achieve the desired exploration depth of approximately 30 feet. The alluvial units tended to be brown to grayish brown in color, and dry to damp. Based on our in -place density determinations and equivalent Standard Penetration Test (SPT) data, it was found that the alluvial materials were generally in a medium dense to dense condition below depths of about 2 feet from the existing ground surface. 3 14 LOR GEOTECHNICAL GROUP, INC. AEI -CASC Engineering Project No. 62047.13 October 11, 2005 Neither bedrock nor groundwater was encountered in any of our exploratory borings. A more detailed description of the subsurface soil conditions, as encountered within our exploratory borings is presented on the attached Boring Logs within Appendix B. Based upon our field investigation and testing program, it is our opinion that the proposed improvement remains feasible from a geotechnical standpoint, provided the �. recommendations presented in the original Preliminary Soils Investigation report and this supplemental report are incorporated into design and implemented during construction. a As noted by our original and recent explorations at the site, the native materials should provide adequate support for the subject improvements within the project alignment. However, due to the clean and coarse grained composition of the native soils, caving of the site excavations should be anticipated. Thus, proper construction techniques such as safe sloped excavations and /or shored excavations should be •g used. Because the proposed drain improvements will be installed at a short horizontal distance from Cherry Avenue Bridge foundations and below the elevation of the footings, site excavations should be performed with caution in order not to impact the footing support. Our review of the structural plans of the bridge and plans of the storm drain indicate that open excavations for the drain placement adjacent to the bridge could range from 0.5:1 (horizontal:vertical) to 1:1 (horizontal:vertical) and from 7 to 10 feet in height. Engineering analysis of these geometries along with an allowable pressure of 12,000 pounds per square foot exerted by the bridge footings on the ground shows that the stability of these excavations would not be adequate. Thus, we recommend soil retention alternatives such as a soldier pile wall, intrusion grouting, or similar methods to be applied along this portion of the alignment to safeguard the bridge structure and construction of the drain. The site soils should provide adequate quality fill material, provided they are free from organic matter and other deleterious materials. However, they will require the removal of rocks or similar irreducible materials with a maximum dimension greater than 6 inches from the fills in order to facilitate the compaction of the fill and backfill 4 LOR GEOTECHNICAL GROUP, INC. W� AEI -CASC Engineering Project No. 62047.13 a October 11, 2005 and /or construction of the proposed RCB drain. The site soils were encountered to be .� relatively dry to damp and therefore they will require some moisture conditioning in order to achieve the desired optimum moisture content prior to their usage as backf ill and fill. The subsurface conditions encountered in our exploratory borings are indicative of the locations explored. They are not to be construed that these conditions are present the same throughout the project alignment. �w RECOMMENDATIONS Short -Term Excavations Standard trenching equipment should be suitable for the proposed excavations at the RCB locations. Excavation safety and precautions, including safe slope excavation inclinations, should be implemented and are the responsibility of the contractor. Following the California Occupational Safety and Health Act (CAL -OSHA) requirements, excavations deeper than 5 feet should be sloped or shored. All excavations and shoring should conform to CAL -OSHA requirements, unless a Registered Professional Engineer provides alternative short term slopes based on a site- specific analysis (Section 1541.1). Short -term excavation greater than 5 -feet deep shall conform to Title 8 of the California Code of Regulations, Construction Safety Orders, Section 1504 and 1539 through 1547. Based on our exploratory borings, it appears that Type C soil is the predominant type of soil on the project and all short -term excavations should be --� based on this type of soil. In accordance to Title 8 of the California Code of Regulations, all simple slope excavations up to 20 feet in depth made in Type C soil should have maximum allowable slopes of 1.5:1 (horizontal to vertical). Short -term excavation construction and maintenance are the responsibility of the contractor and should be a consideration of his methods of operation and the actual soil conditions encountered. 5 LOR GEOTECHNICAL GROUP,.INC. AEI -CASC Engineering October 11, 2005 Shoring Desiqn Criteria Project No. 62047.13 ' Due to the heavy load transmitted by the spread foundations of the bridge and closeness of the proposed drain excavations to the bridge foundations, options such as a soldier pile wall, intrusion grouting, or other methods should be considered for support of the excavations adjacent to the bridge. The soldier pile shoring system could consist of HP piles and wooden lagging. Because of the presence of the bridge structure above the alignment, the HP piles may need to be driven in short sections and then welded to achieve the required penetration depth. Soldier pile walls unrestrained against free movement at the top should be designed to resist an active lateral earth pressure. For this condition, we recommend using an equivalent fluid density of 35 pounds per cubic foot (pcf). Passive pressures below the base of the excavation should be calculated using an equivalent fluid density of 350 pcf. The passive pressure should be ignored for a distance of 1.5 times the effective width of the pile below the depth of the excavation. A minimum factor of safety of 1.5 should be applied to the passive pressure or the pile embedment depth should be increased by 20 to 40 percent for temporary works. To aid in estimating the surcharge load transmitted by the bridge footings on the soldier pile shoring, a geotechnical sketch presented as Enclosure D -1, within Appendix D, is provided. g.. The soldier piles should be embedded below the bottom of the excavation a sufficient distance to prevent lateral movement of the piles. As encountered in our recent Boring B -4 placed within median of Cherry Avenue, - between the two existing bridges at Cherry Avenue, this location is underlain by granular soils of well graded sands and silty sands with 5 to 25 percent of gravels and no cobbles. However, south of B -4, within the location of our Boring B -3 and within all of the borings performed for the old project alignment, cobbles were found within the alluvium at depths. Thus, pile driving may encounter some difficulty due �- to the underlying cobbles. If that condition is experienced, a hardened steel point at N® the tip of the pile is recommended to facilitate the pile installation and to protect the end of the pile. The selected pile section should be able to resist not only the bending moments of the system but also to withstand the driving stresses. A LOR GEOTECHNICAL GROUP, INC. AEI -CASC Engineering Project No. 62047.13 October 11, 2005 In the event that excessive noise and /or vibration is caused by the driving operations, the soldier piles can also be set up in pre - drilled holes. Typically, soldier pile drilled holes are backfilled with concrete below the depth of the excavation and with slurry, sand, or pea gravel to the ground level. When backfill other than concrete are used to backfill drilled soldier piles, a vibratory or jetting procedures should be applied to achieve a compaction of the backfill similar to the surrounding natural soil. An alternative to the soldier pile shoring could be the application of intrusion grouting into the soil between the bridge footing and the storm drain alignment. This technique involves the intrusion under pressure of very flowable particulate grouts into the soil voids. By filing the voids, an increased soil density and improved shear strength properties can be reached. Based on our preliminary calculations, it appears that the injection of grouting within a wedge of soil extending, in width, from the face of the bridge bent footing to the face of the proposed drain box; in depth, from a line defined by the top of the bridge footing to the toe of the excavation for the box placement continuing 10 feet below the bottom of the box; and, in length, along the footing length extending 10 feet beyond in both directions, should be applied as a minimum. A required unconfined compressive strength of the grouted soil of at least 500 pounds per square inch was estimated by our calculations in order to reach satisfactory stability of the temporary excavations. Preparation of the RCB Areas M Upon excavation of the proposed RCB areas to the planned line and grade, observations and in -place density testing should be conducted to ensure that no loose materials are present. Where feasible, the bottom of the excavation should be scarified to a depth of at least 6 inches. The scarified soil should be brought to near -- optimum moisture content and recompacted to a minimum of 90 percent of the maximum dry density as determined by ASTM D 1557. After construction of the cast -in -place RCB drain, backfill materials should then be placed around the box in accordance with the recommendations given in the �.. Engineered Compacted Fill section of this report. 7 �" LOR GEOTECHNICAL GROUP, INC. ' AEI -CASC Engineering October 11, 2005 RCB Desiqn Project No. 62047.13 Provided that the RCB areas are prepared as recommended, the proposed cast -in- place concrete box may be designed using a maximum soil bearing pressure of 3,000 pounds per square foot. The vertical walls of the RCB, retaining compacted native soil backfill, should be designed to resist a lateral earth pressure between active and at -rest conditions. For this condition, we recommend an equivalent fluid density of 45 pcf be used. Surcharge load on the RCB drain due to the existing Cherry Avenue bridge foundations can be estimated using the Geotechnical Sketch, Enclosure D -1, Appendix D. Engineered Compacted Fill The majority of the soils along the project alignment are clean, free - draining, granular soils (well graded sands with gravel) with lesser units of slightly finer to finer grained, less draining materials (silty sands and sandy silts). The site soils are generally suitable for use as trench backfills and fills. However, all rocks or similar irreducible materials with a maximum dimension greater than 6 inches should not be buried or placed in fills without prior approval by the geotechnical a engineer. In addition, prior to the mechanical compaction of the fills, the materials will need to be moisture conditioned in order to achieve the desired optimum moisture content. The site soils are also considered adequate for jetted backfill due to their relatively good drainage characteristics (well graded sands with gravel and silty sands). Suitable backfill materials to be jetted should have a sand equivalent of 15 or greater. In addition, the materials of the trench walls should have a minimum sand equivalent of 15. Import fill, if required, should be inorganic, non - expansive, granular soils free from rocks or lumps greater than 6 inches in maximum dimension. Sources for import fill should be approved by the geotechnical engineer prior to their use. LOR GEOTECHNICAL GROUP, INC. AEI -CASC Engineering Project No. 62047.13 October 11, 2005 Backfill and fill materials should be free from organic material, trash, debris, and other objectionable materials. Backfill should be mechanically compacted to at least 90 percent relative compaction (ASTM D 1557) to at or near optimum moisture content. The upper 12 inches of subgrade materials that are to be paved should be compacted to at least 95 percent relative compaction (ASTM D 1557). Preliminary Pavement Design Design for preliminary pavements was conducted in accordance with the California Highway Design Manual. Based upon our preliminary sampling and testing conducted during our previous investigation, and upon Traffic Indices provided by the City of r� Fontana, it appears that the structural sections tabulated below should provide -° satisfactory pavements for the subject improvement: AREA T-1. DESIGN PRELIMINARY SECTION R -VALUE East Frontage Road 0.50' AC /0.65' AB or Cherry Avenue 10.0 50 0.80' AC /Compacted Native Access Road From Cherry Avenue to 5.0 50 0.35' AC /Compacted Native San Sevaine Basin No. 5 AC - Asphalt Concrete AB - Class 2 Aggregate Base h- The above structural sections are predicated upon 90 percent relative compaction (ASTM D 1557) of all utility trench backfills and 95 percent relative compaction (ASTM D 1557) of the upper 12 inches of street subgrade soils and of any aggregate y base utilized. In addition, the aggregate base should meet Caltrans specifications for Class 2 Aggregate Base. The above pavement design was based upon the results of preliminary sampling and testing, and should be verified by additional sampling and testing when the actual subgrade soils are exposed. =1 9 LOR GEOTECHNICAL GROUP, INC. AEI -CASC Engineering October 11, 2005 Sulfate Protection Project No. 62047.13 The results of the sulfate tests conducted on selected subgrade soils are presented in Appendix C. Based on the test results the sulfate exposures of on -site soils is considered negligible by the California Building Code. Therefore, no specific recommendations are given for concrete elements to be in contact with the site soils. �- Additional design parameters are given in the previous Subsurface Soils Investigation by this firm, Project No. 62047.1, dated May 5, 2005. LIMITATIONS . This report contains geotechnical conclusions and recommendations developed solely for -use by AEI -CASC Engineering and their designates, for the purposes described earlier.. It may not contain sufficient information for other uses or the purposes of other parties. The contents should not be extrapolated to other areas or used for w other facilities without consulting LOR Geotechnical Group, Inc. The recommendations are based on interpretations of the subsurface conditions concluded from information gained from subsurface explorations. The interpretations may differ from actual subsurface conditions, which can vary horizontally and vertically across the site. If conditions are encountered during the construction of the project, which differ significantly from those presented in this report, this firm should be notified immediately so we may assess the impact to the recommendations provided. Due to possible subsurface variations, all aspects of field construction addressed in this report should be observed and tested by the project geotechnical M consultant. The report was prepared using generally accepted geotechnical engineering practices under the direction of a state licensed geotechnical engineer. No warranty, expressed or implied, is made as to conclusions and professional advice included in this report. Any persons using this report for bidding or construction purposes should perform such independent investigations as deemed necessary to satisfy themselves as to the .g surface and subsurface conditions to be encountered and the procedures to be used in the performance of work on this project. 10 LOR GEOTECHNICAL GROUP, INC. AEI -CASC Engineering October 11, 2005 TIME LIMITATIONS Project No. 62047.13 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 Standards -of- Practice and /or Governmental 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 significant amount of time without a review by LOR Geotechnical Group, Inc. verifying the suitability of the conclusions and recommendations. ° CLOSURE It has been a pleasure to assist you with this project. We look forward to being of �. further assistance to you as construction begins. Should conditions be encountered during construction that appear to be different than indicated by this report, please contact this office immediately in order that we might evaluate their effect. Should you have any questions regarding this report, please do not hesitate to contact this office at your convenience. Respectfully submitted QROFESS /p�, LOR Geotechnical Group, Inc. CER � y Q��. R' cU Q z No. C66619 N m Gaby M. Cerva 66619 EXP Staff Engineers crvl� OF CP,,NV e ident er, GE 2030 QjkoFESS /o P• UG� �Fyc yQ�O�N 9 JJJ:GMC:JPL /mmm c� Q NO. 2030 EXPIRATION DATE z rn M Distribution: Addressee (6) 09/30/Q� OF CA�� 11 LOR GEOTECHNICAL GROUP, INC. 9 APPENDIX A Index Map and Plat e� LOR GEOTECHNICAL GROUP, INC. U u Oc BM 2 Borrow Pit Z4 lank 11 27 Gas nig 51 law W 0 0 0 \A ell J431 HIS, ILANO L 7 INDEX MAP NO.: 62047.13 PROJECT: SUMMIT AVENUE STORM DRAIN, SAN BERNARDINO COUNTY, CA PROJECT CLIENT: AE1-CASC ENGINEERING ENCLOSURE: A-1 2005 DATE: OCTOBER LOR Geotechnical Group, Inc. " SCALE: 1 = 2,000 U u SUMMIT AVENUE STORM DRAIN a PRELIMINARY ALIGNMENT S7UDY -A ALTERNATNE "D m APR CgWJW-= vx' "A BL"Ar SWFk,C"'- Ad*2t*-I" W. t � - . — _ � l .�t� :. s �-�� `'1%':... -.— -.+., ..LYE -_ ... 4 �� i -. L: 6A ��Lt7 `id!t5 5�'AD j�.!.�. AS2c- :7i --- v.?r " "? OWNER AREA fk'! s Legend * - INDICATED EXPLORATORY BORING LOCATION I EXHIBIT "E AE14�AS( CNI 0 Z L) IAJ ) O cc CL U) 0 -j L) z Lu Lu 0 0 W fy (i z >: Il-- Z FE LU Lu Z m 0 0 5 z Lu "a, CJ U) Q Z U W < cc UJI co vx' "A BL"Ar SWFk,C"'- Ad*2t*-I" W. t � - . — _ � l .�t� :. s �-�� `'1%':... -.— -.+., ..LYE -_ ... 4 �� i -. L: 6A ��Lt7 `id!t5 5�'AD j�.!.�. AS2c- :7i --- v.?r " "? OWNER AREA fk'! s Legend * - INDICATED EXPLORATORY BORING LOCATION I EXHIBIT "E AE14�AS( CNI 0 Z L) IAJ ) O cc CL U) 0 -j L) z Lu Lu 0 0 W LU -j < L) U) (i z >: Il-- Z FE LU Lu Z m 0 0 5 z Lu 0 Z CJ U) Q Z U W < cc UJI co Z 4 U) a Z cc 0 Il-- cn uj z uj > L Q CL U) M Z C 0 cr 0- �2 -i L) APPENDIX B FIELD INVESTIGATION Subsurface Exploration The site was investigated on August 31, 2005 and consisted of drilling four exploratory borings ranging from depths of 20.5 to 31.5 ± feet below the existing ground surface. The approximate locations of the borings are shown on Enclosure A -2, within Appendix A. a The drilling exploration was conducted using a CME -55 drill rig equipped with an 8- inch diameter hollow stem auger. The soils were continuously logged by a staff geologist from this firm who inspected the site, maintained detailed logs of the irr borings, obtained undisturbed, as well as disturbed, soil samples for evaluation and testing, and classified the soils by visual examination in accordance with the Unified Soil Classification System. Relatively undisturbed samples of the subsoils were obtained at a maximum interval of 5 feet. The samples were recovered by using a California split barrel sampler of �► 2.50 inch inside diameter and 3.25 inch outside diameter. The samplers were driven by a 140 pound automatic trip hammer dropped from a height of 30 inches. The number of hammer blows required to drive the sampler into the ground the final 12 inches were recorded and further converted to an equivalent SPT N- value. Factors such as efficiency of the automatic trip hammer used during this investigation (80 percent), inner diameter of the hollow stem auger (3.75 inches), and rod length at the test depth were considered for further computing of equivalent SPT N- values corrected for field procedures (zNso) which are included in the boring logs, Enclosures B -1 through B -4. The soil samples were retained in brass sample rings of 2.41 inches in diameter and 1.00 inch in height, and placed in sealed plastic containers. Disturbed soil samples were obtained at selected levels within the borings and placed in sealed containers for transport to the laboratory. All samples obtained were taken to our laboratory for storage and testing. Detailed logs of the borings are presented on the enclosed Boring Logs, Enclosures B -1 through B -4. A Sampling Key is presented on Enclosure B. r] h` a 'r 4 f CONSISTENCY OF SOILS SANDS SPT BLOWS CONSISTENCY 0-4 Very loose 4-10 Loose 10-30 Medium dense 30-50 Dense Over 50 Very dense COHESIVE SOILS SPT BLOWS CONSISTENCY 0-2 Very soft 2-4 Soft 4-8 Medium 8-15 Stiff 15-30 Very stiff 30-60 Hard Over 60 Very Hard MAJOR DIVISIONS LOGY cs. TYPICAL DESCRIPT IONS BOULDERS COBBLES SPLIT SPOON SOIL SAMPLE - INDICATES SAND CONE OR NUCLEAR DENSITY TEST INDICATES BAG SAMPLE +'. _= WELL- GRADED GRAVELS, COARSE GRAVEL FINE GW GRAVEL -SAND MIXTURES, AND CLEAN GRAVELS -f LITTLE OR NO FINES GRAVELLY (LITTLE OR NO �*� POORLY- GRADED GRAVELS. SOILS FINES) COARSE .Z' GP GRAVEL -SAND MIXTURES, GRAINED 4r� LITTLE OR NO FINES SOILS i SILTY GRAVELS, GRAVEL -SAND- MORE THAN 50% OF GM SILT MIXTURES COARSE FRACTION GRAVELS WITH RETAINED ON FINES NO. 4 SIEVE (APPRECIABLE AMOUNT OF FINES) CLAYEY GRAVELS, GRAVEL - GC SAND -CLAY MIXTURES WELL- GRADED SANDS, SW GRAVELLY SANDS, LITTLE OR SAND CLEAN SANG NO FINES AND (LITTLE OR NO SANDY FINES) MORE THAN sow, SOILS POORLY- GRADED SANDS, OF MATERIAL IS SP GRAVELLY SANDS, LITTLE OR LARGER THAN NO FINES 200 SIEVE SIZE SM SILTY SAND. SAND -SILT MORE THAN SO% OF MIXTURES COARSE FRACTION SANDS WITH FINES PASSING NO 4 (APPRECIABLE SIEVE AMOUNT OF FINES) CLAYEY SANDS, SAND -CLAY j SC MIXTURES INORGANIC SILTS AND VERY FINE SANDS, ROCK FLOUR, SILTY OR ML CLAYEY FINE SANDS OR CLAYEY SILTS WITH SLIGHT PLASTICITY INORGANIC CLAYS OF LOW TO SILTS FINE LIOUID IMIT AND MEDIUM PLASTICITY. GRAVELLY GRAINED CLAYS LESS THAN 50 CLAYS CL SANDY CLAYS. SILTY CLAYS. SOILS LEAN CLAYS ORGANIC SILTS AND ORGANIC OL SILTY CLAYS OF LOW PLASTICITY INORGANIC SILTS. MICACEOUS M H OR DIATOMACEOUS FINE SAND OR SILTY SOILS MORE THAN L IS Of MATERIAL IS SILTS LIOUID LIMIT INORGANIC CLAYS OF RICH SMALLER THAN AND GREATER THAN 50 CH PLASTICITY. FAT CLAYS NO 200 SIEVE CLAYS SIZE CLAYS OF MEDIUM =OHIG PLASTICITY, ORGANIC SAMPLING KEY Symbol Description ' INDICATES CALIFORNIA BOULDERS COBBLES SPLIT SPOON SOIL SAMPLE - INDICATES SAND CONE OR NUCLEAR DENSITY TEST INDICATES BAG SAMPLE INDICATES STANDARD _= PENETRATION TEST ISPT) SOIL COARSE SAMPLE PEAT. HUMUS. SWAMP SOILS HIGHLY ORGANIC SOILS PT I AND MANURE WITH HIGH I z. ORGANIC MATERIALS NOTE: DUAL SYMBOLS ARE USED TO INDICATE BORDERLINE SOIL CLASSIFICATIONS. PARTICLE SIZE LIMITS 12" 3" 3 14 " No.4 No 10 No. 40 200 (U.S. STANDARD SIEVE SIZE) SAMPLE KEY PROJECT: SUMMIT AVENUE STORM DRAIN, SAN BERNARDINO COUNTY, CA PROJECT NO.: 62047.13 LIENT: AEI -CASC ENGINEERING ENCLOSURE: B OR Geotechnical Group Inc. DATE: OCTOBER 2005 SCALE: NO SCALE GRAVEL SAND BOULDERS COBBLES SILT OR CLAY I COARSE7 FINE COARSE MEDIUM FINE 12" 3" 3 14 " No.4 No 10 No. 40 200 (U.S. STANDARD SIEVE SIZE) SAMPLE KEY PROJECT: SUMMIT AVENUE STORM DRAIN, SAN BERNARDINO COUNTY, CA PROJECT NO.: 62047.13 LIENT: AEI -CASC ENGINEERING ENCLOSURE: B OR Geotechnical Group Inc. DATE: OCTOBER 2005 SCALE: NO SCALE a a i c e 't L i C 1 i i i 1 PROJECT: Summit Avenue Storm Drain, Alternative D PROJECT NUMBER: 62047.11 CLIENT: AEI -CASC Engineering Group, Inc. LOR GEOTECHNICAL GROUP INC. DATE DRILLED: August 31, 2005 EQUIPMENT: CME 55 HOLE DIA.: 8" 1 ENCLOSURE: B-1 SM ALLUVIUM SILTY SAND, approximately 5% gravel to 1/2 ", 20% coarse grained sand, 30% medium grained sand, 25% fin grained sand, 20% silty fines, brown, dry. 16 5.6 122.1 ' @ 0.5 feet becomes damp. l3 7.0 118.9 , f�_ ®__w IS 25-5" 2.7 128.2 ' - = SW @ 15 feet WELL GRADED SAND with gravel, trace cobbles, approximately 15% gravel to 2 ", 25% coarse grained sand, 30% medium grained sand, 25% fine grained sand, 5% silty - = fines, brown, damp. 20 28 -2" @ 20 feet no recovery. END OF BORING No fill No groundwater No bedrock PROJECT: Summit Avenue Storm Drain, Alternative D PROJECT NUMBER: 62047.11 CLIENT: AEI -CASC Engineering Group, Inc. LOR GEOTECHNICAL GROUP INC DATE DRILLED: August 31, 2005 EQUIPMENT: CME 55 HOLE DIA.: 8" 1 ENCLOSURE: B-2 LOG OF BORING B -2 v 7 a Uj z Q O [u o m V O z .�] vi 0 O 2 1 SM ALLUVIUM SILTY SAND, approximately 5% gravel to 1/2 ", 20% coarse grained sand, 30% medium grained sand, 25% fin grained sand, 20% silty fines, brown, dry. 16 5.6 122.1 ' @ 0.5 feet becomes damp. l3 7.0 118.9 , f�_ ®__w IS 25-5" 2.7 128.2 ' - = SW @ 15 feet WELL GRADED SAND with gravel, trace cobbles, approximately 15% gravel to 2 ", 25% coarse grained sand, 30% medium grained sand, 25% fine grained sand, 5% silty - = fines, brown, damp. 20 28 -2" @ 20 feet no recovery. END OF BORING No fill No groundwater No bedrock PROJECT: Summit Avenue Storm Drain, Alternative D PROJECT NUMBER: 62047.11 CLIENT: AEI -CASC Engineering Group, Inc. LOR GEOTECHNICAL GROUP INC DATE DRILLED: August 31, 2005 EQUIPMENT: CME 55 HOLE DIA.: 8" 1 ENCLOSURE: B-2 1p 00 A" r I i PROJECT: Summit Avenue Storm Drain, Alternative D PROJECT NUMBER: 62047.11 CLIENT: AEI -CASC Engineering Group, Inc. LOR GEOTECHNICAL GROUP INC. DATE DRILLED: August 31, 2005 EQUIPMENT: CME 55 HOLE DIA.: 8" 1 ENCLOSURE: B-3 IF] rl 3 F'A 6 MA !ill P, 1� 1 1 a 20 18 5.3 112.7 , SW @ 20 feet WELL GRADED SAND with silt, approximately 5% SM gravel to 1/2 ", 10% coarse grained sand, 25 % medium graine sand, 50% fine grained sand, 10% silty fines, brown, damp. 25 10 11.0 118.0 ' 30 24 14.7 116.9 ' NIL @ 30 feet SANDY SILT, approximately 5% coarse grained sand, 10% medium grained sand, 25 % fine grained sand, 60% silty No fill No groundwater No bedrock PROJECT: Summit Avenue Storm Drain, Alternative D PROJECT NUMBER: 62047.11 CLIENT: AEI -CASC Engineering Group, Inc. TEST DATA LOR GEOTECHNICAL GROUP INC DATE DRILLED: August 31, 2005 EQUIPMENT: � HOLE D1A.: 8" z LOG OF BORING B -4 � F `� z o C LLI z� } F- ° U LQ WU �- o -� m o o DESCRIPTION 0 -- _ SW ALLUVIUM GRADED SAND with gravel, approxim. -_ j . 25% gravel to 3 ", 20% coarse grained sand, 25% medium = grained sand, 25% fine grained sand, 5% silty fines, gray 22-6" ' _ = brown, dry. _ _ @ 2 feet no recovery. 5 43 1.9 10 , 25 -3" 2.9 15, ' SM 13 15.7 116.2 @ 15 feet SILTY SAND, approximately 5% gravel to l /2 ", l0 coarse grained sand, 15% medium grained sand, 40% fine grained sand, 30% silty fines, red brown, moist. 20 18 5.3 112.7 , SW @ 20 feet WELL GRADED SAND with silt, approximately 5% SM gravel to 1/2 ", 10% coarse grained sand, 25 % medium graine sand, 50% fine grained sand, 10% silty fines, brown, damp. 25 10 11.0 118.0 ' 30 24 14.7 116.9 ' NIL @ 30 feet SANDY SILT, approximately 5% coarse grained sand, 10% medium grained sand, 25 % fine grained sand, 60% silty No fill No groundwater No bedrock PROJECT: Summit Avenue Storm Drain, Alternative D PROJECT NUMBER: 62047.11 CLIENT: AEI -CASC Engineering Group, Inc. LOR GEOTECHNICAL GROUP INC DATE DRILLED: August 31, 2005 EQUIPMENT: CME 55 HOLE D1A.: 8" 1 ENCLOSURE: B-4 E APPENDIX C LABORATORY TESTING General Selected soil samples obtained from the borings were tested in our laboratory to evaluate their physical and engineering properties. The laboratory testing program performed in conjunction with our investigation included moisture content, dry density, laboratory compaction, direct shear, sand equivalent, and soluble sulfate. Descriptions of the laboratory tests are presented in the following paragraphs: w Moisture - Density Tests The moisture content and dry density information provides an indirect measure of soil consistency for each stratum, and can also provide a correlation between soils on this site. The dry unit weight and field moisture content were determined for selected undisturbed samples, and the results are shown on the boring logs, Enclosures B -1 through B -4, within Appendix B, for convenient correlation with the soil profile. Laboratory Compaction Selected soil samples were tested in the laboratory to determine compaction characteristics using the ASTM D 1557 -00 compaction test method. The results are presented in the following table: 9 - 11 LABORATORY COMPACTION Sample Maximum Optimum Boring Depth Soil Description Dry Density Moisture Content Number (feet) (pcf) (percent) B -1 3 -4 (SW) Well Graded Sand with 135.5 7.0 Gravel Direct Shear Tests Shear tests are performed with a direct shear machine at a constant rate -of- strain (usually 0.04 inches /minute). The machine is designed to test a sample partially extruded from a sample ring in single shear. Samples are tested at varying normal loads in order to evaluate the shear strength parameters, angle of internal friction and cohesion. Samples are tested in a relatively undisturbed (u) or remolded (r) condition and soaked, to represent the worst case condition expected in the field. The results of the direct shear tests are presented in the following table: 0 DIRECT SHEAR TEST Boring Number Sample Soil Description Angle of Apparent Boring Depth Soil Description Internal Friction Cohesion Number (feet) B -3 (degrees) (psf) B -1 (r) 3 -4 (SW) Well Graded Sand with 33 250 Gravel (SW) Well Graded Sand with 50 0 B -1 (u) 10 Gravel B -2 (u) 2 (SM) Silty Sand 35 150 B -3 (u) 25 (SW) Well Graded Sand with 36 250 Gravel Sand Equivalent The sand equivalent of selected sub grade soils were evaluated using the California Q 9 Sand Equivalent Test Method, Caltrans Number 217. The results of the sand equivalent tests are presented with the grain size distribution analyses in the following table 0 SAND EQUIVALENT Boring Number Sample Depth (ft) Soil Description Sand Equivalent (SE) B -1 2 (SW) Well Graded Sand with Gravel 76 B -2 2 (SM) Silty Sand 28 B -3 10 (SW) Well Graded Sand with Gravel 65 Soluble Sulfate Content Tests The soluble sulfate content of selected subgrade soils were evaluated. The concentration of soluble sulfates in the soils was determined by measuring the optical density of a barium sulfate precipitate. The precipitate results from a reaction of barium chloride with water extractions from the soil samples. The measured optical density is correlated with readings on precipitates of known sulfate concentrations. The test results are presented on the following table: fJ OR E, F 11,i OR it I! 7 E SOLUBLE SULFATE CONTENT TESTS Boring Number Sample Depth (feet) Soil Description Sulfate Content (off by weight) B -1 3 -4 (SW) Well Graded Sand with Gravel < 0.005 B -3 10 (SW) Well Graded Sand with Gravel < 0.005 D 6� b a P I Back of wall I or pressure c surioce Design grade 71AM Figure 5.5.5.10.2-1 Horizontal Earth Pressure on Wall Due to Uniformly Loaded Strip Parallel to Wall 5.5.5.10.2 Uniformly Loaded Strip Parallel to Wall The horizontal earth pressure distribution and result- ant applied to the backof a wal I duetoauniformly loaded strip parallel to the wall may be taken as: A — = — { 180 [ 2 it arccot —arccot ph a + b b] GEOTECHNICAL SKETCH PROJECT: SUMMIT AVENUE STORM DRAIN, SAN BERNARDINO COUNTY, CA PROJECT NO.: 62047.13 CLIENT: AEI -CASC ENGINEERING ENCLOSURE: D-1 OR Geotechnical Group, Inc. I DATE: OCTOBER 2005 SCALE: NOT TO SCALE 17 wea t^ [ L z (a +b)+ b +— (a +b) b (5.5.5.10.2 -1) ph (a +b) b P=— arctan —arctan - 90 h h (5.5.5.10.2 -2) �a +b) b) h (arcian — h arctan — _ h Z 21; arctan - arctan — I h hl r (a +b)) (a + b) 90 - arctan It 2h arctan - arctan — h h b b' �90 - arctan — - 57.30ah It (a +b) b� 2it� arctan - arctan — { h (5.5.5.10.2 - 3) where_ 6 = horizontal earth pressure on the pressure i = vertical distance from the wall backfill sur- surface at back of wal I at a distance,z. from the face to the level at which the horizontal earth wall backfill surface (KSF) pressure resultant is applied (FT) z = vertical distance from the wall backfill sur- h = height of pressure surface at back of wall (FT) face to the level at which 6 is being deter- mined (KT) p = load intensity of strip load parallel to wall (KSF) P =horizontal earth pressure resultant acting on the pressure surface at back of wall (KIPS /FT) a =width of strip load (FT) b = distance from pressure surface to near edge of strip load (FT) GEOTECHNICAL SKETCH PROJECT: SUMMIT AVENUE STORM DRAIN, SAN BERNARDINO COUNTY, CA PROJECT NO.: 62047.13 CLIENT: AEI -CASC ENGINEERING ENCLOSURE: D -2 DATE: OCTOBER 2005 LOR Geotechnical Group, Inc. SCALE: NOT TO SCALE