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HomeMy WebLinkAbout; Plaza Camino Real; Soils Report; 1975-09-17INVFSTIGATT~N FOR THE PROPOSED ,A"'. 1 ..:iy p'. .” ,,,, i. .~ ,,, _,‘,_. .,.. . _,,’ .,. ,~, .~ ,, /’ ..~ ,*. .I:, ~~I~ ,-:&T.’ 1;. ,:y TABLE OF CONTENTS LETTER OF TRANSMITTAL SCOPE OF WORK DESCRIPTION OF PROJECT FIELD INVESTIGATION PLANS AND PREVIOUS SOIL REPORTS REVIEWED LABORATORY TESTS AND EVALUATION OF SOIL PARAMETERS SITE AND SOIL CONDITIONS SUMMARY OF FINDINGS, DISCUSSION AND CONCLUSIONS RECOMMENDATIONS LIMITATIONS FIGURE 1 - SITE PLAN _- / FIGURE 2 - KEY TO LOGS FIGURES 3 THROUGH 21 - LOGS OF TEST BORINGS FIGURES 22 AND 23 - GRAIN SIZE DISTRIBUTION CURVES 1 2 3 4 4 6 13 17 27 FIGURE 24 - FILL SUITABILITY TESTS FIGURE 25 - PLASTICITY CHART FIGURE 26 - LOADED SHELL TESTS FIGURES 27, 28 AND 29 - CONSOLIDATION TEST ATTACHMENT I - R-VALUE TESTS ATTACHMENT II - SPECIFICATIONS FOR CONTROLLED FILL ATTACHMENT III - GUIDE SPECIFICATIONS,FOR SUBSURFACE DRAINS WOODWARD-CLYDE CONSULTANTS CON5”LTING ENGINEERS. GEOLOGISTS AND ENY(RONMENTAL SCIENTIST5 WESTERN REGION 3467 Kurtz Street San Diego Calilornia92110 Phone (714) 224.2911 September 17, 1975 Project No. 75-173 May Stores Shopping Centers, Inc. 611 Olive Street St. Louis, Missouri 63101 Attention: Mr. Norman Barth In accordance with the request of Mr. Lawrence ROgDway of Shuirman, Rogoway & Associates, and our authorized proposal dated July 7, 1975, we have made an investigation of the underlying soil conditions in the area of the Plaza Camino Real Expansion to be located west of the existing Plaza Camino Real Shopping Center in the City of Carlsbad, California. During our study of the site, we have identified three particular conditions that will require special consideration during the development of plans for the subject expansion. These are as follows: (1) Test borings indicated that variable subsurface soil conditions are present in the areas of the proposed Sears store and the Marron Road extension. 'These areas of development are underlain by both relatively soft potentially compressible bay-estuary deposits and relatively unyielding dense formational soils. In the case of Sears Store, the soft deposits range from 0 at the southeast corner of the store, where the underlying soils consist of hard and dense Tertiary sediments, to a thickness on the order of 100 feet in the northwest corner. Marron Road is underlain by alternating areas of relatively unyielding compacted fill and Tertiary sediments and potentially compressible bay deposits, the latter having thicknesses ranging from 10 to 80 feet. (2) Present plans indicate that in the proposed Sears store area, the existing ground surface is such that finish grades will result in i irregular and variable fill loading conditions ranging from approximately j 10 feet of excavation to 18 feet of new fill. This variable loading, ' along with the variable soil conditions, could result in significant differential building settlements if not properly considered. i (3) Along the alignment of the proposed Marron Road extension, much of that portion of the road underlain by bay deposits has been surcharged; however, there are two "notch" areas not previously filled or surcharged. It is anticipated that significant settlements will occur under planned fills in these areas. May Stores Shopping 'Project No. 75-173 September 17, 1975 Centers, Inc. The accompanying report presents our conclusions and recommendations in Page 2 regard to soil conditions at the site, as well as the results of the subsurface exploration and laboratory tests upon which the recommendation.s acre based. The engineer assigned to this project is Mr. Richard P. While of our firm. If there are any questions concerning this project in which we may be of help, please call or write at your convenience. WOODWARD-CLYDE CONSULTANTS LJL/RPW/jr (2) May Stores Shopping Centers,. Inc. (2) Shuirman, Rogoway & Associates wnnn”llD” P, vne ,nuc,,t T”UTP Project No. 75-173 SCOPE OF WORK This report describes an investigation of the underlying soil conditions at the site of the proposed Plaza Camino Real Expansion in the City of Carlsbad, California. The site is located west and adjacent to the existing shopping center which is northwest of the intersection of Marron Road and El Camino Real. Our studies are intended to provide subsurface information, including depth‘of existing fills, characteristics of Potentially expansive and compressible soils and general groundwater conditions. This data provides a basis for conclusions and recommendations regarding 'site preparation and earthworking, soil stabilization, foundation design, estimates of settlements‘to be expected and paving requirements. Specifically we are presenting the following: Buildings- For building areas we are presenting recommendations for site preparation and grading, surcharge schemes for soil stabilization, foundation design including spread footings and piles, and design recommendations for retaining~walls. Paving Around Buildings- For these areas we are including recommendations for site and subgrade preparation and pavement design for various areas including car parking, loading docks and access roads. Marron Road- For the Marron Road improvements, we are presenting site and subgrade preparation, earthworking and surcharge recommendations, and preliminary pavement designs; also discissed is the effect of . . settlement on the proposed storm drain. WOOOWARO-CLYDE CONSUITIINTS Project No. 75-173 Page 2 DESCRIPTION OF PROJECT It is our understanding that the proposed expansion will generally include a two level Sears Department Store; a two level mall shops area; car parking, access roads, and loading dock areas around the stores; and the Marron Road extension, which will extend around the southern boundary of the lagoon from the existing terminus to Jefferson Street at the extreme western edge of the project. It is further understood that plans for.the expansion are in a very early stage of development; however, we were furnished with preliminary plans, dated December 20, 1973 and prepared by krumm and Sorenson, showing the basic size and location of structures. Rough estimates of finished grade elevations and building column loads were provided by Shuirman, Rogoway & Associates. This information indicates that the site will be graded into two pad levels with the lower level being approximately 27 ft, the existing level of the adjacent Penneys Store, and the upper level will be approximately 44-1/2.ft. The higher elevation will exist adjacent to the southern boundary of the Mall Shop and Sears and extend around the western edge of Sears. Retaining walls will separate the two levels. Maximum column loads to be expected in 'the building areas will be on the order of 250 kips and it is assumed that the construction w~ill be either tilt up wall masonry or steel frame with wall panels. The proposed buildings will be surrounded with car parking, a'ccess roads, and loading dock areas. For purposes of design, traffic indexes of 3.0 for car parking areas, and 5.0 for access roads and 6.0 for truck lanes was assumed. wnnnwa~n.rI vnc PnbJcIIIT”~TP Project No. 75-173 Page 3 Marron Road will be extended from its existing paved terminus along the south side of the project and will join Jefferson Street near an existing bridge. Two "notches" in the existing roadway embankment will be filled and a 5 ft diameter RCP storm drain will be installed in the roadway having a cover over the pipe ranging from 3 to 4 ft. The design traffic index for Marron Road as received from Shuirman, Rogoway & Associates is 7.5. FIELD INVESTIGATION A field investigation was performed at the site during,the period between July 22 and August 19, 1975. The investigation included a review of previous studies, a visual reconnaissance of the site and .- the drilling of test borings to determine the subsurface soil conditions. Four 4-in. diameter rotary wash borings and nine 6-in. diameter, continuous flight, truck-mounted, power auger test borings were made at the approximate locations shown on the attached Site Plan, Fig. 1. Two-in. diameter modified California drive samples, 3-in. diameter 2-l/2 fi long pitcher samples, and disturbed bags or sack samples were obtained at representative depths in the borings. The drilling was done under the supervision of an engineering geologist of our firm who prepared field boring logs on the basis of an examination of the samples secured and the excavated material. The Logs of Test Borings presented on Figs. 2 through 21 are based on an inspection of the samples'in the laboratory, the laboratory _ test results and on the field boring logs. The vertical position of each sample secured is shown on the Logs of Test Borings. WOODWARD.CIYllF CflNSlllfllNTS Project No. 75-173 Page 4 PLANS AND PREVIOUS SOIL REPORTS REVIEWED The test borings were located in the field with the aid of the previous mentioned Krumm and Sorenson plan provided us by Shuirman,, Rogoway & Associates. Other plans reviewed include the City of Carlsbad topographic survey sheets applicable to the area, a plan entitled "Interim Grading Plans - Carlsbad" prepared by Shuirman,Rogoway and Associates, dated December 9, 1971, and a recent undated plan entitled "Plans and Profiles For Street Improvements of Marron Road" also prepared by Shuirman,Rogoway and Associates. A "Report of Foundation Investigation Proposed Shopping Center El Camino Real near Vista Freeway, Carlsbad, California for Plaza Camino Real"‘prepared by Leroy Crandall and Associates, dated August 12, 1966, as well as two compaction reports, one of existing ,- filling and one of settlement analysis (also prepared by Leroy Crandall and Associates) dated April 29, 1968 and February 3; 1972, respectively, were also reviewed. A preliminary report for Hosp Grove area south and adjacent the Marron Road prepared by Woodward-Clyde & Associates was utilized in our study of Marron Road. Compaction and settlement analysis reports concerning grading in the Marron Road area and prepared by Woodward-Gizienski & Associates, dated .December 2, 1971 and September 10, 1972, respectively, also provided additional data. LABORATORY TESTS AND EVALUATION OF SOIL PARAMETERS The soils encountered in the'test borings were visually classified _ and representative samples evaluated with the respect to strength and . . compressibility chamteristics, dry density, moisture content and swelling ll,nnntn”nn e.,Ynr n.n.,r.,*r..,rr Project No. 75-173 Page 5 characteristics. The visual classifications were substantiated by grain size analyses and the determination of plasticity characteristics on representative samples of soils. The strength of the soils were estimated by unconfined compression strength tests, a direct shear test, and by a consideration of the penetration resistance of the sampler, the geologic characteristics of the formational soils, and the water content and dry density of the samples. Compressibility characteristics were established by consolidation tests on representative samples, a consideration of the water content and plasticity characteristics of the soils, and a study of settlement data on file. Swelling characteristics were estimated by loaded swell tests on both compacted and undisturbed samples and a consideration of plasticity tests. Fill suitability tests, including a laboratory compaction test, grain size analyses, a direct shear test on a compacted sample and classification tests, were performed on a sample of near surface existing fill soil. The characteristics of anticipated subgrade soils for the various areas to be paved were determined by R- value and grain size analyses tests on representative samples. The results of tests on relatively undisturbed samples, except for the consolidation tests and the loaded swell test, are shown with the penetration resistance of the sampler at the corresponding sample location on the Logs of Test Borings. The grain size distribution curves and the fill suitability tests are found on Figs. 22, 23 and 24, respectively. A chart of the plasticity characteristics and the results of a loaded swell test on a relatively undisturbed sample are presented on . ..^^_..._ -- _... -- __.._... -~~.-. Project No. 75-173 Page 6 Figs. 25 and 26, respectively. The results of the consolidation tests are reported on Figs. 27 through 29. The R-value tests, which were performed by Testing Engineers, San Diego, are attached. SITE AND SOIL CONDITIONS General Site Location and Natural Setting The subject site is situated on reclaimed marshland in the Buena Vista lagoon area approximately 1 mile from the Pacific Ocean. The site is located relatively close to the southern boundary of the lagoon, where somewhat steep side slopes rise from the lagoon to an elevated terrace area several hundred feet above the lagoon surface. The elevation of the lagoon marshland prior to any site development _- ranged from 5 to 10 ft (MSL). Several relatively large natural ridges extended in the lagoon having side slopes inclined on approximately 2 to 1. Tributary draws separate these ridges within the low level of the lagoon which extends into the tributary mouths. Relatively thick marsh vegetation covers undeveloped portions of the lagoon. Development History According to reports on file, the shopping center site was graded in phases with the first phase grading being done to accommodate the' existing shopping center buildings. The first phase grading extended west into the area of the proposed expansion and generally consisted of the placing of fill over the marsh area and beyond the limits of the -p.roposed Sears Store some 300 ft. The fill material was derived from the cutting of the nose of a prominent ridge extending into lagoon. ,,,nnn,m,.nn ..a “nr n,x.,nn.. . . ..I.... Project No. 75-173 Page 7 Approximately 20 ft of fill was placed during this period. A second phase of grading was initiated closely following the first phase and consisted of the placing of an excess of fill, to raise the existing fill grade to various pad heights in the area of the proposed Sears Store, and extending the fill out over the native marsh area encompassing the proposed parking area west of the Sears store and north of Marron Road. Settlement monuments were installed in the fill placed in the proposed parking area but not in the Sears store .area. The Phase I grading was done during the period of July to October 1966 while the Phase II grading was done during'the period of January and February, 1968. The compaction of the fills was observed and compaction tests were taken by Leroy Crandall and Associates. Reports of grading ,.- observations and compaction testing were issued on January 12 and April 29, 1968 for Phase I and II, respectively. The area of Marron Road extension was graded during the period of May 27, and September 12, 1972, and consisted.of the placing of fill from adjacent sources in the road right-of-way along the southern edge of the lagoon. The fill was compacted and brought to the design road grade, and 10 ft of surcharge was placed over the road embankment. Two "notches" were left for drainage purposes in the embankment and surcharge at approximate Stations 35 and 46+50. ' (Reference stationing of new plans). The grading observation and compaction testing were done by Woodward-Gizienski & Associates and reported on December 2, 1972. _,.I Settlement monuments were placed at several locations along the roadway; and readings were taken over a l-1/2 year period. These monuments could not be located during our recent reconnaissance of the site. WOODWARD.CIYllF CfTNSIIITINTS Project ho. 75-173 Page 8 Existing Site Conditions At the t'ime of our recent field work, the subject site appeared to be in the same general condition as at the time of final grading inspections in 1968 and 1972. In the Sears store area several pad levels exist at site elevations ranging from approximately 26 to 27 ft over the northern third of the store, 38 ft over the southern two-thirds and at the southwestern corner of the proposed building the existing ~elevation rises to an approximate elevation of 44 ft. (The pad elevations were estimated using pacing and hand level measurements with reference to available maps and no actual surveying was done). Fill banks with approximate 2 to 1 inclinations separate the various pad ~levels. The area of the Mall shops is currently occupied by~an asphalt -._ concrete parking lot ranging in elevation from approximately 27 ft, adjacent to the existing Penneys Store,to 22 ft at,the west edge of the parking lot. Some local pavement distress was noted. The proposed parking area extends west from the Sears and Mall shop area at an approximate elevation ranging from 26 to 44 ft, for a distance of approximately 300 ft, where a bank slopes down to a lower level, which extends from elevation 22 ft to elevation 16 ft at the extreme western portion of the proposed parking lot. The surface of the fills in unpaved areas are covered by a sparse growth of native grasses and weeds, and some piles of dumped trash and rubble were scattered over the site. AnimaLburrows appeared to be numerous throughout. It was also noted that several of the fill slopes had developed erosion gullys, sbme on the order of 5 to 10 ft in depth. WOODWARD-CLYDE CONSULTANTS __......_..._ _.._... ____ __^.^_.___ _"_ _" -.-_ ll.l_.. __._I_._-. Project No. 75-173 Page 9 The fills and surcharges along Marron Road have developed erosion gullys and are generally covered by a sparse growth,of weeds and grasses. Some of the surcharge has been removed in the area of Stations 31+50 to 33+00 to accommodate the installation of a sanitary sewer, which extends east from the intersection of future Monroe Avenue and Marron Road (Station 33+20) along Marron Road and thence north across the filled area to a trunk sewer located in the center of Buena Vista Lagoon. Subsurface Soil Conditions Sears Department Store - The proposed Sears store is underlain v--..-.-,.... ~,. ~- ,. -~. ~, :.: .., ,~ ~/F by compacted fill;ranging in depth from 15 to 34 ft. The fill appears .-,,,- ,...1 - to range from clayey and silty sand to silty and sandy clay and according to reports, has been compacted to an indicated minimum relative,compaction of 90% of ASTM-D 1557-66T (modified to three layers in lieu of five). The upper layers of the fill appear to be primarily clayey sand to lean sandy clay, which has been classified as low to moderately expansive in nature having a potential swell between 3 and 6 percent under a surcharge load of 160 psf. Modified penetration values throughout the fill range from 16 to 28 percent with an average on the order of 21 ft. Water contents ranged from 21 to 26 percent, with an average 23 percent. Dry densities were on the order of 123 pcf. Underlying the fill soils over most of the building area were found bay and/or estuarine deposits consisting of soft to stiff silty and sandy clay with minor clayey silt interbedded with layers and lenses of silty to clayey sand and local layers of clean sand and gravel. wnnnwaRn.cI vnr PflNClIl TANTC Project No. 75-173 Page 10 These deposits range from 0 at the southeast corner to somewhat over 100 ft at the northwest corner. In general, two zones of the bay deposits were recognized. An upper approximate 25 ft zone composed primarily of clayey soils having water contents from 22 to 65 percent, with an average on the order of 40 percent. Dry densities ranged from 55 to 105 pcf, with an average on the order of 90 pcf. A lower layer, below approximately 25 ft,is composed primarily of sandy soils having moisture contents ranging from 21 to 32 percent, with an average of 25.percent. Dry.densities ranged from 83 to 112 pcf with an average on the order of 100 pcf. Unconfined strengths of the clayey portions of the bay deposits averaged on the order of 1,200 to 1,500 pcf in the upper layer, to 1,700 to 3,500 pcf for the lower layer. Modified penetration values averaged from 9 to 19 _- blows per foot for the upper and lower layers, respectively. Underlying the southeast corner of the store, and the bay deposits at depth, is found very dense and hard silty clay and silty to clayey sand similar to materials found in local formational sedimentary deposits of Tertiary age. Geologically the materials would be considered poorly to moderately indurated claystone and sandstone. Mall Shops - Test borings made in the area of the mall shops indicate that this area is underlain by 0 to approximately 20 ft of compacted fill similar to tha; found in the Sears store area. The fill is underlain by hard silty clay and very dense clayey sand of the Tertiary sediments. Penetration values in the compacted fill were similar to _,.- those encountered in the area of the Sears store. In Boring 10, approximately WOODWARD-CLYDE CONSULTANTS Project No. 75-173 Page 11 20 ft of compacted fill was encountered underlain by relatively clean medium dense alluvial sands, to a depth of approximately 30 ft,where Tertiary sediments were encountered. According to cross sections drawn through this area and based on available maps, this should have been an area of approximately 15 ft of cut. Based primarily on the presence of alluvial soils, it is our opinion that this area was probably a narrow local drainage gully,not expressed in topographic maps,which was also subsequently filled. No potentially compressible bay deposits were ,encountered in the shops area; however, it is possible that they may infringe slightly into the area on the northwest and northeast corners. Parking Lot Areas - The proposed parking areas surrounding the Sears and mall shops are underlain by Tertiary sediments, in the southeast .- portions of the site, and compacted fill, bay deposits then Tertiary sediments over the western and northern portions of the site. The Tartiary sediments appear to be similar to those previously described. The compacted fill ranges in thickness from 11 to 35 ft, and is composed of materials similar to those previously described. Visual observations, previous reports and laboratory tests indicate that the soils at or near finish grade range from silty clay to clayey sand having R-value strengths ranging from 5 to 25. Marron Road - The proposed Marron Road extension is currently covered by a surcharge fill, which is underlain by compacted fill, bay deposits and Tertiary sediments at depth. The thicknesses and distribution . . . of various materials are somewhat variable along the alignment. From WOODWARD-CLYDE XONSIJLTANTS Project No. 75-173 Page 12 the beginning of the section, approximate Station 19+00 to Station 31+50 the alignment is underlain by 0 to approximately 5 ft of compacted fill which is underlain by Tertiary sediments. From Station approximate 31+50 to 36+00 the alignment crosses a tributary draw extending to the south. With the exception of a relatively narrow notch, at Station 35+00, the soils here consist of 10 ft of surcharge underlain by approximately 15 ft of compacted fill underlain inturn by bay deposits with a maximum thickness on the orderof 80 ft. The bay deposits are underlain at depth by Tertiary sediments. From approximate Station 36+00 to Station 38+00 the alignment is underlain by approximately 10 ft of surcharge and 0 to 5 ft of compacted fill, which is underlain inturn by Tertiary sediments. From approximate Station 38+00 to Station 41+00, 10 ft of surcharge is underlain by 0 to 10 ft of compacted fill, 10 to 40 ft of bay deposists and then Tertiary sediments. From Stations 41+00 to 44+00, conditions similar to those encountered between Station's 36+00 and 38+00 are present. In the final section from Station 44+00 to the end of the alignment, the roadway enters into the.deeper parts of the lagoon, and except for a drainage "notch" at Station 46+50, the soils encountered are approximately 10 ft of surcharge, underlain by approximately 10 ft of compacted fill, up to 100 ft of bay deposits and then Tertiary sediments. Records indicate that the su,rcharge was placed in work-like manner; however, no compaction tests were taken to indicate the degree . . of compaction. The compacted fill beneath the surcharge was compacted to a minimum of 90% relative density, as compared to D 1557-70. The Project No. 75-173 Page 13 upper zones of the fill appeared to be generally granular in nature; however, there is no indication that special effort was made to provide special select soils at finish grade. A previous test boring indicates the bay deposits at the tributary crossing are similar,in regard tp soil classification, thickness of various layers and soil parameters,to bay deposits in other parts of the lagoon. Similarly, the Tertiary deposits are expected to consist of poorly to moderately indurated claystone and sandstone. Groundwater Test borings indicate that the groundwater level over most of the shopping center site is slightly higher than the assigned level of the lagoon. Groundwater levels in the stores were measured at 'approximate ,- / elevations ranging from 10 to 15 ft (MSL). Along Marron Road in the area of the tributary,groundwater, as indicated by previous borings, is at approximate elevation 5 ft. SUMMARY OF FINDINGS, DISCUSSION AND CONCLUSIONS . Sears Store The proposed Sears store occupies an area that is characterized by four different level pad areas at elevations of approximately 22 ft, 27 ft, 38 ft and 44 ft. The subsurface soil conditions are also variable consisting of 15 to 35 ft of compacted fill underlain by 0 to over 100 ft of potentially compressible bay deposits which are underlain at depth -by poorly to moderately indurated Tertiary sediments; the latter soils underlay the extreme southeast corner of the site at a relatively shallow depth directly beneath the fill. WOODWARD-CLYDE CONSULTANTS Project No. 75-173 Page 14 In regard to the grading of the building area, it appears that the grade changes will range from 10 ft of excavation to as much as 18 ft of fill adjacent to the western boundary of the site. The effective overall uniform building loads on the underlying compressible soils are assumed to.be the equivalent of approximately 3 to 4 ft of fill. An examination of settlement curves from the monuments placed in the adjacent proposed parking area indicates that most of the settlement has taken place under the existing fill loads. The anticipated settlements under the new loading conditions are expected to range from a few inches, to as much as 12 in. total and differential primary settlement. These types of settlements are generally not tolerable in construction of the proposed store. It is our opinion that pile foundations and/or subsoil stabilization by surcharging could be employed to minimize the estimated differential settlements. For preliminary consideration, it is anticipated that piles having lengths from 50 to 130 ft will be required. It is our opinion that piles most suitable for use in this case would include steel H-beam concrete filled pipe or a combination pipe and step taper type piles. Individual pile capacities ranging from 50 to 100 tons are anticipated. Minor surcharging for fill and floor loads will generally be required in order to minimize differential settlements. Surcharges ranging from 5 to 10 ft in height over a period of 12 months should be considered for preliminary estimates. _,i. . . In order..~to minimize differential settlements, and in order to utilize spread footing foundations, it is our opinion that stabilization WOODWARD-CLYDE CONSULTANTS P~roject No. 75-173 Page 15 of the soft subsoils by surcharging could be used. Surcharge heights ranging from 5 to 20 ft of variable geometry across the building area would be necessary and loading periods would generally range from 12 to 18 months. Residual differential settlement over periods of 5 and 20 years are estimated to be on the order of 1 to 2 in. after completion of a suitable surcharge stabilization. A preliminary evaluation of the bay deposits underlying the subject building site indicate that liquefaction of the soils could occur under large seismic shocks. This could result in additional settlement of structures on spread. footings or large lateral loads on piles. A study of this condition is beyond the scope of our present investigation, but we are available to discuss this condition if such an ,- I analysis is desired. Mall Shops The mall shops area is generally underlain by relatively competent soils consisting of compacted fill and Tertiary sediments. As indicated previously, the upper layers of these soils are generally granular in nature, but may be slightly expansive requiring either undercutting and replacement with nonexpansive soils, or reinforcing of slabs and footings. The northeast and northwest corners of the mall shops may be underlain by minor zones of bay deposits and some special consideration may be required in these areas. It is anticipated that 0 to 5 ft of newcompacted fill wills be placed in the area of the shops. Some excavation may be required along . the southern edge of the shops where a fill slope currently exists. WOODWARD-CLYDE CONSULTANTS Project No. 75-173 Page 16 No grade change is anticipated at the northeast corner; more over records indicate that this area was surcharged previously for adjacent existing structures. The northwest corner however may receive up to 5 ft of fill and a minimum surcharge may be in order to stabilize the subsoil. It is our opinion that the proposed mall shops may generally be founded on conventional spread and continuous footings founded at depths of approximately 24 in. in properly compacted suitably select ii \ fill. Parking Areas,Access Roads and Loading Dock Areas Areas to be paved are generally underlain by compacted fill primarily composed of clayey sand materials; in some areas, however, ,- patches of silty to sandy clay may be encountered at grade. Since actual grades are unknown at this time , a range of anticipated subgrade soil conditions was. identified and the corresponding strength and classification characteristics established. The results of laboratory tests performed for this investigation and our experience in the areas around the subject project, indicate that materials similar to those of the subject site have R-values ranging from 5 to 25. In loading dock areas where relatively heavy trucks may be parked for extended length of time, PCC pavements may be more suitable than flexible asphalt concrete pavements. Marron Road To reiterate, the soil conditions along-the Marron Road alignment _ . . . rgnge from surcharge fill areas overlying bay deposits with relatively competent Tertiary sediments at depth, to compacted fill overlying WOODWARD-CLYDE CONSULTANTS Project No. 75-173 Page 17 Tertiary sediments; these latter conditions constitute relatively unyielding areas. A review of previous reports issued on the performance of the surcharge indicate that most of the design settlement under the permanent fill loads placed along the alignment has taken place. Additional settlement will take place upon addition of the fill load in the unload "notch" areas. Settlements on the order of 8 to 10 in. (total and differential) are estimated. The proposed storm drain will, to our understanding, be placed along the proposed road alignment and will be constructed of reinforced concrete pipe. It is anticipated that the pipe will settle with the fill in the previously indica‘ted "notch" areas. ,- RECOMMENDATIONS Building Areas - Site Grading (1) It is recommended that the site be cleared of vegetation and piles of trash and rubble. Soil and rubble may be incorpo;ated into fills below a depth of 2 ft outside building and-utility areas providing the rubble,is broken down into pieces no larger than 24 in. in maximum dimension. All vegetation and perishable material should be disposed of offsite. (2) Prior to placing any new fills or foundations, it is recommended that the upper 12 in. of rough grade be scarified, watered or dried as required, and compacted to a minimum relative compaction of 90 - ,percent as compared to laboratory compaction ASTM D-1557-70. All loose piles of soil fill should be excavated, properly prepared, replaced and .- compacted in accordance with the specifications. WOODWARD-CLYDE CONSULTANTS Project No. 75-173 Page 18 (3) It is recommended that any highly expansive soils existing in building areas be excavated from the upper 3 ft of rough grade and replaced with properly compacted suitably select soils. Suitably select soils are defined as those having a potential swell of less than 6 percent under a surcharge load of 160 psf under saturated conditions, at least 40 percent passing a No. 4 sieve size and a maximum size of 6 in. Similarily, the upper 3 ft of any design fills placed in, the building areas should be composed of properly compacted suitably select soil. Highly expansive clay soils, that is, those swelling more than 6 percent, may be placed and properly compacted in deeper portions of the fills. The building area is defined as the outline of the structure plus a minimum distance of 5 ft outside the structure limits. Areas requiring undercutting will be determined in the field by the soil engineer at the time of grading. It will beg necessary to excavate shallow pits at rough pad grade during the initial stages of grading in order to determine actual limits of highly expansive clay soils. . (4) It is,recommended that all loose ma~terial be removed from erosion gullies in any fill slopes that are to remain and the area properly prepared and filled with properly compacted soil as a part of the grading operation. (5) It is recommended that all earthworking on the site be done in accordance with the attached "Specifications for Controlled Fill". Grading at the site should be observed and compacted fills tested by Woodward-Clyde Consultants. WOODWARD.CLYDE CONSULTANTS Project No. 75-173 Building Areas - Surcharge Design ; : Page 19 i 1 (1) For preliminary designs, it is recommended that the heights and general limits of surcharges illustrated in the sketch below be considered. P 10’ !cir. ~~~~2~~ ----A ---~--jpl;-h-=~ -I;;' 0' rnj;:. Jr J+;yjj$p"' I mi;:. P- I..~.’ :,: * , -z-q- $~<‘Eqx;~.~ .;Li lkEY &d-2 E;,,50+ . . ,._I :::.,., .’ .‘.I ~1 iL: Kl :-, SKFTCH-NO SCALE This surcharge design is based on certain preliminary assumptions in regard to existing and proposed grade and building loads. Final surcharge configuration should be determined when this data is more firmly established. (2) It is recommended that the surcharge fills be compacted 'to a minimum 85 percent relative compaction and that they be placed WOODWARD-CLYDE CONSULTANTS l,."..l*.l"...""l" . . . . n.l.,n~,...."".*"l"..*".*..L .cI."ll.r. Project No. 75-173 I Page 20 e.... _.~ in a workmanlike manner. Surcharge side slopes should in general be no steeper than l-1/2 to 1 (horizontal to vertical). (3) Approximately 6 to 8 settlement monuments should beg placed in the building area prior to placing any fill and the settlements recorded by a licensed surveyor on a weekly basis during grading and for the first one or two months upon completion of grading; readings may be made monthly thereafter. The location of the‘settlement monuments will be determined in the field at the time of grading. (4) It is estimated that,the surcharge period should not exceed 18 months. Settlement readings should be forwarded to Woodward- Clyde Consultants for periodic analyses so that the actual date of removal can be established from this data. .- (5) Upon removal of surcharges and excavation to finish rough grade, the surfaces exposed should be scarified to a depth of 12 in., watered as required, and compacted to a minimum 90 percent relative compaction in accordance with earthwork specifications. Foundation Design - Sears Store (1) Conventional spread or continuous footings founded in a properly compacted suitably select fill, which is underlain by stabilized subsoils or dense suitably select natural formational soils, may be designed for an allowable soil bearing pressure of 4000 psf at a minimum depth of 24 in. below compacted or rough pad grade. All footings should have a minimum width of 18 in. A one-third increase of the bearing .pressure may be used for loads that include wind forces only. No increase is allowed for seismic forces. WOOOWARD-CLYDE CONSULTANTS Project No. 75-173 Page 21 ~.- . It is estimated that long term secondary differential settlements on the order of 1 to 2 in. over a period of 5 to 20 years, should be anticipated across the building following soil stabilization. A more detailed estimate of those settlements will be made upon completion of the surcharge stabilization. (2) It is recommended that all continuous wall footings reinforced and interior slabs-on-grade be reinforced and underlain with base material in accordance with Paragraph 2, Section Foundation Design- Mall Shops. (3) The design recommendations for resisting lateral forces are presented in' Paragraph 3 under Foundation Design-Mall Shops. Foundation Design - Mall Shops Area (1) Conventional spread or continuous footings founded in properly compacted suitably select fill or dense suitably select natural formational soils may be designed for allowable soil bearing pressures of 4000 psf at a minimum depth of 24 in. below compacted or rough pad grade. All footings should have a minimum width of 18 in. Atone-third increase in the bearing pressure may be used for ,loads that include wind or seismic forces. It is estimated that total and differential settlement under anticipated building loads in this area will be 1 in. and l/2 in., respectively. (2) It is recommended that all continuous footings be reinforced with a minimum one No. 4 bar top and bottom. The interior concrete slabs-on-grade should be a minimum 4 in. in thickness and should be reinforced with 6x6, lO/lO flat welded wire mesh placed at the midpoint WOODWARD-CLYDE CONSULTANTS Project No. 75-173 Page 22 of the slab. The slab should be underlain by a minimum 4 in. of coarse sand, crushed rock or gravel. A plastic membrane should be supplied beneath the slab wherever floor coverings are sensitive to moisture. (3) In order to resist lateral forces, friction between the base of the footing and the underlying soil or passive resistance of the soil adjacent to the footing or a combination friction and passive resistance may be utilized. If friction alone is used, an allowable friction value of .4 may be applied to designs. An allowable passive fluid weight of 300 pcf may be used for passive resistance. If passive and friction is r~ used together, a reduced friction value of .25 should be employed. Building Areas - Retaining Wall Design (1) For the design of cantilevered retaining walls, it is recommended that an equivalent fluid weight of 45 pcf be used to determine lateral earth pressures. For this condition, it is assumed that suitable select on-site granular soil will be used for backfill and thezbackfill will have a level surface. For basement type walls that are partially restrained from movement at the top, it is recommended that an additional uniform horizontal pressure of 100 psf be employed. If any other conditions or surcharge loads such as footings or vehicles are anticipated, we should be advised so that additional recommendations can be provided for design. (2) For the design of retaining wall footings, the soil parameters previously established for the Mall shops and Sears store in regard to allowable bearing and lateral resistance, may be utilized. WODDW,ARD-CLYDE CONSULTANTS Project No. 75-173 Page 23 (3) It is recommended that all retaining walls be properly drained or the walls should be designed to withstand hydrostatic pressures. A typical drain installation and specification is attached for your information. Building Areas - Pavements (1) It is recommended that all areas to be paved around buildings be generally cleared of vegetation and debris and that the upper 12 in. of subgrade in areas to receive asphalt concrete pavements be scarified to a depth of 12 in., watered as required, and compacted to a minimum relative compaction of 95 percent as compared to ASTM D-1557- 70 laboratory compaction. .^ (2) In the case of loading dock areas, it is recommended that the upper 12 in. of subgrade be composed of properly compacted nonexpansive granular soils compacted to a minimum relative compaction of 95 percent. Nonexpansive soils are defined as those select materials swelling less than 3 percent under a surcharge load of 160 psf.under saturated conditions. . Where shallow cuts or fills are made or,where no grade changes are made, it may be necessary to undercut expansive soils and replace them with nonexpansive material. The areas requiring this treatment will be determined in the field at time of grading. (3) For preliminary pavement design, it is recommended that the following table be considered. . i . . WODDWARD-CLYDE CONSULTANTS Project No. 75-173 Page 24 Use Design R-value = 5 Design R-value = 20 A.C. Base A.C. Base Car parking and traffic 2 6 2 4 Access roads 2-l/2 11 2-l/2 8 Truck lanes 3 14.5 3 10.5 Loading docks 6 inches of PCC pavement placed over compacted select subgrade The above table is based on the assumption that soil conditions at subgrade could range from silty clay to clayey sand soils. If the clay soils are excavated and replaced with granular materials in the upper 12 in. of grade, the higher R-value design may be realized in final analyses. (4) It ,is recommended that the asphalt,concrete paving and base materials conform to the State of California Standard Specifications 1973 Addition. The asphalt concrete should conform to Section 39-.04 and the material should be Class II aggregate base in accordance with Section 26-1.0218. Marron Road (1) It is recommended that the existing surcharge be removed, all erosion gullies in permanent embankment side slopes be cleaned of loose material, properly prepared and filled with properly compacted soil and all slopes be backrolled to compact the surface. (2) It is recommended that in areas where new fills are to be piaced along the alignment, the surface be properly prepared and compacted WOODWARD-CLYDE CONSULTANTS ~Project r40. 75-173 Page 25 and the fills placed and compacted in accordance with the attached earthwork specifications. The grading should be observed and compacted fills tested by Woodward-Clyde Consultants. (3) In the area between the approximate Stations 36+50 to Station 47+50, the current road alignment and proposed finish grade extends up into the overlying surcharge. It is recommended that in these areas and any other similar areas, the fills be excavated to a minimum depth~of 1 ft below the old finish grade, the area prepared and the fill replaced and compacted in accordance with the specifications. (4) It is recommended that the "notches" in the area of Station 35+00 and the area at the end of the roadway alignment be cleaned of loose material, properly prepared and filled with properly compacted .- soil. These areas should be surcharged with a minimum 15 ft high fill for as long a period as possible to help minimize future settlements. The top of the surcharge should extend a minimum distance of 10 ft beyond the permanent fill toe on either side of the roadway embankment and for a minimum distance of 20 ft on either side of the notch in a direction of the road alignment. One or two settlement monuments should be placed in the surcharge at each location and read on a weekly basis for the first one or two months and monthly thereafter. The readings should be provided to Woodward-Clyde Consultants for periodic analyses An estimate of remaining settlement will be made when it is decided to remove the surcharge. . . WOODWARD-CLYDE CONSULTANTS Ov*.YLII** .“.lD”..“., *.OLOl)l.v. ““e ***,““*m.*rA, .01.*,1.1. Project No. 75-173 Page 26 (5) It is recommended that the upper 12 in. of subgrade throughout the alignment be composed of suitably select soil compacted to a minimum relative compaction of 95 percent as compared to ASTM D- 1557-70. fin order to accomplish this, it may be~necessary to excavate highly expansive clay soils to a depth of 12 in. below sugrade surface and replace them with suitably select material. The areas of subgrade requiring this treatment will be determined in the field at the time of grading. Suitably select soil-has been defined previously in Paragraph 3 under Building Areas - Site Grading. ~ __ (6) For preliminary consideration, a pavement section consisting of 3-l/2 in. of asphalt concrete placed over 14-l/2 in. of base material is recommended. This section assumes a design R-value of 20, a traffic index of 7.5, and a general 20 year life. (7) It is recommended that the asphalt concrete and base materials conform to the specifications outlined in Paragraph 4under Building Areas - Pavements. (8) It is recommended that the proposed storm drain interceptor be located as far south in the roadway alignment as possible. It should be anticipated that some special treatment of the drain will be required in the "notch" areas noted above. This may include raising of the drain at some later .date. , i. .- wnnnwat9n.rt vnc FflMCIII TlllTP Project No. 75-173 Page 27 General Recommendations (1) It is recommended that additional studies be made as required when plans are further developed. Final recommendations for foundations for the Sears store, either piles or surcharging, can be presented in addendum reports. If a pile foundation is chosen, additional test borings will be necessary in order to estimate the pile lengths. (2) It is recommended that Woodward-Clyde Consultants review all grading and foundation plans prior to finalizing. Additional analyses and recommendations, as required, may be presented in addendum reports. (3) It is recommended that prebid and preconstruction conferences be held with the owner, architect, civil engineer, contractor or contractors and the~soil engineer in attendance. Any questions regarding special soil handling or foundations may be answered at that time. LIMITATIONS The conclusions and recommendations made in this report are based on the assumption that the soil conditions do not deviate appreciably from those disclosed by the test borings. If variations are encountered during construction, we should be notified so that we may make supplemental recommendations; if this should be required. Evaluation and utilization of soil materials and rock . . formations for support of structures includes investigation of the ~. WOOOWARO-CLYDE CONSULTANTS Project No. 75-173 Page 20 _- subsurface conditions, analysis, formulation of recommendations, and inspection during grading. The soil investigation is not completed until the soil engineer has been able to examine the soil and rock in excavations or cut slopes so that he can make the necessary modifications, if needed. We emphasize the importance of the soil engineer continuing his services through the inspection of grading, including construction of fills and foundation excavations. . . . - Location - Boring Number Elevation OTHER SAMPLE I I TfST.3 NLWBER SOIL DESCRlPTlORl ‘r I Very dense, damp, brown silty sand (SM) SOIL CLASSIFICATION - Soil Clarrificariom are baped on the Unified Sail Clarrification System and include mlor, mistwe and ccmiwmzy. Field descriprionr have been modified to reflect mwlts of laboratory analyses vAere *ppropriate. DISTURBED SAMPLE LOCATION Obtained b” collecting the auger cuttings in a plastic 0, Clofh bag. UNDISTURBED SAMPLE LOCATION MODlFlED CALfFOANlA SAMPLER Sample wiih recorded blowr per foot was obtained with a Modified California drive rambler 12” inside diameter. 2.5” outside diameter, lined v,ith ramble tubes. The rampler was driven inn, the soil at the bottom cd the hole With a 140 PO”cd hammer falling 30 inches. INDICATESSAMPLE TESTED FOR OTHER PROPERTIES GS- Grain Size Oktribution CT - Consolidation Test LC- Laboratory Compaction “CS- “nmn‘ined Compre.rion Test Tert Pi - Afterberg Limitr Test ST - Loaded Swell Test cc - Confined comprerrion T.?$f NOTE: In this column the results of there tests my be recorded where applicable. BLOW COUNT Number of blows needed to advance samqler one foot or as indicated. DRY DENSITY PO”nd, per Cubic Foot MOISTURE CONTENT Percent 0‘ Dry Weight NOTESON FIELD INVESTIGATION ‘.. 1. REFUSAL indicnta the irubility t* extend excavation. practically. With E-qqUipmnt Lwaing wed in the invertipation. KEY TO LOGS PLAZA CAMINO REAL nPaWUm". II! c I .-ucr"."P"."Jl~l Dll,-.lC,-Tsu.. 7c 171 nlTC. n ? 7c I 51"llD.z tin. c) OEPT c IN FEE 5 10 15 20 25 30 35 . . ‘H r * -- - - MC - 21 26 34 !l ro, TG - - L - ‘SC - 03 18 21 16 82 05 -_ 9 - - 07; rm - HER XS *PI - jAMP* l”MBl - I-1. l-2 l-3 4 ,- -5 : : : : : : : $ 1 , , 9 : 1 : Boring 1 SOIL DESCRIPTION Compacted, damp, brown clayey sand FILL Compacted, damp, dark gray silty clay with silty~sand zones FILL - scattered gravel and rubble Firm, saturated, very dark gray silty clay (CH) . Loose, saturated, brown silty sand with interbedded sandy clay (SM-CL) Firm, saturated, dark gray silty clay (CH) with thin interbeds of silty fine .sand --L ---__- Continued on next page *For de,cription 0‘ wnboll.‘es Figur* 2. I LOG OF TEST BORING 1 I PLAZA CAMINO REAL DRAWNBY: Al q I CHECKEOBY:~ PROJECTNO: 75-171 DATE: q-7-75 FlO”RE NO: R ,- DEPTH TES iN FEET *MC * -. 44 40 - 45 - - 36 50 : 23 55 --? I 60 -- T 0. - ‘DO - 77 -. ‘BC - 4 8 9 63 OTHEi rwrs - 3S,P - - jAMPLE IUMBEF l-6 l-7 l-8 -9 -10 I - - Boring 1, continued 1 SOIL DESCRIPTION I Firm, saturated, dark gray silty clay (CH) with thin interbeds of silty fine sand Firm, saturated, dark gray silty clay (CL) to loose, saturated, gray silty to clayey sand (SM-SC) Very dense,,saturated, gray fine to medium sand (SP) Medium dense, saturated, gray to light olive gray clayey fine sand (SC) to stiff, sandy' clay (CL) -------_ Continued~on next page *For description of wl7boll. *ee Figure 2. LOG OF TEST BORING 1 PLAZA CAMINO REAL n"AW%R"! Al c I P"F#-YF"raY. t&If mnn,EPTUn. 7r.-177 nATF. (I-3-7K I ClnllnFNnl n .- DEPTH TES IN - FEET ‘MC + : 26 I55 1 24 70 -I 75 - 80 - -a-.- 82 - . . ;T 0 - TM3 - - - BC - 2c 16 27 22 * Ic OWE TEST6 - ucs= 3500 - R : i I I SAMPL, WMBE, l-11 l-12 1-13 I -14 Borinq 1, continued SOIL DESCRIPTION I Medium dense, saturated, gray to light olive gray clayey fine sand (SC) to stiff, sandy clay (CL) Stiff to very stiff, saturated, dark gray silty clay (CH) Medium dense, saturated, gray silty medium to fine sand (SM)~ Medium dense, saturated, light olive gray clayey medium to fine sand (SC) - sand Bottom of Hole ‘For dslcription 0‘ wmbcdt. lee Figure 2. LOG OF TEST BORING 1 PLAZA CAMINO REAL DRAWN BY: ALU CHECKED BY: * $lpJl t%loJecTNO: 75-173 1 DATE: q-2-75 f=fO"RENO: 5 - DC - 03 55 - ‘BC 25 _ JTHE EST! ‘I ,c .- I-1 -2 : : : : : : : : : ; Borinq 2 SOIL DESCRIPTION 1 Compacted, damp, brown clayey sand FILL Compacted, damp, brown silty to sandy clay with clayey sand interbeds FILL - sand Compacted, saturated, brown silty sand FILL gravel Firm, saturated, dark gray silty clay (CH) with organic material brown Firm, saturated, gray to dark gray fine sandy clay (CH) to loose, silty to clayey sand.(SM-SC) -----T--P--_ Continued on next page ‘For description of rvmbolr. see Figure 2. LOG OF TEST BORING 2 PLAZA CAMINO REAL DRAWN BY: I\L.S 1 C”ECKEDeY:&9.4I PROJECTNO: 75-l 73 I DATE: o-2-75 I FIOURENO: fi _~ DEP, E IN FEE 40 45. 50 55 60 65 70 /;. . . TEST DATA - OTHE rmn 33 24 24 - 9' 0: - 2' l{ - JCS= !500 R z-4 I t-5 Borinq 2, continued SOIL DESCRIPTION Firm, saturated, gray to dark gray fine sandy clay (CH) to loose, silty to clayey sand (SM-SC) Medium dense, saturated, gray silty fine sand (SM) Stiff, saturated, dark,gray sandy clay to clayey sand (CH-SC) Medium dense, saturated, gray clayey sand (SC) -. - - ---- Continued*on next page -For dslcriptian 0‘ rymbotr. sea Figura 2 LOG OF TEST BORING 2 ~PLAZA CAMINO REAL DRAWN BY: ALS CHECKED BY: Ilxs"II PROJECTNO: 7.5-173 1 OATE q-2-75 FfO"RENO: 7 DWTH IN - FEET *MC 1 19 75 - 80 - 1 33 85 : 90 -I - 39 95 - 100 - 1 30 102 -- .,.. _ . . : A - r 0, - DO - 83 94 - - 3THE TEST! - 16 ZT,F 15 JCS= 17oc 15 GS,P - - iAMPLE IUMBEF !-7 t-8 I Boring 2, continued SOIL DESCRIPTION \ (SC) Medium dense, saturated, gray clayey sand Dense, saturated, gray silty sand (SM) I- gravel Stiff, saturated, gray silty clay with interbedded clayey sand (CH) with 'organic material Medium dense, saturated, gray clayey sand (SC) I - scattered fine well rounded gravel 1 some interbeds of sandy to clayey silt (ML) I’ interbeds of silty clay (CL) Bottom of Hole ‘For dercriprio” of wnbol~. see Figur* 2. LOG OF TEST BORING 2 PLAZA CAMINO REAL DRAWNFW: ALS LCHECKEDBY: $$q PROJECTNO: 75-173 1 DATE: g-2-75 FlG"RE Pm: 8 5 10 15 20 25 30 .- i” T a - - ‘MC 22 21 -. iT Fl - - - ‘BC 25 20 22 22 23 ‘For de~crioh” 0‘ *“Inbats. ree FiGwe 7 3-2 3-3 3-4 3-5 Boring 3 SOIL DESCRIPTION I Compacted, damp, light brown silty fine sand scattered medium gravel FILL Compacted, damp, dark gray to black silty clay FILL Compacted; moist, brown clayey fine sand FILL Compacted, moist, brown silty sand FILL d-P---__- Continued on next page LOG OF TEST BORING 3 PLAZA CAMINO REAL DRAWNBY: ALS i CHECKEDBY: $&I PROJECTNO: 75-173 1 DATE: q-7-75 F,(I”RE NO: q Borinq 3, continued TEST DATA 35 - I 37 40 - - 31 93 45 7 - 41 50 i 7 22 1 05 52 - :-T . . . 8 a 16 - KS= 1200 3-6 3-8 1 : : : : : : : : : : I ; : : SOIL DESCRIPTION Compacted, moist, brown silty sand FILL Firm, saturated, gray-brown silty clay (CH) with roots and organic matter Very ,loose, saturated, gray sand (SP) Firm, saturated, dark gray silty to sandy clay (CH) Medium dense, saturated, gray silty sand with interbedded clayey sand (SM-SC) Bottom of Hole . -For description or s”mbalr. ree Figure 2 . . LOG OF TEST BORING 3 PLAZA CAMINO REAL DHAWN BY: Al $ 1 CHECYEDW:VJ.~~~ PROJECTNO: 75-171 DATE: q-7-75 1 FIGURENO: I,, - OEP, cl- IN FEE 5 10 15 19 TEST DATA - ‘MC 12 - - ‘DO 14 - - BC 1: 2( 22 1E 5c 3THE ~E!m iS,P KS= 1500 R i I ;T ,I - 4-1 4-2 4-3 4-4 Boring 4 SOIL DiZSCRIPTION Compacted, damp, brown sandy clay FILL Compactedi damp, gray-brown silty clay FILL Dense, damp, light brown sandy to clayey silt (ML) Poorly to Moderately Indurated Siltstone Bottom of Hole *Far deKripti0” 0‘ l”mbOk. see Figure 2. LOG OF TEST BORING 4 PLAZA CAMINO REAL DRAWN By: I\LS 1 CHECKED IIY: g&i1 PROJECT NO: 75-l 73 1 DATE: g-2-75 1 FICVR~ NO: 11 Borinq 5 E L EPTH IN - FEET 5- 10 - 15 y 20 - !5 -- TEST DATA - ‘SC - T *, I 3THE rwr! SAMPU VVMBEI 5-1 [ 5-2 [ 5-3 I: 5-4 c 5-5 [ -- SOIL DESCRIPTION Compacted, damp, brown silty to clayey sand with clay zones FILL - clay - sandy clay Compacted, moist, dark gray silty clay FILL -----__--_ Continued on next page ‘For *ercriDrion of WnbOlS. see Fipurs 2. LOG OF TEST BORING 5 PLAZA CAMINO REAL . . ..L... "Y. "9 r I ^..-^.,r^ -ht,&tl ^^ ,..-,. . .,-. 7r 17- ^___ ^ e ..v -.^..- _ ..^~ . ^ OEPT II IN FEE, 30 35 40 45 50 52 _,i. . . H r * .- c - ‘MC - 27 23 34 28 42 34 29 39 - J r DI - DO - - - -1 1 F 3THEI ESTS - - SAMPLE ““MBEF 5-6[ 5-7 [ 5-8 [ 5-9 c 5-lO[ 5-1lC 5-12[ 5-13[ 5-14[ : : : : : : : : : : : : : : : : : : ! I : $ Boring 5, continued 1 SOIL DESCRIPTION 1 Compacted, moist, dark gray silty clay FILL Stiff, moist, Blacks silty clay (CH) I, Firm, wet, olive sandy clay (CL) Firm to stiff, saturated, olive silty clay (CH) Medium dense, saturated, gray clayey sand , (SC) Medium dense, saturated, brown clayey silt OIL) Stiff, saturated, gray silty clay (CH) Bottom of Hole ‘For *a,cription Of ~ymbolr. ItO Fipura 2 _ LOG OF TEST BORING 5 PLAZA CAMINO REAL -. owl c IN FEE 5 10 15 20 25 . . ‘H r - *MC - 37 41 To - ‘DO - -- - ,THE ‘ESTS - R ?.AMPU WMBEI j-1 t j-2 C j-3 C j-4 C j-5 C -- Boring 6 SOIL D.ESCRIPTION I J Compacted, damp, brown silty to clayey sand I - $ FILL dark gray sandy clay TCompacted, wet, dark gray silty clay - ** FILL Stiff to medium dense, saturated, gray clayey sand to sandy clay (CH) Firm, saturated, gray sandy clay (CH) ----____ Continued on next page ** Water level approximately 26 days after drilling. *For description Of rymbolr, ree Figure 2. t LOG OF TEST BORING 6 PLAZA CAMINO REAL DRAWNBY: ALS 1 CHECKEOBY:~~~'~~ PAOJECTNO: 75-173 I DATE: g-2-75 I FlOURE NO: 14 30 35 40 45 52 TEST DATA 28 52 37 35 30 - - SAMPLE JUMBEA 6-6 1 6-7 c 6-8 [ 6-10 c Boring 6, continued SOIL DESCRIPTION Firm, saturated, gray sandy clay (CH) Medium dense, saturated, gray clayey sand \ (SC) Firm, saturated, gray sandy to silty clay . (CH) Medium dense, saturated, gray clayey sand (SC) firm, saturated, gray silty clay (CH) with some interbeds of clayey sand (SC) r shells Bottom of Hole *For dercriptio” cd rwnbdr, see Figure LOG OF TEST BORING 6 PLAZA CAMINO REAL DRAWNBY: ,,LS 1 C"ECKEDBY:f.$%jI PROJECTNO: 75-173 1 DATE: 9-z-75 1 FlO"REHO: 15 Boring 7 GS,P :AMPLE IVMBEF 7-l t 7-2 C r-3 C ‘-4 C SOIL DESCRIPTION 1 l:: F6;rlt Concrete Hard, damp, brown silty clay (CL) 1 Poorly to Moderately Indurated Claystone I Very dense, damp, light brown clayey sand ~ (SC) Poorly to Moderately Indurated Sandstone Very dense, damp, brown clayey sand to sandy clay (SC-CL) Poorly to Moderately Indurated Sandstone and Claystone Bottom of Hole . *For descri!xion 0, tymtmk. res Figure 2 t LOG OF TEST BORING 7 PLAZA CAMINO REAL DRAWNBY: AI c I CHECKED BY: bwl PAOJECTNO: 75-177 DATE: (1-7-75 I FlD”RE NO: 16 DEPT c IN FEE 5 15 18' - 5 10 .,i. . . 14 TEST DATA - ‘MC 0 12 7 ., ii Borinq 8 OTHER SAMPLE TESTS NUMBER SOIL DESCRIPTION 51 GS,DS 8-l !il=29" c-1440 95 W - !3 - 37 - I 4" Asphalt Concrete 4" Base Very dense, damp to saturated, gray clayey sand (SC) with very thin interbeds of sandy clay (CL) 8-2 Poorly to Moderately Indurated Sandstone Bottom of Hole *For .Je,cription Of rymbolr. se* Figwe 2. I LOGS OF TEST BORINGS 8 AND 9 1 PLAZA CAMINO REAL DRAWN DY: A1.S 1 CHECKED BY: f,fl”I PROJECT NO: 75-173 1 DATE: g-2-75 1 F,C"RE NO: 17 .- - 23 26 - WPLE JMBER O-l I o-2 I o-3 I 3-4 j E Boring 10 SOIL DESCRIPTION 1 Asphalt Concrete and Base Compacted, damp, brown silty sand with clay FILL Compacted, moist, brown to gray silty clay FILL Compacted, damp to saturated, gray silty to clayey sand FILL g Medium dense, saturated, gray medium to fine sand (SP) Very dense, saturated, olive gray clayey sand (SC) Moderately Indurated Sandstone Bottom of Hole ‘For deICripti0” 0, rymbok, IBe Fiwra 2. LOG,OF TEST BORING 10 PLAZA CAMINO REAL DRAWN BY: A, $ 1 CHECKED BY: $#, PROJECT NO: 75-173 1 DATE: q-7-75 1 FlO”RE NO: ,R DEPTH 1N - FEET *MC 3-- 3 I-.- ,,.. . . roa - ‘DD - VWEF ‘ESTS - ;s,p: YI BC T c G I I s N 11 [ 1 C - iS,Pl lS,L - /\MPCE UMBER 1 1-l - 12-l J . Boring 11 SOIL DESCRIPTION Very dense, damp, light brown clayey sand (SC) Moderately Indurated Sandstone Bottom of Hole Boring 12 Compacted, damp, brown clayey sand FILL Bottom of Hole -For dn,cription 0‘ r”mbcl,. see Figure 2. LOGS OF TEST BORINGS 11 AND 12 I , PLAZA CAMINO REAL DRAwNL3Y: A1.S 1 CHECKEDBY: btvb%l PFWNECTNO: ]f,-173 1 DATE: g-2-75 f=lC"RE MO: , q Borina 13 83 18 8 13-l 13-2s 13-3 13-4 '3-5 -J SOIL DESCRIPTION Compacted, damp to moist, light brown to light gray silty fine sand FILL Soft, saturated, dark gray silty clay (CH) Medium dense, saturated, dark gray silty medium sand (SM) with slight organic odor Soft to firm, saturated, gray silty clay (CH) with silt layers Very loose, saturated, very dark gray fine sandy silt (ML) Soft to firm, saturated, dark gray silty clay (CH) Loose to medium dense, saturated, gray silty fine sand (SM) -- ----- Continued on next page LOG OF TEST BORING 13 PLAZA CAMINO REAL DRAWN fw /\LS CHECKED BY:) & ti PROJECTNO: yj-,yj 1 DATE: g-2-75 1 FlOUREWO: 20 To. - ‘DD - 12 10 - - , - ‘BC - c a 15 19 10 24 - I - DTHE ESTS KS= 2600 'I - R Boring 13, continued ;AMiYx lUMBER SOIL DESCRIPTION I Loose to medium dense, saturated, gray silty fine sand (Sk!) Medium dense to dense, saturated, gray silty 13-12 Hard, saturated, olive gray-brown fine sandy clay (CL-CH) Poorly Indurated Claystone Poorly to Moderately Indurated Claystone 'Fordercription o‘,yrnboll,*ea Figure 2. I LOG OF TEST BORING 13 PLAZA CAMINO REAL DAAWN By: ALS CHECKED BY: 1 yLi1 PAoJeCTNO: 75-173 1 DATE: g-2-75 FIOURE NO: 21 GRAVEL COBBLES I SAND C&?rse Fine SILT and CLAY cows kdium Fine I Mesh Opening - ins. Sieve Sizes I Hvdrcxneter AnLlvsis I I 1 ‘. . . 100 50 10.0 5.0 I.0 0.1 0.05 0.01 0.005 O.OOl GRAIN SIZE IN MILLIMETERS SAhiPLE CLASSIFICATION AND SYMGOL *LL 'PI l-4 Silty clay (CH) 60 39 l-6 88 64 ._ Silty clay (CH) 2-9 Siltv&ay (CL) 37 15 4 -1 Sandy clay (CL) -- -- 4-5 Sandy silt (ML) 36 10 7-1 Silty clay (CH) 56 30 *LL = Liquid Limit 'PI = Plasticity Index I GRAINSIZE DISTRIBUTION CURVES I I PLAZA CAMINO REAL DRAWNDY: ALS j CHECKEOUY:~~~~ P”OJECTNO: 75-173 1 DATE: g-4-75 PIOVRE NO: 22 GRAVEL COBBLES I SAND Coarse Fine SILT and CIAY coars Medium Fine I Mesh Opening - ins. Sieve Sizes Hvdrometer Analvsis r I I I 100 0 90 IO 60 7.0 70 30 z 0 60 1K)z Y 2 0. is 5 2 50 505 2 % 90 60 30 70 20 60 IO 90 0 loo 100 50 10.0 5.0 I .o 0.1 0.05 0.01 0.005 0.001 GRAIN SIZE IN MILLIMETERS _,:. . . ‘LL = Liquid Limit ‘PI = Plasticity index GRAIN SIZE DISTAIBUTION CURVES I PLAZA CAMINO REAL D”AWN “Y: A1.S CHECKED OY: uq PROJECT NO: 75-173 1 DATE: g-4-75 FIOURE NO: 23 PLASTICITY CHARACTERISTICS 12-1 Liquid Limit, % 31 Plasticity Index, % 13 Classification by Unified Soil Classification System SC COBBLES1 ;A;y 1 c, Fy f 1 SILT b CLAY 150 ZERO AIR VOIDSCURVES GRAIN SIZE. mm MECHANICAL ANALYSIS DIRECT SHEAR TEST DATA 12-1 I 1 b* “D”ri+l, nr‘ I, 1, n I I I , Y”‘as.,, r”, I, I, .+ I Initial Water Content. % 11.6 1 t Final Water Content, % WI! Apoarent Cohesion. orf 410 I I Apparent Friction Angle, degrees 20 I SWELL TEST DATA I--I I .I Dry Qenaitv, pcf I water content, % I t ._ -_ -- 40 LABORATORY COMPACTION LABORATORY COMPACTION TEST TEST METHOD: &m D 1 !i!i?'-7f-l I FILL SUITABILITY TESTS 1 I PLAZA CAMINO REAL DHAWN DY: A[ s CHECKED BY: vi% ~PROJECT NO: 15-173 1 DATE: g-4-75 FIGURE NO: 24 I I 7-l 0 0 IO 20 30 110 50 60 90 loo LIQUID LIMIT. LL PLASTICITY CHART. For Classification of Fine - Grained Soils in Unified System Legend CL CH ML HH OL OH SM SC Inorganic clay of la, to medium plasticity. Inorganic clay of high plasticity. Inorganic silt of lcw plasticity. Inorganic soil of high plasticity. Organic silt or clay of Icw plasticity. Organic clay of high plasticity. Silty sand. Clayey sand. , . . I PLASTICITY CHART PLAZA CAMINO REAL O"AWN~,Y: I\I,.S 1 CHECKEOBY:‘#~l PROJECTNO: 75-173 1 DATE: g-4-75 1 FIOUHENO: 25 RESULTS OF LOADED SWELL TESTS -!I iample lumber 4-l Initial Dry ensit) & 106.3 fiater >nteni Ji= 13.8 * aturatio -s- 67 Final T Dry ensit: pcf 101.4 ,Diameter of Samples: A-6"; inches Height of Samples: . 9 inches Water ontent L 23.5 * aturatio -7L 99 P n 1 T 'ressur' psf 160 Expansion % of Initial Heigh 4.8 *assumed specific gravity - 2.65 LOAOEDSWELLTESTS L PLAZA CAMINO REAL DRAWNOY: ALS 1 C"ECKEoBY:$p~ PROJECTNO: 75-173 1 o*TE: n-29-75 1 FlO"REN0: 26 . ..-^_..._^- ^. .,^_ ^ ^_._... --..w,. SAMPLE 1 - 4 1.24 1.16 1.08 0 5 E 1.00 z 4 e0 - -- PRESSURE - Tons per sq. ft. . . I CONSOLIDATION TEST PLAZA CAMINO REAL SAMPLE 2 - 2 2.2 2.0 1.8 1.6 1.4 1.2 1.0 10.0 PRESSURE - Tons per sg. ft. - - - - - - - - - 100 . . CONSOLIDATION TEST PLAZA CAMINO REAL DRAWNBY: Al < I CHECKED fw: \.; 'W, PROJECTNO: 75-171 DATE: q-a-75 I Flo"RENO: 31) SAMPLE ~2 - 7 0.72 U.b8 o 0.66 2 ~1 0.64 G 0.62 0.60 0.58, 0.56 0.01 0.1 i . . PRESSURE - Tons per sg. ft. INITIAL DRY DENSITY, pcf 95.4 SPECIFIC GRAVITY OF SOLIDS 7.67 INITIAL WATER CONTENT, % 30.0 INITIAL VOID RATIO, eo 0.75 INITIAL SATURATION, $ 100 COMPRESSION INDEX, c, 0.114 FINAL DRY DENSITY, pcf 101.8 SWELL INDEX, C, 0.031 FINAL WATER COKTENT, % 25.4 EFFECTIVE OVERBURDEN PRESS, P',,. tsf 2.56 FINAL SATURATION, $ 100 MAX. PAST PRESSURE, PC. tsf 0.79 CONSOLIDATION TEST PLAZA CAMINO REAL DRAWN BY: ALS 1 CHECKED BY: k WI PROJECTNO: 75-173 I DATE: 9-4-75 I Flo"REN0: 29 l”,nn”lr,““n n, “nr ““.,.-III IL.IIC Project No. 75-173 ATTACKlENT I Page 1 of 2 TESTING ENGINEERS - SAN DIEGO 3467 KUR’IZ ST.. P.O. BOX 80985. SAN DIEGO. CA 92138 (714) 225.9641 Lneon*TonY NilMBER, SD3&3,95 Job No. 1086 DATE August 8, 1975 JOB m&T*: Plaza Camino Real Expansion SAMPLE DATA:Job No. 75-173, S/N i: 11-l. Woodward-Clyde Consultants 3167 Kurt2 street San Diego, California 92110 Boring #ll. Sample subkited to the laboratory August 1, 1975. X GRADlNG ANALYSlS ;IE”E SUE 3” 2” %” I,(, .’ _o*’ -4 8 a6 r30 =50 ,- 100 PERCENT PASSlNG As RCVD. AS “*ED -- izxm :M*RKS: *. 1 cc. TllC : nn zz - = cOMP*cTOR PRES5 P.S.,. h4msr @ CDMPACTlON 76 - DENslrr 1 #,CU. FT. R-VALUE STABILOMETER EX”D. PftESSURE P.S.,. STAFI THICK FEET EXPAN. PRESS. TH,cx.FEET 1 T. 1. ~AssuMco, = m-v z=z R- “I\L”E DATA F 23.9 I I 99.3 1 I “I\L”E DATA c D r E 130 23.9 -- 99.3 15 570 --- 0.50 15 I I 0.50 I I BKSTAB. @ 300 P.S.!. EXUD. = 8 BY EXPANSION PRESSURE = --- AT Es!JlLleRl”M = a = SAND E.aUl”ALENT = ---- DUR*BIL,TY cCo*nsE, = 3”RABILITY (FINE, = LlQ”lD LlMlT = PLASTlC LlMlT = P. 1. = Project No. 75-173' ATTACHMENT I 'on"'n" Page 2 of 2 TESTING ENGINEERS - SAN DIEGO 3467 K”Rl-2 ST.. P.O. BOX 80985. SAN DIEGO. CA 92139 (714) 225.9641 __ LIIBORIITOHY NUMBER SD30-3736 Job No. 1086 D*TE August 8, 1975 - JO" DATA: Plaza Camino Real Expansion SAMPLE DATA: Job No. 75-173, SIN 1112-l. Woodward-Clyde Consultants 3467 Kurtz Street San Diego, California 92110 GRADING ANALYSIS 4CYE .~> IL E 2,” 3,, _, ,, i ” -4” L,!, -8 .)S I, f ‘j :~ 8 2 1 6 =30 250 ~‘100 PERCENT PASSING AS RCVD). AS UsEo _- rT(cm .i. :;%I*RK*: 1 CC. ,- Boring #12. Sample submitted to the laboratory August 1, 1975 1 cOMP*CTOR PRES5. P.S.,. MOET 0 COMPACTtON % - ., DENSITY . +,cu. FT. R.“AL”E STABlLOMETER EXVD. PREBSURE . P.S.,. ST*% THICK . FEET Em-AN. PnEss. THICK-FEET T. 1. fA55”MEDl = . - 1 1 I 150 95 120 13.8 15.6 14.7 18.1 113.3 116.3 16 9 13 380 180 260 --- --- ___ 0.53 0.03 0.27 --- --- E -__ ~- Y $; BY STAB. B 300 P.S.,. EX”D. = 15 :; BI EXPANSION PRE5SURE = ___ AT E9UILIBRI”M = 15 SAND EwJI"ALENT = -- DURABILITY ,Co*nsE, = LlQ”l.3 LLMIT = Dun*eluTv (FINE, = PLISTK LIMIT = I=. 8. = -.Y n I.I,P. r.” ;g.yjgg ‘Plmmna l, P,.nn”.n” 1, r.. 111 1001 .~ ~-. I II .- III Project No. 75-173 .- ATTACHMENT I1 'Page 1 of 4 SPECIFICATIONS FOR CONTROLLED FILL GENERAL These specifications cover preparation of existing surfaces to receive fills; the type of soil suitable for use in fills; the control of compaction and the methods of testing compacted fills. It shall be the Contractor's responsibility to place, spread, water and compact the fill in strict accordance with these specifications. A Soil Engineer shall be the Owner's representative to inspect the construction of fills. Excavation and the placing of fill shall be under the direct inspection of the Soil Engineer ; and he shall qive written notice of conformance with the specifications upon completion of grading. Deviations from these specifications will be permitted only upon written authorization . from the Soil Engineer. A soil investigation has been made for this project; any recommendations made in the report of the soil investination or subsequent reports shall become an addendum to these specifications. SCOPE The placement of.controlled fill by the Contractor shall include all clearing and grubbing, removal of existing unsatisfactory material, preparation of the areas to be filled, spreading and compaction of fill in the areas to be filled, and all other work necessary to complete the grading of the filled areas.- MATERIALS 1. Materials for compacted fill shall consist of any material imported or excavated from the cut areas that, in the opinion of the Soil Engineer, is suitable for use in constructing fills. The material shall contain no rocks or hard lumps greater than 24 inches in size and shall contain at least 40% 1 of material smaller than l/4 inch in size. ('Materials greater than 6 inches in size shall be placed by the Contractor so that ~they are surrounded by com- pacted fines; no nesting of rocks shall be permitted.) No material of a perish- able, spongy, or otherwise of an improper nature shall be used in filling. 2. Material placed within 24 inches of rough grade shall be select material that contains no rocks or hard lumps greater than 6 inches in size and that swells less than 3% when compacted as hereinafter specified for compacted fill and when subjected to an axial pressure of 160 psf. 3. Representative samples of material to be used for fill shall be tested in the laboratory by the Soil Engineer in order to determine the maximum density, optimum moisture content and classification of the soil. In addition, the Soil Engineer shall determine the approximate bearing value of a recom- pacted, saturated sample by direct shear tests or other tests applicable tom the particular soil. 4. During grading operations, soil types other than those analyzed in the report of the soil investigation may be encountered by the Contractor. The Soil Engineer shall be consulted to determine the suitability of these soils. Project No. 75-173 .4TTACHr,iENT II Page 2 of 4 IV COMPACTED FILLS 1. General ', (a) Unless otherwise specified, fill material shall be compacted by the Contractor while at a moisture content near the optimum moisture content and to a density that is not less than 90% of the maximum density deter- mined in accordance with ASTM Test No. D1557:70T, or other density methods that will obtain equivalent .results., (b) Potentially expansive soils may be used in fills below a depth of 24 inches and shall.be compacted at a moisture content greater than the optimum moisture content for the material. 2. Clearing and'Preparin9~Areas to~be.Filled (a) All trees, brush, grass, and other objectionable material shall be collected, piled and burned or otherwise disposed of by the Contractor so as to leave the areas that have been cleared with a neat and finished appearance free from unsightly debris. (b) All ~vegetable matter.and objectionable material shall be removed by the Contractor from the surface upon which the fill is to be placed and any loose and porous soils shall be removed or compacted to the depth shown on the plans unless otherwise.specified in writing by the Soil Engineer. The surface shall than be plowed or scarified to a minimum‘ depth of 6 inches until the surface is free from uneven features that s would tend to prevent uniform compaction by the equipment to be used. '(c) Where fills are constructed on hillsides or slopes, the slope of the original ground on which the'fill is to be placed shall be stepped or keyed by the Contractor as shown on the attached Figure. The steps shall. extend completely through the soil mantle and into the underlying for- mation materials. (d) After the foundation for the~fill has been cleared, plowed or scari- fied, it shall be disced or bladed by the Contractor until it is uniform and free from large clods, brought to the proper moisture content and com- pacted as specified for fill. 3. Placing, Spreading, and Compacting Fill Material (a) The fill material shall be placed by the Contractor in layers that when compacted shall not exceed 6 inches. Each layer shall be spread evenly and shall be thoroughly mixed.during the spreading to obtain uni- formity of material in each layer. . . (b) When the moisture content of the fill material is bel that speci- fied by the Soil Engineer, water shall be added by the Contractor until the moisture content is as specified. (c) When the moisture content of the fill material his above that speci- fied by the Soil Engineer, the fill material shall be aerated by the Con- tractor by blading, mixing; or other satisfactory methods until the moisture content is as specified. Project No. 75-173 ATTACHMENT II Page 3 of 4 V ,._VI (d) After each layer has been placed, mixed and spread evenly, it shall be thoroughly compacted by the Contractor to the specified density. Com- paction shall be accomplished by sheepsfoot rollers, vibratory rollers, multiple-wheel pneumatic-tired rollers or other types of acceptable corn7 patting equipment. Equipment shall be of such design that it will be able to compact the fill to the specified density. Compaction shall be con- tinuous over the entire area and the equipment shall make sufficient trips to insure that the desired density has been obtained. (e) Surface of fill .slopes shall be compacted so that the slopes are stable and there shall be no excessive loose soil on the slopes. INSPECTION 1. Observation and compaction tests shall be made by the Soil Engineer during the filling and compacting operations so that he can state his opinion that the fill was constructed in accordance with the specifications. 2. The Soil Engineer shall make field density tests fin accordance with ASTM Test No. D1556-64T. Density tests shall be made.in the compacted materials below the surface where the surface is disturbed. When these tests indicate that the density of any layer of fill or portion thereof is below the speci- fied density, the particular layer or portion shall be reworked until the specified density has been obtained. PROTECTION OF WORK 1. During construction the Contractor shall properly grade all excavated surfaces to provide positive drainage and prevent ponding of water. He shall control surface water to avoid damage to adjoining properties or to finished work on the site., The Contractor shall take remedial measures to prevent . ' erosion of freshly graded areas and until such time as permanent drainage and erosion control features have been installed. 2. After completion of grading and the Soil Engineer has finished his obser- vation of the work, no further excavation of filling shall be done except under the observation'of the Soil Engineer. _,.- . . Project No. 75-173 ATTACHXNT II I Page 1 of 2 GUIDE SPECIFICATIONS FOR SUBSURFACE DRAINS I. DESCRIPTION Subsurface drains consisting of standard drain tile, perforated Orangeburg drain pile, or perforated corrugated metal pipe, shall be installed as shown on the plans and in accordance with these specifications, unless otherwise specified by the Engineer. II. MANUFACTURE Underdrains shall be manufactured in accordance with the following requirements: 1. Standard drain, tile shall conform to the requirements of ASTMD-C4. 2. Perforated Orangeburg pipe shall conform to the Federal Specifi- cations SS-P-356. 3. Perforated corrugated metal pipe shall conform to the AASHOD-M136. III. FILTER MATERIAL Filter materiallfor use in backfilling trenches around and over under- drains shall consist of clean, coarse sand and gravel or crushed stone cbn- forming to the following grading requirements: SIEVE SIZE PERCENTAGE PASSING SIEVES 2-112" 100 i l-l/2" 80-100 314" 60- 95 No. 4 35- 65 No. 8 25- 50 No. 30 L 5- 25 No. 200 o- 3 IV. LAYING Trenches for underdrains shall be excavated to to the outside diameter of the pipe plus I!.foot and below the top of the wall footing or as directed by of the trench~shall then be covered ftill width by a a minimum width equal to a depth of 2 inches the Engineer. The bottom layer of plastic film or building paper, and the drain pipe shall be laid. Unless otherwise specified, perforated pipe shall be laid with the‘perforations at the bottom and sections ;I shall be joined with couplers. Drain tile shall be laid with a clear opening of l/2" between sections. The pipe shall be laid on's minimum slope of 0.2%. After the pipe has been placed, the trench shall be backfilled with filter material to the elevation: shown on the plans, or as directed by Engineer. The remainder of the trench shall then be backfilled with an impervious soil which shall be compacted to the requirements for engineered fills. Project No. 75-173. ATTACHMENT III Page 2 of 2 GUIDE SPECIFICATIONS FOR SUBSURFACE DRAINS (CONTINUED) s- . *,v . a.; ,‘_ ; ’ :. ., A’ ,q ‘: :. . . . ‘9. .% - * ..{’ : .:. . 9.’ ..: :-,:a s* p lUPERVlOUS SOIL r ‘- WATERPROOF MEMBRANE FILTER MATERIAL 16” Min. TYPICAL SECTION 4” DIA. PIPE PLASTIC FILM CR BUILOING PAPER