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HomeMy WebLinkAbout; Palomar Airport Business Park Lot 12; Soils Report; 1984-03-09- - - - - - ROBERT PRATER ASSOCIATES Roberr R, Protei. C.6 ,942.,980 Conrulmg Soil. Foundation d Geolopicol Engineers Wm, David Herpeier. C E, March 9, 1984 218-1E. 5661 ConwelllMarshall 6 Associates, Inc. 3160 Camino Del Rio South, Suite 217 San Diego, California 92108 Attention: Mr. Christopher Knell Re: Neil Fox Development Palomar Airport Business Park - Lot 12 Carlsbad, California Gentlemen: ENtjlNEERlNG DEPT. LIBRARY City of Carlsbad 2075 Las Palmas Drive Carfsbad CA 92009-4859 In accordance with your request we are presentlng design recommendations for retaining walls constructed on sloping ground. Our letter dated November 28, 1979, presented foundation design recommendations and the results of our earth- work observation and testing services performed during the mass grading of the site. It is our understanding the unrestrained retaining walls will have sloping 2 horizontal to 1 vertical backfills and will be up to about 10 feet high. .- Based on our previous work on the site, we recommend that unrestrained walls with 2 to 1 sloping backfills be designed for an equivalent fluid weight of 45 pounds per cubic foot (pcf). This design pressure is based on the assumption that a clean sandy soil will be used as backfill within a 1 to 1 zone behind the wall and that there is sufficient drainage behind the walls to prevent the build-up of hydrostatic pressures from surface water infiltration. Wherever the walls are subject to surcharge loads they should be designed for an additional uniform lateral pressure equal to one-third the anticipated surcharge pressure. Retaining walls which have 2 to 1 sloping ground at the toe of the wall should - be designed for an allowable passive pressure equal to an equivalent fluid weight of 150 pcf acting against the foundation. Walls founded in level ground may be designed for an allowable passive pressure equal to an equivalent fluid - weight of 300 pcf. An allowable friction coefficient of 0.35 is recommended for use in design. Backfill placed behind the walls should be compacted to a minimum degree of compaction of 90 percent using light equipment. If heavy equipment is used, the walls should be appropriately temporarily based. - - lC1935 Roreile Srreer Son Diego, Col,lornra 92121 (ON, m-m .- - - _ March 9, 1984 218-1E. 5661 Page 2 Retaining walls should be supported on footing foundatlons designed in accor- dance with the recommendations presented in our November 28, 1979 letter, except that for low walls (less than 4 feet high) founded in level ground the footing embedment depth may be reduced to 12 inches below the lowest adjacent flnished grade. Our November 28, 1979 letter indicates that the compaction of utility and storm - drain trench backfills was not completed. Accordingly, unless there is proper documentation indicating that the trenches were subsequently properly com- pacted, we recommend that uncompacted backfills be removed and properly recom- - pacted to a distance of 5 feet on either side of the retaining wall alignment. Our services consist of professional opinions‘and recommendations made in accordance with generally accepted geotechnical engineering principles and - practices. This warranty is in lieu of all other warranties either express or implied. - If you have any questions, please call. Very truly yours, - ROBERT PRATER ASSOCIATES Leslie H. Pennington, k., RCE No. 32,054 - LHP: Is Copies : Addressee (3 1 Coneer Engineering, Attn: Mr. Kurt Pfizenmaier (1) - - - Romr *RATER ASSOCIATES bmd*n~ bJ6cw.-domn b +.logu,l togmec,, - November 28, ‘1979 ZlB-lE, 3098 Polomar Airpart Business Park - 6231 Yarrow Drive, Suiteet Carlsbad, California 92OOB - Attention: Mr. Bernard W. Gllmare Re: Earthwork Observatian and Testing Services - And Foundation Re -ddiWS Carlsbod Tract No. 79-t - Parcel B of Cot 12 - Palamrr Airport Business Park Carlsbad, California -- . Gentlemen: -. In occordonce with your request we hove provided earthwark observation ond testing services in connection with’the mass grading aperotiam far the subject project. A geo- kchnical investigation far the btniness park was perfarmed by our predecessor firm the results of which were presented in orepart entitled “Gcotechnical tnvertigotian, C.C. B F. Patom- Airport Business Pmk - Phase 1, Cwlsbad, Califanio,” doted Februmy 26, 1974. .- Our representatives were present d the site on an intermittent basis from August 31, 1979 to October 12, 1979 to observe the cnors grading operations and to provide field density testing services as required. The approximate locations af OIR field density tests are shown an the attached Site .Plans, Figues 1 and 2. The results of OUT field density and loboratary campoction tests are presented in the attached Tables A and B. - Based an our observations and the attached test results, it is our opinion that the moss e&h- work operations were ccrried aut in accordance with the recamendotions of the geotechnicol investigation report ond thot 011 fill moteriol was compacted to a minimum degree of compoc- tion of 90 percent bored on ASTM Test Designotion 01557-70. Work remaining at the site which will require additional earthwork testing and inspection services includes 1) finish grading ape&ions for individual building pods which will probably require odditionol cuts and fills of probobly less thon two or three feet deep, 2) compaction -. ‘fK? r ‘;* SW.!. $00 D,cpo, CdJ,,rnloV2l?l .,,,.,‘SM&X / C,,A,,a Y,,ro 0,~ SWI, It& ,‘,,,Q ~o,,,o,n.o ~2~5, .I,,,, m-91,. _- - Nwember Lb, ii, i 218-lE, 3098 PW~ 2 of utility ad storm drain trench &&fills which hove not been ampleted 01 of this dote, 3) prepmotion and compoctian of pavement subgrode soils, and 4) ploccment ond com- poction of pavement base rock materiots. - We recommend thot propased buildings be supported on conventional, individuol spread and/or cantinuous perimeter footings bearing on firm noturol sail and/or compacted fill moteriols. footings should be founded ot least 18 inches below the lowest odjocent ~finished grade. At this recommended depth, footings may be designed far allowable &wing pressures of 2,500 pounds per square foot (psf) for dead l&dr, 3,500 psf for combined deod ond live loads, ond 4,500 psf fa oil loads, including wind or seismic. The footings should, however, have a minimum width of 12 inches. All continuous footings should be reinfarced with top ond bottom reinforcement to provide strudurol continuity ond to permit spanning of local irregulmitiu. Post-construction differential settlements across the buildings ore expected ta be within toterable limits for the structures. - _- -- Building fioar slobs may be supported directly on cornpocted fill and/or notual soil. Slob reinforcing should be provided in accordonce with the anticipated use of ond loads on the slobs. tn areas such as offices where moisture-sensitive floar coverings me to be utilised ond in other meas where floor dampness would be undesirable, we recommend thot can- siderotion be given to providing on imperrneoble membrane beneath the slabs. The mem- brane should be covered with 2 inches of sand to protect it during construction. The sond should be lightly moistened lust prior to placing the concrete. 1 Poorly graded imported son& and/a gravels (such os pea gravel) should not be used in arem where slabs will be subjected to concentrated heavy loads such as would be inpased by loaded faklifh. - Lateral load resistance for building foundations moy be developed in frictian between the bars of the founddiam and the wing +rade. An ollowoble friction co&c&? of 0.35 is recommended fa use in d&g”. &I odditianol ollowoble passive pressure quo! ta m quivolent ft3d weight of 300 pounds F cubic foot acting against the foum&;on soy be used in design Provided the foot+ ox Paured neot ogoinst undistubed soil. These ollow- oble values m bared on o safety focta of 1.5 applied to the ultimate values. Any dock high retaining walls mut be designed to resist lotcrol earth prerrues from the .- bockfill materials as well or my floor surcharge loads. It is recommended that walls re- strained from movement ot the top be designed for on quivolent fluid preuve of 30 pounds per cubic foot plus an odditionol unifam lotcrol pressure of 5H pounds per squm-c foot, where - H is the height of bockfill obave the wall footing in feet. Unrestrained wollr may be designed far the 30 pounds per cubic foot quivatent fluid pressus only. Wherever walls will be sub- ject to surcharge loads, they should be designed for on odditionol uniform lateral pressure - quo1 to one-hotf the anticipated surchorgs pressure in the case of rcstroined walls ond one- third the anticipated surcharge pressure in the cme of unrertroined walls. - - - - - - .- - - - - - - - - Bmed on our general knowledge of the soils present on tk rubiect lots and our post experience in prwiding R-voluc test resufh far similar sofls within the business Park, it is our opinion that a design R-volw of at least 30 is appropriatifar UK at this site. Combining this Rwolue with selected traffic indices fm different pavement looding re- quirements we have developed the following recommended pavement sections using Pro- cedure 301-F of tk State of Califanio, Oepmtment ofTronsp.ortation. The recommended pavement sections contained in Table 1 should provide o pavement life of 20 years with o narmol amount of flexible pavement maintenance. TABLE I - RECOMMENDED PAVEMENT SECTIONS Prrvement Conpanents Asphalt Concrete 4;ri,a; Bme Total Thickness location (Inches) (Inches) (Inches) Automobile Parking Areas 2.0 4.0 6.0 fT.1. =3.5for20-year life) Traffic Channels md areos 3.0 5.5 8.5 subject to occassianol heavy vehicular loads such os would be imposed by ,trosh trucks (1.1. = 5.0 f@ 20-yeor life) Our services consist of profeuionol opinions end recommendations mode in occardance with generally accepted soil and foundation engineering principles md proctlco. This wuronty is in lieu of oil other worronties etther express Q implied. If you have ony questions, please call. Very truly yours, ROBERT PRATER ASSOCIATES Robert Prater, C.E. RP:lmt Attochmnts Copies: Addressee (3) Peter A. Lendrum Arsociotel, Attn: Mr. Ed Wright (2) - - - - - - - - - - -~ -~ - - - - &pr&e hole (Feet) I LEGEND l 1 lndicotes approwimote location of field density test. B-e: Sheet 2 of o set of Qroding plans entitled “Corlrbod Tract No. 79-l Polomor Airport Business Park,’ by Henry Worley Atrociater, doted July 12, 1979. SITE PLAN ROSCRT PRATER MSOClAlEJ tc..u*,.p so.! La-&+- . CIohprd r~“,w, PALOMAR AIRPORT B S;fEjS PARK x - CARLSBAD TRA Corlrbod, Colifornio ?llWECT NO. MU 21B-1E 1 November 1979 LEGEND . I Indicoto oppraxllnotr Iocollorl of field dcmity test. Bose: Sheet 3 of set of rodi Business Par 1,” by !ienr$%kley lam entitled “Corlsbod froct NO. 79-l Polomor AirPort ks ociotcr, doted July 12, 1979. I / I 1 I I I I I I I I I I I I I I I TABLE A - SUMMARY OF FIELD DENSITY TEST RESULTS (ASTM 01556-64 and/or ASTM b2922-71,eASTM 03017-72) Test Approrlmote Il0votlon No. Dote of Tot Too Locatlon (Feet) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 8/31fl9 E/51/79 a/+1/19 9/04/79 9/04/19 9/04/79 9/06/19 9/05/19 9/05/79 ‘9/05/f9 9/ow9 9[05/19 9/06f79 9/06/79 9/06j79 9/06/19 9/07/19 9/07/19 9/07/79 9/07/13 Lot I 277 Lot 1 278 Lot I 278 Lot 1 280 Lot 2 263 Lot 2 265 Lot I 282 Lot 1 286 Lot I 285 Lot 2 263 Lot 2 267 Lot 2 270 Lot 2 269 Lot 2 270 Lot 2 272 Lot 2 272 Lot 3 278 Lot 2 274 Lot 2 275 Lot 3 277 Wotcr Content w=). JO 10 11 ‘18 12 14 15 13 14 14 13 11 11 12 9 12 11 14 13 13 Notes: 1) “Compaction Curve No,” refers to Table 8. 2) Unless otherwise noted elcvotionc shown ore to nearest foot. DfY Degree of Density Compaction u (%I 103.8~ 90 101 .s 80 106.3 93 101 .o 90 98.6 86 106.S 93 103.6 90 104.8 91 105.8 92 105.0 91 , 103.7 90 103.6 90 107.6 94 105.3 91 109.4 93 105.5 92 110.5 96 105.5 92 103.8 90 109.0 95 Compaction Curve No. Remorks 1 1 1 3 1 I 1 1 5 1 1 I 1 5 s 1 5 I 1 1 lest foiled,’ KO r3 Retest of 12 Test foiled, see 110 \ Retest of ‘5 I I I I I I / I I I I I I I , TABLE A - SUMMARY OF FIELD DENSITY TEST RESULTS (ASTM D1556-64 and/or ASTM 02922-71, ASTM 03017-72) Tot No. Dote of Test 21 9/l o/79 22 9/l o/19 23 9/l on9 24 9/l on9 25 9/l l/79 26 9/l lr/9 27 9/l lf79 28 9/l 1 /I9 29 9/l l/19 30 VIZ’9 31 9/12fi9 32 9/12/79 33 9/12/19 34 9/l 2/79 35 9/13n9 36 9/l 3/I9 37 9/13/79 38 9/13/79 39 9/14/19 40 9/14//9 Approximate Elevation Test Location (Feet) Lot 3 274 Lot 3 283 Lot 3 280 Lot 2 275 Lot 2 275 Lot 4 - Fill Slope 244 Lot 4 - Fill Slope 246 Lot 4 : Fill Slope 248 Lot 5 250 Lot 5 252 Lot 5 254 Lot 3 256 Lot 5 258 Lot 3 259 Lot 5 262 Lot 3 264 Lot 5 265 Lot 3 260 Lot 3 270 Lot 3 2R Woter Content w 13 13 16 12 14 17 .I2 16 16 13 II 14 14 10 12 11 11 16 16 13 DV Degree of Density Compoetiort (PCf) (%I 103.7 90 104.6 91 102.2 93 102.4 89 103.8 90 94.0 91 99.1 90 loo.4 91 loo.9 92 105.3 92 107.1 93 103.9 9d 105.3 92 104.1 90 104.1 90 103.5 90 103.6 90 104.2 90 104.9 91 lM.l 91 Compaction Curve No. Retirkt 1 1 4 1 fed foiled, see ‘95 1 Retest of 124 2 1 4 4 4 1 1 1 1 5 5 5 5 5 1 6 Notes: 1) “Compaction Curve No. ” refers to Table 8. 2) Unless othemire noted elevotionc shown ore to nearest foot. I / I / I I I I I , I I I I I I I 1 ! TABLE A - SUMMARY OF FIELD DENSITY TEST RESULTS (ASTM D 1556-64 and/or ASTM b2922-71, ASTM 03017-72) Test No. Dote of Test 41. 9/l 4f79 42 9/l 8f79 43 9/l 8/79 44 911 an9 45 9/l 8/79 46 9/l am 47 9/l s/79 48 9/19/19 49 9/l 9/79 50 9/l 9/?9 51 9/l 9/19 52 9/l 9/79 53 9/l 9/19 54 9/l 9p9 55 9/l 9/79 56 9/l 9/79 57 9/l 9/79 58 9/l 9/79 59 9/l 9/79 60 9/l 9/19 Approximate Woter Elevotion Content Test Location (Feet) &) Lot 3 Lot 8 Lot 8 Lot 9 Lot 8 Lot 9 Lot 6 Lot 3 Lot 3 lot 3 Lot 3 Lot 3 Lot 3 Lot 8 Lot 8 Lot B Lot a Lot 9 Lot 9 Lot 9 274 11 ’ 230 10 232 11 228 12 234 13 228 13 271 ‘11 274 9 276 IO 278 9 276 8 275 11 275 i0 233 13 235 14 213 16 233 15 225 11 225 19 226 14 b Degree of Density Compaction Compacfion (P4 W) Curve No. Remarks 105.4 102.0 102.3 98.5 107.6 106.3 102.8 102.5 101.5 102.2 104.2 103.3 1M.3 106.7 106.9 100.4 102.1 100.7 102.6 104.7 91 90 90 87 95 94 91 90 90 90 92 91 92 94 94 88 90 89 90 92 5 6 6 6 fed foilcd, see ‘46 6 6 Retest of 144 6 6 6 6 6 6 6 6 6 \ i b Test lolled, see f57 6 Retest of 156 6 Test foiled, see ‘59 6 Retest of 158 6 Notes: 1) “Compaction Curve No.” refers to Table 8. 2) Unless otherwise noted elevations shown ore to nearest foot. Test No. 61 62 63 64 65 66 67 68 69 70 71 R 73 74 75 76 77 70 79 80 I I I I / I / I I I I I I I I I 1 ~~, ,~ TABLE A - SUMMARY OF FIELD DtNSITY TfST RESULTS (ASTM 01556-M and/or ASTM 02922-71, ASTM 03017-72) _--. -- .- Dote of Test Test Locotton 9/t 9/79 Lot 9 9/20/19 Lot 4 9/20/79 Lo, 1 9/20//9 Lot 1 9/20/19 La, 9 9/10/79 Lot 4 9/2l/19 Lot 3 9/21/79 Lot 5 9/24/79 Lot 7 9/z s/79 lot 4 9/25/79 Lot 4 9/26/19 Cul De Sot (West End) 10/01/V Stam Droin Backfill Lot 3 10/01/79 Sram Drain Eockftll Ld 3 10/01/13 Storm Droin Bockfltl Lot 3 1 omm Entrance Rood - Lot 3 1 o/02/79 Entrance Rood - Lot 3 1 o/02/79 Entrance Rood - Lot 3 1 o/02/79 Entrance Road - Lot 3 1 o/03/79 Entrance Road - Lot 3 Approxlmote Water DV Elevolion Content Density (Feet) (%) (pet) 228 I6 103.9 231 14 103.8 287(FSG) to 112.3 288(FSG) 7 103.9 230 11 102.6 234 14 104.4 279 ,8 103.6 266 15 102.6 260 10 106.0 237 14 103.1 239 15 102.9 222(FSG)~ 11 103.2 281 12’ 103.5 280 13 104.4 279 12 105.1 283 9 105.3 204 13 104.6 206 14 102.5 289 17 103.9 292 to 104.0 Notes: I) “Compaction Curve No.” refers lo Table 8. 2) Unless othemise noted elevations shown ore to nearest foot. 3) “FSG” denotes finish subgrode etevotton. Degree of Compaction Compoc,ion (%) Curve No. 92 6 91 6 . 90 1 90 1 90 6 92 6 91 6 90 6 93 6 ’ 91 6 91 6 91 6 91 6 92 6 91 5 92 1 91 1 90 6 92 6 90 1 * . Remorks ~1 I I I I I I I I I I I I I I I I I I I I TABLE A - SUMMARY OF FIELD DENSITY TEST RESULTS (ASTM 01556-64 and/or ASTM D2922-71, ASTM D3017-72) 1 Test No. Dote of Test Approximotc Elevotion (Feet) 294 26B(FSG) 268(FSG) 239 28O(FSG) 2R41FS.G) 28l(FSG) 276(FfG) 276(FSG) 237(FSG) 237(FSG) 237(FSG) 276(FSG) 237(FSG) 231 (FSG) 24O(FSG) 231(FSG) Woter Dry Content Density Degree of Compaction W) 94 .93 94 91 92 w- 94 87 90 aa 88 86 91 90 07 94 92 Compaction CurYe ~NO. Rcmorks 61 1 o/03/79 82 10/03/19 63 1 o/03/19 a4 1 O/Mf79 85 1 o/09/19 86 1 Q/09/19 07 1 o/09/19 86 10/10/19 a9 1 O/l o/I9 90 10/10/79 91 1 O/l o/I9 92 10/l l/79 93 10/l l//9 94 10/l l/19 95 1 o/1,1/19 96 10/l l/79 97 10/12/19 Test Location Entrance Rood - Lot 3 Lot 5 Lot 5 Lot 4 Lot 6 Lot 3 Lot 3 Lot 2 Lot 2 Lot 8 Lot 3 Lot 8 Lot 2 Lot 8 Lot 9’ Lot 4 Lot 9 (PCf) ’ 13 108.5 14 lM.6 15 107.8 15 103.5 10 104.1 9 102.2 11 106.3 8 90.7 6 102.3 10 99.8 8 100.4 15 97.6 10 103.9 12 101.7 a 99.2 6 107.0 6 104.9 Notes: 1) “Compaction Curve No.” refers to Toblc 8. 2) Unless otherwise noted elevations shown ore to nearest foot. 3) “FSG” denotes finish subgrodc elevation. 1 1 1 6 6 6 6 6 6 6 6 6 6 6 6 6 6 Test foiled, see ‘93 Test foiled, see i94 Tot foiled, see I 94 Test foiled, see 194 Retest of I88 Retest dS ‘@a 90, 91 itI c Test ,folled, see 197 , Retest of ‘95 - TABLE B - LABORATORY COMPACTION TEST RESULTS (ASTiM 01557-70) - - - - - - - - - - - .- - Compaction Test Description of (Curve)No. Moteriol 1 SILTY SAND (SW, tan 2. CLAYEY ond SANDY SILT VW, ton 3 SILTY and SANDY CLAY (CL-CH), ton 4 SILTY and SANDY CLAY (CH), tat-, 5 SILTY SAND (SM), brown ~. 6 SANDY SILT W), tm source of Moteriol Onsite Onrite Onsite Onside Onside Onsitc Maximum Optimum Dry Density Woter Content (PCf) 6) 115.0 14.0 103.0 2i.3 112.0 15.9 110.0 15.7 115.5 13.5 113.5 14.0 .