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HomeMy WebLinkAboutCT 72-20; 3171 Venado Street Condominium Complex Unit 2; Soils Report Fourth Interim; 1986-12-04.- _ CATLIN ENGINEERING, INC. ->~;z:20 PO. Box 4225 La Mesa, California 92044-0970 vviikz (619) 588-8500 ,- Continental American Properties 1764 San Diego Avenue San Diego, CA 92110 ATTN: Ms. Carol Fox December 4, 1986 Subject: Project No. 2OC5C Fourth Interim Report of Compacted Filled Ground Proposed Condominium Complex 3171 Venado Street Carlsbad, California -. Gentlemen: We refer to our First Interim Report of Compacted Filled Ground dated March 12, 1986, Second Interim Report of Compacted Filled Ground dated October 9, 1986, Third Interim Report of Compacted Filled Ground dated November 3, 1986, and to two reports by Benton Engineering, Inc, Final Report of Compacted Filled Ground, dated November 27, 1974 and Site Inspection and Recommendations for Construction, dated July 22, 1981. This report records our observations and the results of tests we performed in connection with our inspection of the compaction of filled ground placed on certain areas of the subject property. This property is more particularly referred to as Assessors Parcel No. 223-190-05, -06, -07, and -08 in the City of Carlsbad, County of San Diego, State of California. The grading reported herein was accomplished during the period from November 4 through November 26, 1986. The elevations of fill (or depth below subgrade in the case of storm drain trench backfill) at which the tests were taken and the final test results are presented on pages T-15 through T-19, under "Table of Test Results." The laboratory determinations of the maximum dry density and the optimum moisture content of the fill soils are set forth on page L-l u der "Laboratory Test Results." r The approximate location of the filled ground and the field density tests are presented on Drawing Nos. 3, 4, 6, and 7 entitled "Approximate Location of Compacted Filled Ground." - The results of our tests and observations indicate that the soils placed on subject site under our inspection have been compacted to at least 90 percent of maximum dry density except 40 feet'of storm drain trench as shown on drawing No. 4. This length of storm drain trench is to be compacted at a later date. .- Soil compacted to 90 percent will support the proposed building structure(s) without detrimental settlement, if the foundations are placed at least 5 feet back from the top of slope. Foundations, fences, edges of slabs, or paved surfaces placed closer to the top of slope than five feet could suffer differential movement as a result of the inherent poor lateral stability of soils near the top of a slope. In this zone, foundations should be deepened such that the face of the foundation where it bottoms is at least five feet back from the face of slope at that level. (Please refer to Appendix E). Consulting Engineersand Geologists PAGE 2 CONTINENTAL AMERICAN/VENADO STREET 2OC5C DECEMBER 4, 1986 At the completion of grading, vertical cut slopes with a maximum height of approximately 17 feet existed on the site. We judge that these cut slopes will be stable against massive slope failure for a limited period of time, say two to four weeks, after which they should be supported by retaining structures. Special care should be exercised to assure that no water is allowed to saturate the slopes either from natural or artificial sources. Further, no worker should be permitted between these slopes and any retaining structure because vertical cuts are subject to sloughing. Some of the fill soils encountered on the site were considered to be critically expansive. In order to minimize the detrimental effects of these expansive soils on the structures, we recommend that the provisions of Appendix CCC be adhered to. Alternatively, the post tension design for floor slabs which was presented to us during earlier phases of this development will mitigate the detrimental effects of expansive soil at least as well as the design described in our Appenix CCC. Please note that the recommendations in Appendix CCC anticipate conventional financing. Please notify us for alternative recommendations if the project is to be FHA or VA guaranteed. A safe allowable soil bearing measure of 1650 pounds per square foot may be used as set forth in the above mentioned report of Site Inspection and Recommendations for Construction. We observed that the soils encountered during grading did not differ substantially from those anticipated by the above mentioned reports. Please be aware that proper control of the site drainage and continuous maintenance of all drainage facilities is an important factor related to the overall stability of foundations as well as the stability of cut and fill slopes. We therefore recommend that you direct any surface runoff away from foundations and slopes and to the street or drainage facilities without intermediate ponding. Drainage should be maintained such that surface waters are not permitted to flow over the top of any exposed slopes. We further recommend that we be authorized to revi.ew the design of foundations and to inspect any further grading and the construction of foundations in order to assure that our recommendations hpve been understood. Seemingly minor variations between our recommendations and the construction can result in essentially nullifying their advantageous effects. This would result in a waste of the engineering, time, money, and materials. If the work is not inspected by us, we offer no assurance of adequate foundation performance or that any of our conclusions relating to soil stability may be relied upon. - - . . PAGE 3 CONTINENTAL AMERICAN/VENADO STREET 2OC5C DECEMBER 4, 1986 Pages T-15 through T-19 and L-l, Drawing Nos. 3, 4, 6 and 7, and Appendices CCC and E are parts of this report. The opportunity to be of service is sincerely appreciated. Respectfully submitted, C;.~G~ - Mark B. Cadin, Civil Engineer Distr. (2) Addressee MBC:LAB/waw/A - - PAGE L-l CONTINENTAL AMERICAN/VENADO STREET 2OC5C DECEMBER 1, 1986 REVISED: DECEMBER 4, 1986 - LABORATORY TEST RESULTS The maximum dry density and optimum moisture contents of the soils as determined by the ASTM D1557-70 method, that uses 25 blows of a 10 pound rammer falling from a height of 18 inches on each of 5 layers in a 4 inch diameter l/30 cubic foot compaction cylinder, are presented as follows: -. - Soil Soil Type Description - A B C - D E F .- - - G H I J K M N Light Yellow Brown Fine to Medium Sand 120.9 9.8 Gray Tan silty Clay Red Brown Very Fine to Coarse Clayey Sand Green With Red Streaks Silty Clay Medium Brown Silty Fine Sand With Clay Binder Tan Yellow silty Clay Light Irown-Orange clayey Fine to Coarse Sand Olive Brown Fine to Medium Clayey Sand Gray Silty Fine to Coarse Sand (Import) Gray Brown Silty Fine to Coarse Sand (Import) Brown Clayey Fine to Coarse Sand Brown Silty Fine to Coarse Sand (Import) Tan Clayey Silty Fine to Medium Sand (Import) Medium Brown Gray Fine to Medium Sandy Clay Maximum Dry Density lb/cu.ft. 113.8 127.8 Optimum Moisture Content % Dry Wt. 16.4 9.5 106.3 15.4 122.9 12.0 120.4 13.0 122.6 12.7 118.4 14.0 137.4 6.9 138.6 1 133.1 125.5 7.2 8.9 8.7 115.0 15.0 120.5 13.3 - -~ - - - .- - - - - - - - - - - PAGE T-15 CONTINENTAL AMERICAN/VENADO STREET 2OC5C DECEMBER 1, 1986 REVISED: DECEMBER 4, 1986 TABLE OF TEST RESULTS Field Density Tests were performed in accordance with the applicable provisions of the current ASTM Standard 01556 and the results are presented below. Test No. 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 Location Test of Test Elevation LOT 282 FG/243.0 II FG/244.0 LOT 283 S.G. II S.G. II S.G. LOT 278 227.0 LOT 279 -3.5 LOT 278 229.5 I, 230.0 II 230.5 LOT 277 FG/235.0 LOT 277 231.0 II 235.0 II 235.0 ,I 238.0 II 238.0 LOT 278 FG/232.5 II FG/232.5 LOT 277 FG/237.5 VISTA BONITA 264 STA 3t20 BASE Field Dry Moisture Density % Dry Wt. lb/tuft 12.7 122.9 8.3 120.7 11.7 121.7 7.9 127.1 7.0 122.0 11.9 123.3 14.3 118.2 15.5 112.0 15.0 110.0 17.4 109.9 18.9 104.2 18.6 106.9 18.1 113.7 16.2 112.3 15.1 114.7 17.9 118.4 11.0 131.7 18.0 118.1 20.2 104.4 5.5 135.8 . . . Soil Type J J B B B J G F L L A L A A G G J G A Ii Compac- Test tion % Date Remarks 92.3 10-23-86 90.7 u 95.2 10-31-86 99;5 u 95.5 o" 92.7 w 99.9 It 91.4 11-01-86 95.7 w 95.8 ' 91.6 ” 93.0 lo 97.9 ” 98.7 ” 96.9 It 97.8 ” 98.9 11-03-86 99.7 ” 91.7 11-04-86 98.8 ” .- - - .- - - - - - - - - - - - PAGE T-16 CONTINENTAL AMERICAN/VENADO STREET 2OC5C DECEMBER 4 1986 REVISED: DECEMBER 4, 1986 TABLE OF TEST RESULTS Field Density Tests were performed in accordance with the applicable provisions of the current ASTM Standard D1556 and the results are presented below. Test Location Test No. of Test Elevation VISTA BONITA 265 STA 1+50 BASE 266 STA 3t20 BASE 267 STA 2t25 BASE 268 STA Ot88 BASE 269 LOT 277 236.0 STORM DRAIN 270 LOT 279 -2.0 STORM DRAIN 271 LOT 279 -2.0 272 LOT 278 228.0 STORM DRAIN 273 LOT 279 FG STORM DRAIN 274 LOT 279 FG 275 LOT 278 230.0 276 LOT 277 234.0 277 LOT 297 232.0 278 LOT 277 232.0 STORM DRAIN 279 LOT 279 -3.0 280 LOT 280 236.0 281 LOT 277 FG/237.5 282 ” FG/237.5 Field Moisture % Dry Wt. Dry Density lb/tuft 5.5 133.7 7.8 134.8 5.7 134.9 6.0 135.9 19.3 108.2 15.1 112.1 15.2 110.6 16.4 117.2 15.8 114.0 18.5 112.0 22.5 115.7 19.2 115.4 13.8 114.4 13.1 115.4 13.6 107.1 15.3 128.2 12.6 120.8 15.5 123.5 . Soil Type H H H H G G G G G G G G G G G J J J Compac- Test tion % Date Remarks 97.3 11-04-86 98.1 ’ 98.2 ’ 98.9 ” 91.4 11-05-86 94.7 11-06-86 93.4 " 99.0 In 96.3 11-07-86 94.6 " 97).7 " 97.4 " 96.6 11-10-86 97.5 " 90.5 u 96.3 11-11-86 90.7 w 92.8 " - .~.~ - - - - - - - - - - - - - - - - PAGE T-17 CONTINENTAL AMERICAN/VENAOO STREET TABLE OF TEST RESULTS 2OC5C DECEMBER 1, 1986 REVISED: DECEMBER 4, 1986 Field Density Tests were performed in accordance with the applicable orovisions of the current ASTM Standard D1556 and the results are presented below. Test Location Test of Test Elevation No. 283 284 285 286 287 288 289 I, FG/237.0 II FG/237.0 LOT 276 261.0 II 263.0 LOT 278 232.5 ,I FG/234.0 II FG/234.0 290 291 292 293 294 295 296 297 298 299 300 301 302 STORM DRAIN LOT 280 -6.0 LOT 275 274.5 II 276.5 LOT 278 232.0 II FG/232.0 II FG/234.0 LOT 276 265.0 10 FG/266.0 II FG/266.0 LOT 274 276.5 II 278.5 II 279.0 II 280.0 Field Dry Moisture Density % Dry Wt. lb/tuft 14.5 124.3 15.5 120.5 16.2 116.5 17.1 116.9 13.6 127.0 16.5 109.5 12.9 115.6 16.2 117.1 12.5 107.4 15.7 108.8 11.3 110.1 18.6 106.8 10.1 117.1 11.2 122.4 12.3 122.6 12.2 124.4 14.6 119.7 13.5 119.6 16.1 114.9 16.1 110.7 .- Soil Type J J G G J G G G G G G G G J J J J J G G Compac- Test tion % Date Remarks 93.3 n 90.5 It 98.4 11-11-86 98.7 ' 95.4 11-12-86 92.5 os 97.6 ' 98.9 ' 90.7 11-13-86 91.9 l” 93.0 11-14-86 90.2 I4 43.9 n 92.0 n 92.1 11 93.5 IN 90.0 n 90.0 n 97.0 11-17-86 93.5 11-19-86 - .- - - - - - - - - - - - - - - PAGE T-18 CONTINENTAL AMERICAN/VENADO STREET 2OC5C DECEMBER 1, 1986 REVISED: DECEMBER 4, 1986 TABLE OF TEST RESULTS Field Density Tests were performed in accordance with the applicable ;;y;;sions of the current ASTM Standard D1556 and the results are presented Test No. 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 Location of Test II II LOT 274 II II " " II " II II ,I " LOT 275 II II II LOT 276 II I, Test Elevation 279.5 FG/281.0 FG/281.0 FG/281.0 276.0 278.0 278.0 FG/279.0 FG/279.0 FG/280.0 FG/281.0 FG/280.0 FG/280.0 277.0 FG/278.0 FG/278.0 FG/278.0 258.0 260.0 260.0 STROM DRAIN LOT 278 -4.0 Field Dry Moisture Density % Dry Wt. lb/tuft 17.2 108.9 17.9 114.2 14.6 116.8 14.5 127.6 17.8 118.0 16.9 111.0 20.0 102.7 17.1 102.4 24.0 101.9 15.8 115.0 17.4 112.9 17.0 111.6 18.4 110.5 10.5 106.4 18.2 102.3 17.5 112.4 13.8 114.4 14.0 114.7 11.0 113.5 15.5 108.4 10.2 108.4 Soil Type G G G J G G A A C G G A A A A G G G G G G Compac- Test tion % Date Remarks 92.0 m 96.4 ' 98.7 11-19-86 95.9 VI 99.7 ” 93.8 11-20-86 90.2 ” 90.0 11-21-86 95.8 " 97.2 " 95.4 " 98.1 ” gv ” 93.5 11-24-86 90.0 n 95.0 n 96.6 ” 96.9 ’ 95.9 11-25-86 91.6 ’ 91.6 ’ - - - - .- - - - - - - - - - - - - PAGE T-19 CONTINENTAL AMERICAN/VENADO STREET 2OC5C DECEMBER 1, 1986 REVISED: DECEMBER 4, 1986 TABLE OF TEST RESULTS Field Density Tests were performed in accordance with the applicable provisions of the current ASTM Standard D1556 and the results are presented below. Test Location Test No. of Test Elevation 324 LOT 276 FG/261 .O 325 LOT 276 FG/261.0 326 ” FG/261 .O 327 ” FG/265.5 STORM DRAIN 328 LOT 278 -2.0 329 LOT 275 282.5 330 Ia 282.0 331 LOT 276 FG/265.5 STORM DRAIN 332 LOT 278 -2.0 STORM DRAIN 333 LOT 278 FG 334 LOT 280 197.0 Field Moisture % Dry Wt 14.6 15.3 12.5 17.8 Dry Density lb/tuft 111.6 118.0 116.4 102.5 18.3 99.7 16.0 109.5 16.1 110.3 13.7 107.9 10.9 107.4 16.9 115.8 14.6 113.5 Soil Type G G G G Compac- Test tion % Date Remarks 94.3 Ii 99.7 11-25-86 98m.3 " 86.5 ’ FAILED SEE 331 84.2 ’ FAILED SEE 332 92.4 " 93.2 u 91.1 11-26-86 RETEST OF 327 90.7 ” RETEST OF 328 97.8 " 95.9 Ia 1 - - CATLIN ENGINEERING, INC. CONSULTING ENGINEERS AND GEOLOGISTS P.O. Box 4225 La Mesp. California 92044-0970 (619)588-8500 - - - - - - APPENDIX CC RECOMMENDED PROCEDURES RE: EXPANSIVE SOILS The following recommendations apply to conventionally financed residential construction. If you anticipate FHA or VA financing, please contact us for the necessary special recommendations. For soils that are expansive with respect to change in moisture content, there is no economical way to absolutely prevent movement if there is a change in soil moisture content. Insofar as it is practicable, a stable soil moisture content should be established and maintained throughout the life of the structures. However, it is usually not practical to maintain a completely stable soil moisture content. Therefore, in order to minimize the undesirable effects of expansive soils on structures, if these soils are placed or allowed to remain within the upper 3 feet below finish grade, we recommend that the following special precautions be exercised in design and construction of slabs and foundations. a. b. C. Avoid the use of isolated interior piers. Continuous interior and exterior footings should be used throughout and these should be placed at a minimum depth of 24 inches below the lowest adjacent exterior final ground surface. We note especially that these continuous footings should run across door openings such as garage doors and person doors. Reinforce and inter-connect continuously with steel bars all interior and exterior footings with one #5 bar at 3 inches above the bottom of all footings and one'#5 bar placed 1 l/2 inches below the top of the foundation stems for frame floors or top of slab for slab-on-grade construction. Insofar as practicable, maintain the moisture at 1 to 4 percent greater than optimum in the soil below the building to a depth of 3 feet below finish grade prior to placing concrete. Please note that large amounts of moisture should not be added immediately prior to placing the concrete. This will result in expansion of the soil against the uncured concrete which would cause damage. - - - - PAGE 2 APPENDIX CC CATLIN ENGINEERING, INC. - d. .~ - - e. f. 9. In buildings where it is practicable to permit independent movement of slabs relative to the foundations, such as in garages and warehouses, these slabs should be separated from the foundations by l/2 inch thickness of construction felt or equivalent. Special care should be exercised to assure that the separation extends to the full depth of the thickened edges of slabs and that door stops attached to the building be clear of the slab by at least 1 inch. Use raised self-supporting floors that s an between continuous footings or reinforce all concrete slabs on gra e with #4 bars at 32 inches on c! centers each way. Provide a minimum of 4 inches of clean sand beneath all concrete slabs. Provide a moisture barrier 2 inches below slabs in areas that receive flooring which might be adversely affected by capillary moisture. Positive drainage should be provided away from all perimeter footings. Positive drainage is defined as a slope of 2 percent or greater (2 feet fall per 100 feet) away from the foundations for at least 5 feet, drainage should then be directed by swales that fall at 2 percent or greater to the street or some other collective drainage system. - - - - --n PROPCXiED S-I-R,C)C-TURE: TOP OF COMPACTELD FILL 3LOPh COMPACTED FIUw3LOat RF-COMMENDATION5 OF THE A RCWITECT OR ~TUCTVRAL ENGIINEIZ TYP!r,AL 3ECTION (3Ht?W\Nr; PptOPO3ELO FDUNDAT:ON LOCATED WlTUlN FIVE FEET OF TOP OF COMPACTED FILL SLOPE >