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HomeMy WebLinkAboutm30289fDONALD R. WARREN CO. ENGINEERS 930 W.SUNSET BOULEVARD LOS ANGELES, CALIFORNIA 90012 626-0101 Job No. F65-174 F I M LL L Date 10/13/66 REPORT ON COMPACTION Sheet 1 of n289 Lots Ccnplete Tract and offsite Area Tractlo. Location Diamond Bar Blvd. and Shadow Canyon Dr., Diamond Bar, Calif. Client Transamerica Development Company Ciient'sAddress 2900 Brea Carryon Road; Diamond Bar, California Engineer Dutch Holzhauex' Erig r. , Inc Contractor StrecKer General: Type of Soil. Native Sand, Silt, Clay, Siltstone and Sandstone Mixtures Imported None Before placing fill the existing surface was stripped of vegetation, scarified, watered as required, and com. pacted. Inspection of the stripped surface indicated the area to be original ground. The determination of voidsorgeologicweaknessesisnotincludedinthescopeofthisreport. Where natural slopes existed, benches werecutintotheslopesasthefillsprogressed, to provide a firm bond between natural ground and the compacted fill. The fill was placed in Iayers 6 to 8 inches in thickness, watered and compacted by sheepsfoot rollers and controlled routing of earth —moving equipment. Inspections and field density tests were made by the Donald R. Warren Co. during the progress of the job. The results and estimated locations of tests and limits of compacted areas are attached as part of this report. Special Conditions: Reference is made to the Engineering Reports (F 65-174) related to the development of the subject tract prepared by the Donald R. Warren Co. and the Geologic Reports prepared by James E. Slosson and Associates. Trees-, roots, trash and debris were removed from the subject site. re All excavations fill. dNoingotherVe clearanceobstructionsT, esurfaceght or subsurface, rade with compacted were encountered. SF `.CIAL CONDITIONS Continued on Page 2 - Recommendations. On the basis of inspection during grading, attached results of field density tests at selected points. and results of stability tests on the soil types used, it is our opinion that the compacted areas are adequate for design loads of 130 pounds per square foot for residential footings, square or continuous, placed inches below finished grade. Note: A warranty is not implied, nor should one be construed. Respectfully submitted RC—JF/DRC/93 DONALD R. WARREN CO. Distribution: Transamerica Develoument Company By 2 - L.A. County Bldg. and Safety Div. 1 - Dutch Holzhauer lingr. Inc e. w. certificate - 1 - Jari-s E. Slos4on and ssoc. Review by DONALO R. WARREN ENGINEER! Job No. F65 -17 4 Cl-sent Tract No. Test No. Transamerica Development Comnan 30289 RESULTS OF FIELD DENSITY TESTS Date 10/1-3/66 Sheet 2 of Field Moisture Field Density Maximum Density Percent Percent Lbs./Cu. Ft. Lbs./Cu. Ft. Maximum SPECIAL CONDITIONS, Continued - Poorly consolidated soils and alluvium were removed to firm natural soil or bedrock prior to placing compacted fill. Subdrains were constructed at the contact between the cleaned canyon bottoms and the compacted fill. Elevations and types of Subdrains were determined in the field during inspection by representatives of Dr. James E. Slosson, the tract geologist, and Donald R. warren Co. Compacted fill buttresses were constructed to the estimated limits shown on the attached figure against portions of the cut slopes descending to the streets from Lots 2, 6, 7, 9-18, 52-56 inclusive, and the rear portion of Lots 66-68 inclusive. Subdrains were incorporated into the compacted fill buttress at the contact with the natural ground. Elevations and types of subdrains were determined in the field. To restrict the infiltration of landscape water into the underlying bedded material, the level cut area of Lots 19-21, 24-28 inclusive, 63 and 70 were undercut 30+ inches and the material was replaced as a compacted fill blankeF. Compacted fill was placed on Lots 1-21, 24-36, 40, 41, 47--64 and 66-70 inclusive to facilitate the grading and placement of the adjacent stye,=ts. The major portions of the lots were left at natural grade. Compacted fill was placed in canyons, adjacent to the streets and offsite to the tract, to bring the areas up to are elevation to provide adequate lot drainage to the streets. It is suggested that the following general conditions be observed with reference to proximity of footings to the compacted edge of fill slopes: Minimum Distance of Footing Vertical Height from a 1 on 1--1/2 plane of 1-1/2:1 Slope Projected Upward from Toe of Slope 0 to 5 feet 3 feet 5 to 20 feet 5 Feet Over 20 feet 10 feet Field Investigation: Field density tests were taken at locations shown, according to A.A.S.H.O. Standard Test lllethod T 147-49. Bag samples of representative fill materials were obtained for laboratory tests. and the driven —ring undisturbed sample method. Laboratory Tests: llloisture determinations were made on sealed samples from each field test. Compaction tests were performed on representative soils according to A.S.T.M. Standard Test Method D 698.57T, modified to use 25 blows of a 10•pound hammer falling 18 inches on each of 3 layers in a 4-inch diameter cylindrical mold of 1 / 30 cubic foot volume. DONALD R. WARREN ENGINEKR5 obNo.F 65'-"174 Client Transamerica Development Company Date 10-13-66 Tract No. 30289 Sheet 3 of RESULTS OF FIELD DENSITY TESTS Test Field Moisture Field Density Maximum Density Percent No. Percent Lbs./Cu. Ft. Lbs./Co. Ft. Maximum SPECIAL CONDITIONS, Continued - Minimum Distance of Footing Vertical from a 1 on 2 plane Height of 2:1 Slope Projected Upward from Toe of Slope 0 to 20 feet 3 feet Over 20 feet 5 feet If plans call for encroachment, it is our opinion that the footings should be deepened to conform to the above. Adequate measures to provide proper slope protection and drainage should be constructed in accordance with the grading ordinance, as the above recommendations assume full lateral support of the compacted fill. The surfaces of the compacted fill slopes were trimmed back or gridrolled and tests indicate a firm compacted surface was obtained. Basic Soil Type (Without Rock) Laboratory) Optimum Moisture in Percent 14.1 13.5 13.2 14.7 20.0 19.8 16.7 9.9 11.2 13.6 13.8 13.6 11.3 17.5 18.0 20.2 13.6 Maximum Density P. C. f . 110 112 113 107 97 99 103 120 116 108 106 109 117 102 101 97 109 Field Investigatign: Field density tests were taken at locations shown, according to A.A.S.H.O. Standard Test Method T 147.49. Bag samples of representative fill materials were obtained for laboratory tests. and the driven —ring undisturbed sample method. Laboratory Tests: Moisture determinations were made on sealed samples from each field test. Compaction tests were performed on representative soils according to A.S.T.M. Standard Test method D 698-57T, modified to use 25 blows of a 10-pound hammer falling 13 inches on each of 3 layers in a 4-inch diameter cylindrical mold of 1/30 cubic foot volume. GONALO R. WARREN NGINE£R9 Client Trancamerica Development Company Tract No. 30289 Test No. SPECIAL CONDITIONS Continued - RESULTS OF FIELD DENSITY TESTS Field Moisture Field Density Percent Lbs./Cu. Ft. Continued — JobNo. F 65-174 Date 10-13-66 Sheet 4 oft Maximiun Density Percent Lbs./Cu. Ft. Maximum Basic Soil Type (Without Rock) Laboratory) Optimum Moisture in Percent 10.0 15.4 13.0 14.7 14.9 13.2 Maximum Density P. C. f. 116 107 110 107 105 ill It should be noted that this report is concerned only with the compaction of fills during the rough grading of the tract; future cutting, filling or terracing to create level pads should be done under the inspection of a qualified soils engineer. Reference to our Job No. F 65-174 would help materially in re-establishing the complete file. The results of swell tests made on samples of the soil types which might affect foundation design, remolded to 90 percent of maximum density at a moisture content at or below the shrinkage limit or 80 percent of optimum moisture whichever is lower and immersed in water for 24 hours, are as follows: Sample No. Soil Classification 1 Sandy Clay lu Silty Clay 15 Clayey Siltstone 16 Siltstone 1'7 Sandy Clay 18 Sandy Silt Clay Percent Swell Under 60 p.s.f. Loading 2.8 8.0 4.8 6.1 7.3 6.1 FECIAL CONDITIONS Continued on Page 5 - Percent Swell, Under 650 p.s.f. Loading 0.4 2.1 0.9 1.6 o.8 0.5 Field Investigation: Field density tests were taken at locations shown, according to A.A.S.H-0. Standard Test Method T 147-49! Bag samples of representative fill materials were obtained for laboratory tests. and the driven —ring undisturbed sample method. Laboratory Tests: Moisture determinations were made on sealed samples from each field test. Compaction tests were performed on representative soils according to A.S.T.Al. Standard Test Method D 69S-57T, modified to use 25 blows of a 10-pound hammer falling 13 inches on each of 3 layers in a 4-inch diameter cylindrical mold of 1 /30 cubic foot volume. t)ONALD R. WARREN ENGINEERS Job No. F 6 5 -17 4 Client Transamerica Development Company Date 10-13-66 Tract No. 30289 RESULTS OF FIELD DENSITY TESTS Test Field Moisture Field Density No. Percent Lbs./Cu. Ft. SPECIAL CONDITIONS, Continued - Sheet 5 of Maximum Density Percent Is./Cu. Ft. Maximum Eased upon the results of the swell tests, Sample No. 1 is considered to be slightly expansive under slab loads and non - expansive under footing loads; Sample Nos. 14 and 16 are considered to be moderately expansive under slab and footing loads; and Sample Nos. 15, 17 and 18 are considered to be moderately expansive under slab loads and slightly expansive under footing loads. The following is the recommended procedure concerning the treatment of subgrade soils and residential footings where slightly expansive soils exist: 1. All footings for single story residential dwellings should bear at least 12 inches below finished grade, and continuous footings should be used under all bearing partitions. All footings should be reinforced with No. 4 bars running continuously, one in the top of the stem wall and one in the bottom of the footing. 2. Positive drainage should be provided away from the structure. 3. Gutters and downspouts will not be required unless adverse drainage conditions exist contrary to Item 2 above. Where slab construction is planned, the following treatment is recommended in a dit on to theforegoing: 4. House and garage slabs should be reinforced with 6 x 6 -- 10/10 welded wire fabric or equivalent reinforcing steel. 5. If conventional financing is used, a moisture barrier should be provided beneath the slab within the living area, either in the form of a barrier membrane such as Viscueen or a capillary break base course having a minimum thickness of 4 inches. If the base course is selected, the material should consist ofcrushed rock of maximum one -inch size. If FHA or VA insured financing is used, a moisture barrier will be required in accordance with their standards. The following is the recommended procedure concerning the treatment of subgrade soils and residential footings where moderately expansive soils exist: Field Investigation: Field density tests were taken at Iocations shown, according to A.A.S.H.O. Standard Test Method T 147-49. Bag samples of representative fill materials were obtained for Iaboratory tests. and the driven —ring undisturbed sample method. Laboratory Tests: Moisture determinations were made on sealed samples from each field test. Compaction tests were performed on representative soils according to A.S.T.M. Standard Test Method D 698-57T, modified to use 25 blows of a 10-pound hammer falling 18 inches on each of 3 layers in a 4-inch diameter cylindrical mold of 1/30 cubic foot volume. OoNALD R. WARREN ENGINEERS Job No. F 6 5 -17 4 Client Transamerica Development Company Tract No. 30289 RESULTS OF FIELD DENSITY TESTS Test Field Moisture No. Percent SPECIAL CONDITIONS, Continued - Field Density Lbs./Cu. Ft. Date 10--13-66 Sheet 6 of Maximum Density Percent Lbs./Cu. Ft. Maximum 1. All footings for single story residential dwellings should bear at lea t 12 inches below finished grade, and continuous footings should be used under all bearing partitions. All footings should be reinforced with No. 4 bars running continuously, one in the top of the stem wall and one in the bottom of the footing. 2. Positive drainage should be provided away from the structure. Gutters and downspouts will not be required unless adverse drainage conditions exist contrary to Item 2 above. Where slab construction is planned, the following treatment is recommended in addition to the foregoing: 4. House slabs should be reinforced with 6 x 6 - 10/10 welded wire fabric or equivalent reinforcing steel. 5. Garage slabs should be reinforced with 6 x 6 -- 10/10 welded wire fabric or equivalent reinforcing steel and should be cast independently of the stem wall. A positi-ie separation of expansion joint material should be provided between the slab and the stem wall. 6. If conventional financing is used, a moisture barrier should be provided beneath the slab within the living area, either in the form of a barrier membrane such as Visqueen or a capillary break base course having a minimum thickness of 4 inches. If the base course is selected, the material should consist of crushed rock of maximum one -inch size. If FHA or VA insured financing is used, a moisture barrier will be required in accordance with their standards. 7. The soils beneath all slabs should be wetted sufficiently to obtain a moisture content well in excess of optimum to a depth of 18 to 20 inches below subgrade. 8. The depth of penetration of the water should be checked by a qualified soils engineer prior to placing concrete, since the depth of penetration is critical. The addition of detergent to reduce surface tension would increase the rate of penetration. Field Investigation: Field density tests were taken at locations shown, according to A.A.S.H.O. Standard Test Method T 147.49 *Bag samples of representative fill materials were obtained for laboratory tests. and the driven —ring undisturbed sample method. Laboratory Tests: Moisture determinations were made on sealed samples from each field test. Compaction tests were performed on representative soils according to A.S.T.M. Standard Test Method D 698-57T, modified to use 25 blows of a 10-pound hammer falling 18 inches on each of 3 layers in a 4-inch diameter cylindrical mold of 1 /30 cubic foot volume. Client DONALO R. WARREN ENGINEERS Transamerica Development Company Job No. Date F 65-174 10-13--66 Tract No. 0289 Sheet 7 of RESULTS OF FIELD DENSITY TESTS Test Field Moisture Field Density Maximum Density Percent No. Percent Lbs./Cu. Ft. I.bs./Cu. Ft. Maximum SPECIAL CONDITIONS, Continued Io special foundation reQu. rements are necessary where non -expansive sons exist. Since the lots were left at natural grade and no specific building areas were constructed at this time, it is recommended that upon completion of grading of the individual pad areas, a qualified soils engineer check each lot for the degree of expansiveness of the soils TESTS, hollowing Pages Field Investigation: Field density tests were taken at locations shown, according to A.A.S.H.O. Standard Test Method T 147.49. 13ag samples of representative fill materials were obtained for laboratory tests. and the driven —ring undisturbed sample method. Laboratory Tests: Moisture determinations were made on sealed samples from each field test. Compaction tests were performed on representative soils according to A.S.T.M. Standard Test Method D 698-57T, modified to use 25 blows of a 10-pound hammer falling 18 inches on each of 3 layers in a 4-inch diameter cylindrical mold of 1/30 cubic foot volume.