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HomeMy WebLinkAboutTract Map 22916-1 Lot 75 Geotechnical Report • ® PACIFIC SOILS ENGINEERING, INC. (c�D TELEPHONEN(619I TY R0560-1713, FAX:AN DIEGO,(619) 560-0380 CALIFORNIA92111 E G 993TAYCO ECULA ENT% Costain Homes620 Newport Center Drive - Suite 400PART Newport Beach, CA. 92660 August 24 , 1993 Work Order 400157AG Attention: Ms. Susan Lindquist Subject: Precise Grading Report for Lot 75, Vintage • Hills Recreation Center, Tract 22916-1, in the City of Temecula, California References: See Appendix • Gentleperson: This report presents geotechnical data and testing results per- taining to the completion of precise grading and erosion repair • for lot 75 of the Vintage Hills Recreation Center, Tract 22916-1, in the City of Temecula, California. This grading was completed in June, 1993 . Data developed during rough, precise grading and erosion is sum- marized in this report, on Table I and the enclosed 20-scale pre- cise grading plans dated October 30, 1990 prepared by Robert Bein, William Frost and Associates, Inc. Also presented herein • are the foundation and slab design recommendations based upon field and laboratory testing of as-graded soil conditions. All cuts, fills and processing of original ground covered by • this report have been completed under Pacific Soil Engineering, Inc. Is (PSE) observation and testing. Accordingly, the grading is considered to be in compliance with the City of Temecula grad- ing code criteria and the reference reports. • CORPORATE HEADQUARTERS LOS ANGELES COUNTY OFFICE RIVERSIDE COUNTY OFFICE SOUTH ORANGE COUNTY OFFFICE • (7 14) 220-0770 (213)325-7272 o, 775-6771 (714) 358-0154 (7 14) 730-2122 FAX: (714) 220-9589 FAX: (213)325-8854 FAX: (714) 358-0592 FAX: (714) 7305191 • Work Order 400157AG Page 2 August 24 , 1993 • Completed work has been reviewed and is considered suitable for • the construction now planned. Slopes are considered surficially and grossly stable and should remain so under normal condi- tions. To reduce exposure to erosion landscaping of all grading slopes should be accomplished as soon as possible. Drainage • berms and swales should be established and maintained to aid in drainage and long term .slope protection. • • • • • • • PACIFIC SOILS ENGINEERING, INC. • Work Order 400157AG Page 3 August 24 , 1993 • ENGINEERING GEOLOGY • Surficial Units Surficial units encountered during grading include soil and • alluvium. Soil consisted of dry and porous, medium brown sand and silty sand. The soil was stripped to Pauba Formation prior to fill placement. Alluvium consisted of light to medium brown, silty to clayey sand. Alluvium was removed to Pauba Formation • prior to the placement of artificial fill. Bedrock Unit Bedrock encountered during grading is assigned to the Pauba Form- ation and consisted of reddish-brown to tannish-brown siltstone and sandstone. The Pauba Formation is generally massive and flat-lying. Minor silt/clay intervals were observed in the bed- rock unit. • Faults No faults were observed in exposures during grading of lot 75 of Tract 22916-1. • Subdrains Subdrains were not placed during project grading due to the granular nature of onsite materials, gently sloping topography • and since the majority of the lot was cut. • • PACIFIC SOILS ENGINEERING, INC. • Work Order 400157AG Page 4 August 24 , 1993 • Corrective Grading • No corrective grading such as buttresses or stabilization fills were recommended during the course of grading lot 75, Tract 22916-1. • Conclusions From an engineering geologic viewpoint, lot 75 of Tract 22916-1 is considered suitable for the intended use. • • • • • • PACIFIC SOILS ENGINEERING, INC. • Work Order 400157AG Page 5 August 24 , 1993 • SOIL ENGINEERING • A. PROJECT GRADING • 1. Compaction test results are presented in Table I and approx- imate locations of tests are shown on the accompanying pre- cise grading plans prepared by Robert Bein, William Frost and Associates, Inc. (sheets 1 and 2 of 3) . • Prior to placement of compacted fill, the exposed surface was scarified, watered as necessary and compacted in-place to project specifications. • 2 . Fill consisting of the soil types indicated in Table I was then placed in thin lifts, watered as necessary and compact- ed in-place to a minimum of 90 percent of the laboratory •. standard (ASTM:D 1557-78) . This was accomplished by utiliz- ing self-propelled, rubber-tired compactors, sheepsfoot com- pactors and heavy earth moving equipment. Each fill lift was treated in a like manner. • 3 . Fill placed on slope gradients steeper than 5-horizontal to 1-vertical was keyed and benched into bedrock. The upper soils were stripped off and benched out on the shallower • slopes in such a manner that all compacted fill is in con- tact with the intact bedrock. • • PACIFIC SOILS ENGINEERING, INC. • Work Order 400157AG Page 6 August 24 , 1993 • 4 . All removals, excavations, cleanouts and processing in pre- paring fill areas were observed by this firm' s representa- tive prior to placement of any fill. Based on those obser- vations, all fills are supported by bedrock. • 5. , Compaction tests were taken for each one (1) to two (2) feet of fill placed. The maximum vertical depth of fill placed at this time is on the order of 22 feet along the southerly boundary of the subject project. • 6. The cut portion of this project within structural areas was overexcavated to a minimum depth of 36 inches and replaced with compacted fill. • 7 . The fill slopes were overbuilt approximately three (3) feet during rough grading operations. Upon mass grading comple- tion, the slopes were trimmed back to the compacted core to • achieve design grade. Finish slope surfaces have been probed and/or tested and the slopes are considered to satisfy the project requirements • and grading codes of the City of Temecula. All slopes should be planted as soon as practical and maintained for proper growth. Landscaping and irrigation management are important elements to ensure long term performance of the • slopes. Irrigation should be adjusted seasonally. • • PACIFIC SOILS ENGINEERING, INC. • Work Order 400157AG Page 7 August 24 , 1993 • B. PROPOSED DEVELOPMENT • The subject recreation area (lot 75) is scheduled for con- struction of a pool site, tennis court, basketball court and recreation building, which will be constructed utilizing • wood frame and slab-on-grade construction techniques. C. DESIGN RECOMMENDATIONS • Material encountered in cut and utilized for compacted fill ranged from very low to high in expansion potential. An evaluation of the post-grading soil conditions was conducted to classify materials per ASTM:D 442 and to determine the • expansive index per UBC Standard No. 29-2 . That evaluation revealed low to medium expansive materials exposed at the surface of the building pads. Laboratory test data is pre- sented in Table A. TABLE A • Expansion Expansion Sample Hydrometer Analysis Index Potential Location (%Sand, %Silt, %Clay) (UBC Table 29-C) Tennis Court 66 20 14 N.D. * Low Basketball Court 66 19 15 39 Low • Recreation Center 63 19 18 52 Medium Note: *N.D. - Not Determined. Based upon this data, the following design is presented. • • PACIFIC SOILS ENGINEERING, INC. • Work Order 400157AG Page 8 August 24 , 1993 • 1. Foundations may be designed based upon the following values: • Allowable Bearing: 2000 lbs./sq. ft. Lateral Bearing: 235 lbs./sq. ft. at a depth of 12inches plus 135 lbs./sq. ft. for each additional 12 inches embedment to a maximum of 2000 lbs./sq. ft. • Coefficient of Lateral Sliding: 0. 38 2 . Foundation Recommendations • a) Footing Depth (Minimum) Exterior One-Story - 12 inches below lowest adja- cent finished grade. Two-Story - 18 inches below lowest adja- cent finished grade. Interior • One & Two-Story - 12 inches below lowest adja- cent finished grade. Footing Reinforcement: All continuous; two No. 4 re- bars, one on top, one on bottom. • Slab Reinforcement: Living Areas 61'x 6" ,No. 10 by No. 10 welded wire mesh OR equivalent. Subgrade Moisture: Minimum of optimum moisture plus 5 percent 24 hours prior to concrete place- ment. Continuous footings shall have a minimum width of 12 inches for one-story and 15 inches for two-story. All • slabs shall have a thickness of four (4) inches. If ex- terior footings adjacent to drainage swales are to exist within three (3) feet horizontally of the Swale, the footing should be embedded sufficiently to assure • embedment below Swale bottom is maintained. Footings • PACIFIC SOILS ENGINEERING, INC. • Work Order 400157AG Page 9 August 24 , 1993 • adjacent to slopes should be embedded sufficiently that • at least five (5) feet is provided horizontally from the bottom edge of footings to face of slope. b) Under-Slab Treatment • A 10-mil polyvinyl membrane (minimum) should be placed below all slabs-on-grade within moisture sensitive areas. This membrane should be covered with a minimum of two (2) inches of sand to protect it and to aid in • curing of the concrete and should be underlain with two (2) inches of sand for a capillary rise break. 3 . Retaining Wall Design • Retaining walls or other structural walls shall be designed with the following: a) Cantilevered retaining walls with a level backfill should be designed with an equivalent fluid pressure of • 34 lbs ./cu. ft. Retaining walls with 2-horizontal to 1-vertical slope superjacent to them should utilize an equivalent fluid pressure of 53 lbs./cu. ft. • b) Foundations for retaining walls may be designed in accordance with recommendations of paragraph C-1. C) Retaining walls should be backfilled with free draining • materials (SE > 30) to within 18 inches of grade and compacted to project specifications . Native soils should be utilized in the upper 18 inches. Drainage should be provided to all walls. • PACIFIC SOILS ENGINEERING. INC. • Work Order 400157AG Page 10 August 24 , 1993 • d) All footing excavations for retaining walls should be • observed by the project soil engineer or his repre- sentative. 4 . Exterior Slabs and Walkways • a) It is recommended that the subgrade below sidewalks, driveways, patios, etc. should be moisture conditioned 24 hours prior to concrete placement. • b) Weakened plane joints are recommended for basketball courts , pool decking and walkways at approximately eight (8) to ten (10) foot intervals. Other exterior slabs should be designed to withstand shrinkage of • concrete. C) The "Fibermesh" concrete additive may be considered for exterior concrete work. • 5. Tennis Court It is recommended that a thickened edge should be incorpor- ated into the perimeter of the court and reinforced with two • (2) No. 4 rebars, one (1) on top and one (1) on bottom (mini- mum) . The concrete slab should be a minimum of four (4) inches thick and should be reinforced utilizing a minimum of No. 3 rebars placed on 18 inch centers both ways at mid- height of the slab. The slab should be underlain with a minimum of four (4) inches of clean sand. The subgrade soils should be at or above optimum moisture and compacted to a minimum of 95 percent of the laboratory maximum den- sity. • PACIFIC SOILS ENGINEERING, INC. • Work Order 400157AG Page 11 August 24 , 1993 • 6. Basketball Court • It is recommended that a thickened edge should be incorpor- ated into the perimeter of the basketball court. This thick- ened edge should be reinforced with two (2) No.4 rebars, one (1) on top and one (1) on bottom (minimum) . The concrete • slab should be a minimum of four (4) inches thick and should be reinforced with No. 3 rebars on 18 inch centers, both ways at mid-height of the slab. The slab should be underlain with a minimum of four (4) inches of clean sand. The sub- grade soils should be at or above optimum moisture and com- pacted to a minimum of 95 percent of the laboratory maximum density. • 7 . Pool Decking It is recommended that the pool decking should be a minimum of four (4) inches thick and should be reinforced at mid- height of the slab with six (6) inch by six (6) inch w1. 4 by • w1. 4 welded wire mesh. The pool decking should be underlain with a minimum of four (4) inches of clean sand. The sub- grade soils should be at or above optimum moisture and com- pacted to a minimum of 95 percent of the laboratory maximum • density. D. OTHER DESIGN AND CONSTRUCTION CONSIDERATIONS • 1. Positive drainage away from structures shall be provided and maintained. 2 . Utility trench backfill shall be accomplished in accordance • with the prevailing criteria of the City of Temecula. • PACIFIC SOILS ENGINEERING. INC. • Work Order 400157AG Page 12 August 24 , 1993 • 3 . Seismic design should be based upon current and applicable • building code requirements. 4 . Pavement Design "RII-value testing of a representative sample of the subgrade • soils was conducted. These soils possess an "RII-value of 50. Based upon this IIRII-value of 50, and assumed traffic index (T . I . ) of 5 . 0 the following pavement design is presented: • Pavement design for the parking and driveway areas should incorporate a minimum of three (3) inches of asphaltic concrete over four (4 ) inches aggregate base. The aggregate base and subgrade soils should be • compacted a minimum of 95 percent of the laboratory maximum density. • • • • • PACIFIC SOILS ENGINEERING, INC. • Work Order 400157AG Page 13 August 24 , 1993 • • This report presents information and data relative to the pre- cise grading and placement of compacted fill for the subject site. A representative of this firm conducted periodic tests and observations in an effort to determine whether compliance • with the project drawings, specifications and Building Code were being obtained. The presence of our personnel during the work process did not involve any direction or supervision. Technical advice and suggestions were provided to the owner and/or his representative based upon the results of the tests and observa- tions. Completed work under the purview of this report is con- sidered suitable for the intended use. Conditions of the reference reports remain applicable unless specifically superseded herein. • Respectfully s itted, PACIFIC OILS EN SNEERING, INC. OQ IQ j By: By: Q�_S. zCJgu . • CHANEY, R.C.E. REX P.KETTER,R.C. E. 15251/G.E. 461 4654 , Civil Engi er Chief Executive Officer Regis tion E 6-30-95 A. • 6 By: 0 A. SON, C.E.G.990 � 3y�9> ce President t' a Dist: (6) Addressee CA (1) Costain Homes, Attn: Mr. Adrian Foley (1) Tayco % Taylor-Woodrow Homes, Temecula, Attn: Mr. David Zamiski • JAC/RPK/JAH:kr/AG18 • PACIFIC SOILS ENGINEERING, INC. Work Order 400157AG August 24 , 1993 A P P E N D I X • REFERENCES • 1. Pacific Soils Engineering, Inc. , 1992 , Project Grading Report for Lot 75, Vintage Hills Recreation Center, Tract 22916-1, City of Temecula, CA. , dated January 23 , 1992 (W. 0. 400157AG) . • 2 . Pacific Soils Engineering, Inc . , 1990 , Project Grading Report for Tract 22916-1, Lots 1 thru 74 , incl. , City of Temecula, CA. , dated December 19, 1990 (W. O. 400157AG) . 3 . Pacific Soils Engineering, Inc. , 1988, Geotechnical Grading Plan Review, Tracts 22916, 22916-1, 22916-2 and 22916-3 , • Margarita Village, Rancho California, County of Riverside, CA. , dated December 27, 1988 (W. O. 400158) . • • • • PACIFIC SOILS ENGINEERING, INC. • Work Order 400157AG August 24 , 1992 • TABLE I • SOIL TYPE Laboratory Maximum Density per ASTM:D 1557-78 (All Soil Types) . • Opt. Maximum Moist. Dry Density Soil Type and Classification M (lbs./cu. ft. ) 1 - Tan-Red Sand 9. 1 128 . 4 2 - Tan-Gray Clayey Sand 11. 2 118. 1 • 3 - Dark Brown-Gray Clayey Sand 7 . 5 131. 6 5 - Tan-Gray Clayey Sand 10. 6 122 . 4 6 - Red Silty Sand 8 . 4 130.2 7 - Tan-Gray Silty Sand 9 . 1 127 . 3 • 8 - Tan-Gray Clayey Sand 9 .4 128 . 3 9 - Light Brown Clayey Silt 9 . 8 124 . 5 12 - Tan-Gray Clayey Sand 10 . 2 122 . 5 13 - Tan-Gray. Clayey Sand 10. 9 122 . 5 • 14 - Light Brown Clayey Sand 9 . 7 125. 0 LEGEND Non-Designated Test - Test in compacted fill . • Test Location - Approximate location by street and street stationing; lot number. See enclosed precise grading plans (sheets 1 and 2 of 3) . A - Indicates test number used previously. • B - Indicates test number used previously. TEST TYPE All tests by Campbell Pacific Nuclear Test Gauge per ASTM:D • 2922-1 and D 3017-78 ; unless otherwise noted by: SC - Indicates test taken by Sand Cone Method per ASTM: D 1556-82 . • PACIFIC SOILS ENGINEERING, INC. • Work Order 400157AG August 24 , 1.993 • TABLE I • LOT 75 - RECREATION CENTER Date of Test Test Elev. Moist.Cont. Dry Density Relative Soil Test Test No. Location (ft. ) % (field) (lbs./cu. ft. ) % Comp. Type Type • 11-16-89 803 See Plan 1254 . 0 13 . 1 112 . 6 92 12 804 It 1254 . 0 9 . 1 118. 9 90 3 805 " 1265. 0 8 .7 121. 9 93 3 806 " 1269 . 0 10. 4 116. 3 91 7 Sc • 807 " 1271. 0 10.9 114. 8 90 7 11-17-89 811 See Plan 1254 . 0 7 . 5 118 . 3 91 6 812 11 1263 . 0 11. 2 110. 1 90 12 813 It 1265. 0 13 . 2 114 . 5 92 14 • 814 It 1269. 0 11. 4 116. 5 91 1 Kaiser (Meadows) Parkway 815 Sta. 183+20 1271. 0 11. 0 116. 9 91 1 Sc 816 See Plan 1272 . 0 13 . 1 112 .2 92 12 817 it 1274 . 0 8. 8 117 . 7 92 1 818 it 1273 . 0 7 . 5 114 . 2 93 12 • 819 It 1273 . 0 7 . 3 113 . 1 92 12 820 It 1256. 0 7 . 8 111. 2 91 12 11-20-91 824 See Plan 1256. 0 11. 6 118 . 8 93 1 It 825 It 1264 . 0 10. 1 122 . 6 95 1 • 826 It 1270. 0 12 . 9 117 . 4 91 1 827 It 1273 . 0 9 . 1 120. 9 94 1 828 It 1273 . 0 8 .7 120. 4 94 1 829 If 1258 . 0 11.4 119 . 0 93 1 Sc 12-7-89 • 985 See Plan 1262 . 0 8.7 114 .7 92 9 12-8-89 1006 See Plan 1265. 0 11. 6 111.9 91 12 12-11-89 • 1038 See Plan 1273 . 0 12 . 1 109 . 6 93 2 1040 it 1267 . 0 11. 1 114 . 5 94 12 1042 of 1276. 0 9. 8 111. 4 91 12 • PACIFIC SOILS ENGINEERING, INC. • Work Order 400157AG August 24 , 1992 TABLE I cont. LOT 75 - RECREATION CENTER Date of Test Test Elev. Moist.Cont. Dry Density Relative Soil Test • Test No. Location (ft. ) % (field) (lbs./cu. ft. ) % Comp. Type Type 12-11-89 cont. 1043 See Plan 1272 . 0 10.2 112 . 7 92 12 1045 " 1278. 0 10.8 117 . 6 92 8 1046 " 1276. 0 10.7 107 . 1 91 2 12-18-89 1152 See Plan 1260. 0 11. 6 115. 2 93 9 1153 " 1267. 0 13 . 1 115 .7 93 9 1154 " 1270. 0 12 . 5 112 . 2 92 5 12-21-89 1232 See Plan 1270. 0 11. 0 112 . 5 92 12 1-8-91 859A See Plan 1283 . 0 9. 0 110. 6 90 13 860A 11 1283 . 0 8 . 6 114 . 2 93 13 861A it 1283 . 0 7 . 9 116. 4 95 13 1-11-91 887A See Plan 1285. 0 11. 6 114 .7 92 14 888A It 1285. 0 12 . 1 116. 1 93 14 889A " 1285. 0 10. 9 115. 3 92 14 1-15-91 Kaiser (Meadows) Parkway 906A Sta. 179+60 1271. 0 10.7 116. 1 95 13 907A Sta. 179+60 1274 . 0 11.9 114 . 3 93 13 908A Sta. 179+60 1278. 0 10.9 113 .9 93 13 6-10-93 104B Pool Area 1283 . 0 10. 3 114 . 2 91 14 105B Pool Area 1285. 0 9.9 115. 1 92 14 106B Pool Area 1284 . 0 11.2 112 .7 90 14 107B Tennis Ct. 1281. 0 10.9 111. 8 91 13 108B Tennis Ct. 1282 . 0 11.7 115. 9 93 14 109B Tennis Ct. 1281. 0 9. 8 112 . 9 90 14 110B Tennis Ct. 1282. 0 10. 4 113 . 1 92 13 PACIFIC SOILS ENGINEERING, INC.