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HomeMy WebLinkAboutCT 05-13; LA COSTA RIDGE NEIGH 2.6; LAB TEST DATA AND PAVEMENT DESIGN SECTIONS; 2009-09-25PACIFIC SOILS ENGINEERING, INC. 7715 CONVOY COURT, SAN DIEGO. CALIFORNIA 92111 TELEPHONE: (858) 580-1713, FAX: (858) 560-0380 D.R. HORTON INC. 1021 Costa Pacifica Way 42107 Oceanside, CA 92054 September 25, 2009 Work Order 401036G Attention: Ms. Kim Molina Subject: Laboratory Test Data and Pavement Design Sections for the La Costa Ridge Project, Neighborhood 2.6, in the City of Carlsbad, California. Dear Ms, Molina: Presented herein are Pacific Soils Engineering, Inc.'s (PSE) laboratory test data results and pavement design recommendations for the La Costa Ridge Project, Neighborhood 2.6, in the City of Carlsbad, California. Soil samples for resistance ('R") value testing were taken on Filoli Circle at the direction of City of Carlsbad personnel. The "R"-value test results with their respective locations are presented in Table I. The "R"-values of the sampled material were determined in accordance with California Test Method 301. A traffic index of 5.0 was provided by the City of Carlsbad for Filoli Circle. Based on the "R"-value test results and the traffic index, the recommended pavement section for Filoli Circle is four (4) inches of asphalt concrete over five (5) inches of aggregate base. Pavement design calculations are presented on Plate A. Four inches of asphalt concrete is the City of Carlsbad minimum. CORPORATE HEADQUARTERS LOS ANGELES COUNTY RIVERSIDE COUNTY SOUTH ORANGE COUNTY TEL: (T14) 220-0770 TEL: (3101325-7272 01(323)775-6171 TEL: (061) 582-0170 TEL: (714) 730-2122 FAX: (714) 220.9569 FAX: (714)'220-9589 FAX: (951) 582-0176 FAX: (714) 730-5191 [1 Work Order 401036G Page 2 September 25, 2009 TABLE I SUMMARY OF LABORATORY DATA SAMPLE LOCATION SAMPLE RESISTANCE VALUE (R-Value) R-1 Filoli Circle Ste. 2+00 32 R-2 Filo]i Circle Ste. 5+00 22 R-3 Filoli Circle Sta. 7+75 24 R-4 Hioli Circle Sta. 9+60 20 R-5 Fi!oli Circle Sta. 11+75 29 R-6 FilcH Circle Ste, 13+90 26 As part of preparation for placement of aggregate base (AB) material and asphaltic concrete (AC), the subgrade should be suitably moisture conditioned, processed and compacted as necessary to attain near optimum moisture content and a minimum 95 percent of the laboratory maximum density (ASTM;D 1557-02) to at least eight (8) to twelve (12) inches below the subgrade. After subgrade compaction, the exposed grade should be "proof"-rolled with heavy equipment to verify the grade does not "pump" and is observed to be non-yielding. The aggregate base (AB) material should be compacted to a minimum of 95% of the laboratory maximum density (California Test Method 216E, modified). Preparation of subgrade, base and pavement should be accomplished in accordance with the current requirements of the City of Carlsbad and under the observation and testing of the project soil engineer. This report is under the purview of the City of Carlsbad. PACIFIC SOILS ENGINEERING, INC. Work Order 4010360 Page 3 September 25, 2009 If there are any questions or we may be further assistance, please contact our San Diego office. Respectfully submitted, PACIFIC SOILS ENGINEERING, INC. By: Manager of Geotechnical Services Dist: (1) Addressee PACIFIC SDILS ENGINEERING,INC. STRUCTURAL PAVEMENT CALCULATIONS Filoli Circle, La Costa Ridge City of Carlsbad, California SUBCRADE SOILS R-VALUE, R 20 TRAFFIC INDEX, TI - 5.0 GRAVEL EQUIVALENT (TOTAL) =0.0032(TI)(l0O-R) GE(TOTAL) 0.0032 ( 5-0)(100-20) = 15.36 INCHES DESIGN A.C. THICKNESS AGGREGATE BASE R-VALIJE = 78 (CLASS U OR EQUIVALENT) GE(AC)* =( 0.0032 (5.0)(100-78))+0.2 = 6.60 INCHES 9iictudes 0.2 fcei oddd to OE(AC) as a safeLy lactor for determining the minimum AC thickness per Caltrans Highway Design Manual J. Gf(AC) = 2.5(5. 14/TI)"0.5 = 2.5(5. 14/5,00.5= 2.535 Round to 2.50 MIMIMUM AC THICKNESS 4.00 INCHES AC LAYER = 6.60/2.50 2.64 INCHES USE 4.00 INCHES DESIGN BASE THICKNESS SUBGRADE R-VALUE = 20 GE(AB) = GE(TOTAL) - GE(AC) GE(AB) = 15.36- 10.00 = 5.36 INCHES GRAB) = 1.10 MIMI MUM AB THICKNESS 4.00 INCHES BASE LAYER= 5.36/1.I =4.87 INCHES USE 5.00 INCHES Recommended Section 4.00 inch AC on 5.00 inch AB PLATE A PACIFIC SOILS ENGINEERING, INC.