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Home My WebLink AboutCT 00-06; BRESSI RANCH; FLEXIBLE PAVEMENT RECOMMENDATIONS; 2006-03-206r 00 - op Geotechnical Engineering Construction Inspection Materials Testing Environmental Office Locations Orange County Corporate Branch: 2992 E. La Palma Avenue Suite A Anaheim, CA 92806 Tel: 714.632.2999 Fax: 714.632.2974 March 20, 2006 Mr. Clint Fowler Lusardi Construction Co. 1570 Linda Vista Drive San Marcos, CA 92078 Subject: Flexible Pavement Recommendations With Lime Treated Subgrade Project No. 1446-A03 Log No. 06-368 San Diego Imperial County 7313 Carroll Road Suite G San Diego, CA 92121 Tel: 858.537.3999 Fax: 858.537.3990 Central Dispatch 800.491.2990 www.mtglinc.com Project: Loker Business Center NWC Palomar Airport Road & Loker Avenue West Carlsbad, CA Permit No. CB052695 Dear Mr. Fowler: We understand that the prepared subgrade under pavement is currently yielding or unstable as a result of the recent rain. Due to the yielding subgrade, it is planned to treat the current subgade soil with lime. In conjunction with this and as you requested, we have obtained a representative soil samples on the current subgrade soil under proposed pavement for R- value testing mixed with lime. Laboratory Testing Two soil samples were prepared mixed with 6 percent and 7 percent lime by weight and the R-value testing was performed in general accordance with Caltrans Test Method 301. The R-value results are summarized below. Sample No. R-Value With 6%lime 61 With 7 % lime 78 A higher R-value result was obtained for the soil mixed with lime compared to an untreated soil that was previously tested resulting to a R-value of between 11 and 15 (MTGL, Inc. report dated February 8, 2006). Our analysis presented in this report utilized a R-value of 61 (with 6 percent lime by weight). Los Angeles Ventura County 13010 San Fernando Road Unit 1 Sylmar, CA 91342 Tel: 818.833.8100 Fax: 818.833.0085 Inland Empire 14320 Elsworth Street Suite C1O1 Moreno Valley, CA 92553 Tel: 951.653.4999 Fax: 951.653.4666 Loker Business Center Project No. I446-A03 Carlsbad, CA Log No. 06-368 Pavement Structural Section Our engineering analysis included a Traffic Indexex of 4.5, 6.0 and 7.0 for auto parking stalls, auto driveways and fire lane/heavy trucks, respectively; which are consistent with the recommendations of Geocon Inc. that were presented on their geotechnical report dated December 17, 2003. Based upon our engineering analysis following the standard design procedures for flexible pavement as outlined in Caltrans Highway Design Manual, the required pavement sections are as follows: Traffic Index R-Value w/ 6 Percent Asphalt Concrete Aggregate Base Lime 4.5 Auto Parking 61 3.0 or 4.0 inches 0.0 inches * Stall 6.0 Auto Driveway 61 3.0 inches 2.0 inches * or or 4.0 inches 0.0 inches * 7.0 Fire Lane/Heavy 61 4.0 inches 2.0 inches * Trucks NOTE: * Do not conform with the minimum per Supplemental Standard No. GS-17 by the City of Carlsbad. As such, the minimum structural section to be implemented to conform with the Supplemental Standard No. GS-17 shall be as follows: Traffic Index R-Value w/ 6 Percent Asphalt Concrete Aggregate Base Lime 4.5 Auto Parking 61 4.0 inches 4.0 inches Stall 6.0 Auto Driveway 61 4.0 inches 6.0 inches 7.0 Fire Lane/Heavy 61 4.0 inches 6.0 inches Trucks Lime Treatment The extent of the lime treated subgrade should be at least 12 inches deep, but not to exceed 15 inches. Based upon the results of the R-value testing, we recommend at least a mixture of 6 percent lime by weight. Preparation of subgrade, spreading and mixing lime, spreading and compacting, and curing shall be in accordance with the Greenbook, Standard 2 Loker Business Center Project No. 1446-A03 Carlsbad, CA Log No. 06-368 Specifications for Public Works Construction (SSPWC) Section 301-5, 2006 Edition. A specialty contractor with appropriate equipment is anticipated to perform the work. Lime treated subgrade soil shall be compacted to at least 95 percent relative compaction based on Test Method ASTM D1557. Aggregate Base Material Base material under pavement areas shall conform to the requirements of Caltrans Section 26 or Section 200-2 of the SSPWC. Base material shall be spread and compacted in layer not to exceed 6 inches thick. Aggregate base shall be moisture conditioned to near optimum moisture content during placement. The relative compaction of each layer of compacted base material shall not be less than 95 percent per Test Method ASTM Dl 557. Compaction testing shall be performed to verify compliance. Asphalt Concrete Asphalt concrete shall be dense, hot-laid, hot mix asphalt plant mixes with a history of satisfactory performance in geographical area where project is located and approved by authorities having jurisdiction. Hot-mix asphalt paving materials, workmanship and other requirements shall be in accordance with Section 203-6 of the SSPWC. Geotechnical ObservationlTesting The geotechnical consultant shall perform geotechnical observation and testing to ascertain that conditions corresponds to the findings and conclusions and that construction conform generally to the recommendations presented herein. If you have any questions regarding our report, please do not hesitate to contact this office. We appreciate this opportunity to be of service. Respectfully submitted, MTGL, Inc. Eduardo C. Dizon, RCE Project Engineer RCE 57217, Exp. 12/31/07 cc: Mr. Casey R. Arndt / City of Carlsbad Attachment: R-Value Lab Result 3 R-VALUE TEST REPORT 100 80 - ------------- 60 a) - Of 40 20 LU_L JJJJ JJJJ LLLL JJJI 0 .LLLL JJJJ. JJJJ JJJJ. 1.L.LL LLLL LLLL JJJJ. JJJJ. 800 700 600 500 400 300 200 100 Exudation Pressure - psi Resistance R-Value and Expansion Pressure - Cal Test 301 No. Compact. Pressure psi Density pcf Moist. % Expansion Pressure psi Horizontal Press. psi @ 160 psi Sample Height in. Exud. Pressure psi R Value R Value Corr. 240 96.3 25.8 0.18 85 2.57 102 34 35 2 350 100.7 23.8 0.39 64 2.64 204 47 50 3 350 102.8 20.1 1.18 22 2.40 715 82 80 Test Results Material Description R-value at 300 psi exudation pressure = 61 CLAY (CL), yellowish tan with 6% lime added Project No.: 1446-A03 Project:Loker Business Park Location: Main parking tot Date: 3/19/2006 Tested by: SF1 Checked by: ED Remarks: Lab #0147 Figure R-VALUE TEST REPORT MTGL, Inc. RESISTANCE R-VALUE TESTING RESULTS (Cal Test 301) Date: Project No.: Project: Location: Material Description: Tested by: Checked by: Remarks: 3/19/2006 1446-A03 Loker Business Park Main parking lot CLAY (CL), yellowish tan with 6% lime added JH ED Lab #0147 Compaction pressure (psi): Wet weight (gins): Dry weight (gins): Tare weight (gins): 240 1341.1 1066.2 0.0 350 1320.0 1066.2 0.0 350 1280.0 1066.2 0.0 Moisture: 25.8 23.8 20.1 Exudation load (lbs.) : 1280 2560 8980 Exudation pressure (psi): 102 204 715 Total weight (gins.): Mold weight (gins.): 3048.0 2021.0 3111.0 2025.0 3003.0 2026.0 aznplewéight (gins.): 1027.0 1086.0 977.0 Initial expansion (x10,000) : Final expansion (xlO,000) : 0 6 0 13 0 39 Ixpansion pressure (psi): 0.18 0.39 1.18 Ph at 2000 lbs.: D turns: 85 4.36 64 4.30 22 3.52 34 47 82 Height (in.): 2.57 2.64 2.40 )ry density (pcf) : 96.3 100.7 102.8 orrectedR: 35 50 80 R-Value at 300 psi exudation pressure = 61 MTGL, Inc. R-VALUE TEST REPORT 100 - - - 80 - 60 a) - 40 20 0 :LLJ_L LLLL LLII ILLL .JJJJ. ..LLLL 1JJJ .LLII LLLJ. JJJJ LIJJ LLLL JJJJ. ±.L.LL 800 700 600 500 400 300 200 100 Exudation Pressure - psi Resistance R-Value and Expansion Pressure - Cal Test 301 No. Compact. Pressure psi Density pcf Moist. % Expansion Pressure psi Horizontal Press. psi @ 160 psi Sample Height in. Exud. Pressure psi R Value R Value Corr. 350 92.4 18.8 1.42 19 2.40 715 86 85 2 350 105.5 20.6 0.52 21 2.45 379 83 83 3 350 104.6 21.5 0.82 39 2.66 250 70 73 Test Results Material Description R-value at 300 psi exudation pressure = 78 CLAY (CL), grayish green with 7% lime added Project No.: 1446-A03 Project:Loker Business Park Location: North west parking lot Date: 3/19/2006 Tested by: JH Checked by: ED Remarks: Lab #0148 Figure R-VALUE TEST REPORT MTGL, Inc. RESISTANCE R-VALUE TESTING RESULTS (Cal Test 301) Date: Project No.: Project: Location: Material Description: Tested by: Checked by: Remarks: 3/19/2006 144 6-A03 Loker Business Park North west parking 1t CLAY (CL), grayish green with JH ED Lab #0148 7% lime added Compaction pressure (psi) : Wet weight (gins): Dry weight (gins): Tare weight (gins): 350 1300.0 1094.3 0.0 350 1320.0 1094.3 0.0 350 1330.0 1094.3 0.0 Moisture: 18.8 20.6 21.5 Exudation load (lbs.): 8980 4760 3146 Exudation pressure (psi): 715 379 250 Total weight (gins.): Mold weight (gins.): 2891.0 2022.0 3045.1 2017.0 3146.0 2030.0 ampleweig1it (gins.): 869.0 1028.1 1116.0 7 Initial expansion (xlO,000) : Final expansion (xlO,000) : 0 47 0 17 0 27 Expansion pressure (psi): 1.42 0.52 0.82 Ph at 2000 lbs.: D turns: 19 3.09 21 3.31 39 3.30 86 83 70 Height (in.): 2.40 2.45 2.66 ry density (pcf): 92.4 105.5 104.6 orrectedR: 85 83 73 R-Value at 300 psi exudation pressure = 78 MTGL, Inc.