The URL can be used to link to this page

Home My WebLink About3676; PALOMAR AIRPORT RD AND EL CAMINO REAL TURN LANES; R-VALUE TESTING AND PAVEMENT SECTION DESIGNS; 1999-11-10MOM AL Leighton and Associates Room AGTGCompany GEOTECHNICAL CONSULTANTS November 10, 1999 Project No. 4990220-001 To: Berryman & Henigar 11590 West Bernardo Court, Suite 100 San Diego, CA 92127-1624 Attention: Mr. Mark Risch Subject: R-Value Testing and Pavement Section Design, Proposed Shoulder Widening at the Intersection of El Camino Real and Palomar Airport Road, Carlsbad, California References: P & D Technologies, 1992, Plans for Signing and Striping of P.A.R. 99+22.38 to 109+00.00, E.C.R 314+75 to 320+91.07, Carlsbad, California, Sheet 89 of 135, Project No. 3341, dated July 6, 1992 In accordance with your request, we have performed limited geotechnical sampling, testing and analysis to develop design pavements sections for the proposed shoulder widening project at the intersection of El Camino Real and Palomar Airport Road in Carlsbad, California. We understand the project will consist ' ,of widening approximately 500 lineal feet of the northbound and westbound shoulders of El Camino Real and Palomar Airport Road. To develop design parameters for analysis of pavement sections, a representative from our firm collected samples from two pothole excavations excavated along the proposed shoulder alignments. Each of the collected samples was tested for resistance value (R-Value) in accordance with Cal Test Method 301. The results of our laboratory analysis are presented in Table 1 below. Table 1 Summary of Laboratory Test Results Sample Location Sample Description R-Value El Camino Real Brown, silty CLAY with fine gravel 27 STA 318+15 Palomar Airport Road Brown, silty CLAY with fine gravel 29 STA 101+70 3934 Murphy Canyon Road, #B205, San Diego, CA 9213-4425 (619) 292-8030 • FAX (619) 292-0771 0 www.leightongeo.com 990220-001 As requested, design pavement sections were determined using a design traffic index (T.I.) of 9. The design pavement sections were calculated using the methodology outlined in the Caltrans Highway Design Manual. Minimum thicknesses were determined according to the Standards for Design and Construction of Public Works Improvements in the City of Carlsbad (SDCPWI). Pavement sections are provided for various base and subbase combinations and for hill-depth asphalt concrete. It is noted that the full-depth design according to Caltans methodology does not incorporate the minimum aggregate base thickness specified in the SDCPWI. Summaries of the pavement section design calculations utilizing Caltrans design methods are attached. The design sections are based on the lower of the two subgrade R-Value results. Additional R-Value testing should be performed during grading on representative soils exposed at the subgrade elevation. If the subgrade materials exposed during grading possess a lower R-Value, increased section thickness will be required. Asphalt Concrete and Crushed Aggregate Base Section The sections provided in Table 2 are for pavements constructed using asphalt concrete (AC) over crushed aggregate base. To allow for specification of a uniform section utilizing a thinner section of crushed aggregate base, calculations were performed for the condition where the pavement section is underlain by a subbase that possesses an R-Value of at least 50. Also reported is the condition combining the minimum aggregate base thickness (per City of Carlsbad SDCPWI requirements) and a thicker AC section. Table 2 Asphalt Concrete and Aggregate Base Pavement Section AC over Crushed AC over Crushed Aggregate Base Aggregate Base over Subbase Crushed Crushed Traffic Index (T I) Design R-Value Asphalt Concrete Thickness Aggregate Base Thickness Asphalt Concrete Thickness Aggregate Base Thickness - 50 R =50 Subbase Thickness (inches) (inches) (inches) (inches) (inches) 9.0 27 6 13 6 6 8 9.0 27 10 6 6 6 8 All aggregate base, subbase, and the upper 12 inches of subgrade should be compacted to a minimum 95 percent relative compaction based on American Standard of Testing and Materials (ASTM) Test Method D1557. Compacted materials should be placed at near optimum moisture content. Crushed aggregate base and Asphalt Concrete should conform to and be placed in accordance with the "Greenbook" Standard Specifications for Public Works Construction (Sections 200, 203, and 400) and the City of Carlsbad requirements. 990220-001 Full-Depth Asphalt Concrete Section The sections provided in Table 3 are for pavements constructed using full-depth asphalt concrete. Table 3 Full-Depth Asphalt Concrete Pavement Section Traffic Index (T.I.) Design R-Value Asphalt Concrete Thickness (inches) 9.0 27 :E 14.0 The upper 12 inches of subgrade should be compacted to a minimum 95 percent relative compaction based on American Standard of Testing and Materials (ASTM) Test Method D1557. Compacted materials should be placed at near optimum moisture content. Asphalt concrete should conform to and be placed in accordance with the "Greenbook" Standard Specifications for Public Works Construction and the City of Carlsbad requirements. If you have any questions regarding our report, please contact this office. We appreciate this opportunity to be of service. Respectfully submitted, LEI HTON AND TES, INC. Sea do, RCE #540 Senior Project Engineer Attachments: Asphalt Pavement Section Design Calculations Distribution: (3) Addressee ASPHALT PAVEMENT SECTION DESIGN CALCULATION FOR ASPHALT CONCRETE AND CRUSHED AGGREGATE BASE SECTION Minimum AC Minimum Base DESIGN INPUT Section Section 990220-001 TRAFFIC INDEX SUBGRADE R-VALUE CRUSHED AGG BASE R-VALUE 9 9 27 27 80 80 STRUCTURAL CALCULATIONS REQUIRED GETOTAL AC GRAVEL FACTOR GEnc GEAC+ SF THICKNESSnc DESIGN THICKNESSAC GEDESIGNAC 2.102 2.102 1.89 1.89 0.576 0.576 0.776 0.776 4.927 4.927 6.0 10.0 0.945 1.575 GEBASE BASE GRAVEL FACTOR THICKNESSBAsE DESIGN THICKNESSBASE DESIGN SECTIONS AC CRUSHED AGGREGATE BASE 1.157 0.527 1.1 1.1 12.626 5.753 13.0 6.0 6.0 in JO.0in 13.0 in 6.0 in II ASPHALT PAVEMENT SECTION DESIGN CALCULATION FOR ASPHALT CONCRETE, CRUSHED AGGREGATE BASE, AND AGGREGATE SUBBASE SECTION DESIGN INPUT TRAFFIC INDEX 9 SUBGRADE R-VALUE 27 SUBBASE R-VALUE 50 CRUSHED AGG BASE R-VALUE 80 STRUCTURAL CALCULATIONS REQUIRED GETOTAL 2.102 AC GRAVEL FACTOR 1.89 GEAC 0.576 GEAC+ SF 0.776 THICKNESSAc 4.927 DESIGN THICKNESSAC 6.0 GEDESIGNAC 0.945 REQUIRED GEAC+ BASE 1.440 GEBASE 0.495 BASE GRAVEL FACTOR 1.1 THICKNESSBAsE 5.400 DESIGN THICKNESSBASE 6.0 GEDESIGNBASE 0.550 GEDESIGNAC+BASE 1.495 GESUBBASE 0.607 THICKNESSSUBBASE 7.289 DESIGN THICKNESSSUBBASE 8.0 DESIGN SECTIONS AC CRUSHED AGGREGATE BASE SUBBASE 990220-001 ASPHALT PAVEMENT SECTION DESIGN CALCULATION FOR FULL-DEPTH ASPHALT CONCRETE DESIGN INPUT TRAFFIC INDEX 1 9 ::::] SUBGRADE R-VALUE 1 27 STRUCTURAL CALCULATIONS AC GRAVEL FACTOR 1.89 GEAC 2.102 GEAC+ SF 2.202 THICKNESSAC 13.983 DESIGN THICKNESSAC 14.0 GEDESIGNAC 2.205 DESIGN SECTIONS AC 140in 990220-00)