Pavement Design ensures that highway pavements are properly designed by providing the oversight, expertise and design tools required for pavement design. All Pavement Design Requirements are included in the. Pavement Design Oversight Most pavement designs produced by WSDOT originate in one of the six Regions. HQ Pavement Design ensures that the Region's pavement designs comply with, are cost effective and constructible.

MODTAG Combination of TAG and MODCOMP TAG -Test and Guess. Backcalculation of Unbound Granular Layer Moduli. MODTAG is a backcalculation software developed.

Specialized Designs HQ Pavement Design supports the Regions by preparing specialized or complex pavement designs. Pavement Type Selection HQ Pavement Design provides technical assistance and oversight of the pavement type selection process (asphalt versus concrete) and other pavement investment decisions. Falling Weight Deflectometer The Falling Weight Deflectometer (FWD) is a non-destructive testing device used to complete structural testing for pavement rehabilitation projects, research, and pavement structure failure detection.

HQ Pavement Design provides FWD testing services throughout the state. Superload Analysis HQ Pavement Design provides assistance to WSDOT's by analyzing the impact of superloads over 300,000 pounds to highway pavement structures.

Notice This document is disseminated under the sponsorship of the U.S. Department of Transportation in the interest of information exchange. Government assumes no liability for the use of the information contained in this document. Government does not endorse products or manufacturers. Trademarks or manufacturers' names appear in this report only because they are considered essential to the objective of the document. Quality Assurance Statement The Federal Highway Administration (FHWA) provides high-quality information to serve Government, industry, and the public in a manner that promotes public understanding.

Standards and policies are used to ensure and maximize the quality, objectivity, utility, and integrity of its information. FHWA periodically reviews quality issues and adjusts its programs and processes to ensure continuous quality improvement.

Technical Report Documentation Page 1. FHWA-HRT-15-036 2. Government Accession No. 3 Recipient's Catalog No.

Title and Subtitle Long-Term Pavement Performance Program Determination of In-Place Elastic Layer Modulus: Backcalculation Methodology and Procedures 5. Report Date December 2015 6. Performing Organization Code 7. Author(s) Harold L. Von Quintus, P.E., Chetana Rao, and Lynne Irwin 8.

Performing Organization Report No. Performing Organization Name and Address Applied Research Associates, Inc.

100 Trade Centre Drive, Suite #200 Champaign, IL 61820 10. Work Unit No. Contract or Grant No. DTFH61-11-C-00051 12. Bell Bike Trailer Stroller Manual here. Sponsoring Agency Name and Address Office of Infrastructure Research and Development Federal Highway Administration 6300 Georgetown Pike McLean, VA 13.

Type of Report and Period Covered Draft Final Report September 30, 2011–October 30, 2014 14. Sponsoring Agency Code 15. Supplementary Notes The Contracting Officer’s Technical Representative (COTR) was Ms. Yan 'Jane' Jiang. Abstract Deflection data have been measured at periodic intervals with a falling weight deflectometer on all rigid, flexible, semirigid, and rehabilitated pavement test sections included in the Long-Term Pavement Performance (LTPP) program.

A common use of deflection data is to backcalculate in-place layered elastic modulus values. The Federal Highway Administration sponsored earlier studies to backcalculate elastic layer modulus values from deflection basins measured on all LTPP test sections and included those computed values in the LTPP database.

(3–5) While the earlier studies focus on the use of nonlinear methods and were considered to have minimal success, Some of the methods used have advanced within the past decade. As such, there was a need to revisit the methods used to improve on the results. This report summarizes all activities completed to backcalculate the elastic layered modulus from deflection basins measured on all test sections included in the LTPP program. Specifically, the report documents the tools, data analyses, backcalculation and forward calculation packages, and procedures used to calculate, on a production basis, the in-place elastic layer modulus of the LTPP test sections.

Multiple packages (including BAKFAA, EVERCALC ©, MICHBACK ©, MODULUS, MODCOMP ©, and the area and best fit methods) were considered and evaluated for estimating layered elastic modulus values on a production basis. (See references 6–10.) The methods used in production for backcalculating elastic layer moduli include a combination of EVERCALC © and MODCOMP © for all types of pavements and the best fit method for rigid pavements.