Local Calibration of “C-Values” for Common Idaho Soil Types for Use in Mechanistic-Empirical Pavement Design

Details

• Creators:
  Santi, Michael J ; Crawforth, Stanly G ; Tamim, Mir ; Kassem, Emad
• Corporate Creators:
  Shannon & Wilson, Inc.
• Corporate Contributors:
  Idaho. Transportation Department. Research Program ; United States. Department of Transportation. Federal Highway Administration
• Subject/TRT Terms:
  AASHTOWare Pavement ME Design EFWD Falling Weight Deflectometers Geotechnical Engineering Mechanistic-empirical Pavement Design Modulus Of Resilience Pavement Design Soil Types C-Value
• Publication/ Report Number:
  RP 289
• Resource Type:
  Tech Report
• Geographical Coverage:
  Idaho;United States
• Edition:
  Final Report 05/01/2019 - 05/31/2022
• Corporate Publisher:
  Idaho Transportation Department
• Abstract:
  AASHTOWare Pavement ME software has been adopted by the Idaho Transportation Department (ITD) for Mechanic-Empirical analysis of pavement structures. AASHTOWare analyses are platformed on the laboratory resilient modulus test, AASHTO T 307. The test is appropriate for evaluating “undisturbed” subgrade samples and reconstituted materials. Laboratory tests are conducted to measure the response of materials under conditions simulating moving wheel loads. Falling Weight Deflectometer (FWD) tests also provide field measurements of pavement deflection or response under conditions simulating moving wheel loads. To correlate laboratory-established resilient moduli with moduli back-calculated from field tests, AASHTOWare utilizes a ratio called the “C-Value,” or MR/EFWD Ratio. Global default values have been developed that may be overly conservative for Idaho roadways, resulting in thicker pavements The objective of this study was to develop a database of laboratory resilient moduli together with appurtenant FWD data, such that local Idaho C-Values could be determined. This study used design-funded projects to collect C-Value data during the duration of the research project and leverage it into a state-wide calibration of the important and analysis-sensitive C-Value. The results of this work suggest that the Level 3 global default values are conservative and should be replaced by local Level 2 values and ITD would benefit from routinely conducting MR testing on most projects. An Excel Spreadsheet contains materials properties for soils encountered and calculated C-Values. The spreadsheet is designed to be updated as new data are collected. Global default values have been developed that may be overly conservative.
• Format:
  PDF
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha-512:a7d3e7a93f5fee91acb4f7cbd8826ba1eafe9ca1c9911aa58f63b2123b079078006f7edecb0dc67795ecb7cebe98da9f6b252ee5824c7c06eae1a95c4953b54c
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/63531/dot_63531_DS1.pdf
• File Type:
  [PDF - 2.24 MB ]