ABSTRACT
To locally calibrate the Mechanistic-Empirical Pavement Design Guide (MEPDG) for the state of Wyoming, a comprehensive test programme and analyses were conducted. The field test programme included falling weight deflectometer tests, standard penetration tests, dynamic cone penetration tests and soil sampling. These field tests were conducted at 12 locations or 36 sites in the state of Wyoming. Subgrade soils collected from the field were characterised by a series of laboratory soil tests including resilient modulus tests, resistance-value tests and standard Proctor density tests. This test programme accumulated significant valuable soil data for local MEPDG calibrations. To efficiently store the results from the field and laboratory testing, an electronic WYOming MEPDG Database was developed using Microsoft® Access. Specific data or inputs requested by user are efficiently and easily sorted, filtered and queried using the database. Laboratory measured resilient modulus, resistance-values and standard Proctor properties of subgrade materials were used to develop both multivariate and univariate multi-regression models to accurately estimate resilient modulus for MEPDG Level 2 design inputs. Statistical parameters were used to effectively evaluate the performance of developed regression models. The resistance-value and optimum moisture content of subgrade soils were determined as important predictors in both models. The research outcomes facilitate the local calibration and implementation of the MEPDG.
Acknowledgements
The authors would like to thank the Wyoming Department of Transportation for sponsoring the research presented in this paper. We would like to thank the WYDOT engineers from the Geology and Materials Programs as well as the WYDOT field crews for their assistance in the field and laboratory test programme. Special thanks are due to Denial Hellrung and Zachary Henrichs for their valuable input.