Poster 20-14

Guidelines for Incorporation of Cement Stabilized Reclaimed Base (CSRB) in Pavement Design

PI: Jayhyun Kwon

Co-PI(s): Youngguk Seo

Institution(s): Kennesaw State University

Abstract

GDOT is in the process of implementing an updated Mechanistic-Empirical Pavement Design Guide (MEPDG). To support this implementation, a research study was conducted to calibrate the national performance models for local conditions. However, reliable calibration coefficients could not be derived for semi-rigid pavements due to the lack of sufficient performance data. GDOT will therefore continue to utilize the current pavement design procedure (AASHTO 72/93) until appropriate MEPDG local calibration coefficients have been identified. This research project was undertaken to improve the reliability of the current GDOT pavement design procedure for CSRB and to provide recommendations regarding the steps required to verify and calibrate CSRB for use in MEPDG. A preliminary laboratory study of typical CSRB mix and field cores was conducted to characterize the CSRB materials and evaluate the accuracy of the relationship between elastic modulus and unconfined compressive strength, after which performance data was collected for samples from 4 different sites in Georgia. The FWD deflection data and UCS values of the field cores were then used to calculate the structural layer coefficient of the CSRB layer and a sensitivity analysis was performed to identify the input variables with the greatest influence on the performance predicted by the PMED. Two different pavement types were used to model the FDR pavement: flexible pavement and semi-rigid pavement. Finally, a data collection plan was developed to guide the collection of the data needed for local calibrations of the MEPDG for roads in Georgia.

Please comment below with any statements or questions you may have. Also let GTI if you would be interested webinars or presentations on similar topics.