Modelling permanent strain behaviour of soil for flexible pavement design utilizing LWD measurements

Abstract

ABSTRACT This study aims to improve understanding of unbound material behavior by modeling permanent strain using Light Weight Deflectometer (LWD) measurements, as part of VTI’s broader LWD research. By comparing permanent strain modelling from LWD data with Repeated Load Triaxial (RLT) tests on silty sand soils, it validates LWD data accuracy and explores material property influences on permanent strain parameters, revealing a clear correlation with water content and stress levels. Using LWD data validated against RLT tests, the study delves into material behaviour understanding under varied conditions, focusing on comparing model parameters of permanent strain prediction derived from LWD and RLT tests. Despite minor differences, both methods produce acceptable values, affirming the modelling approach’s robustness. The findings demonstrate LWD’s potential to improve pavement design by providing insights into permanent strain behavior that supports mechanistic-empirical approaches, leading to more efficient designs and better resource use for improved performance.