Measurement and Finite Element Modeling of the Pavement Response to Superloads

The goal of this study is to examine the feasibility of using a bridge structural testing system and finite element modeling (FEM) to assess the impact of heavy hauls in terms of stresses and the corresponding reduction in service life for portland cement concrete (PCC) pavements on grade. FEM simulation results are compared for various numerical treatments of the subgrade using the programs EverFE and COMSOL. With the simplified dense liquid foundation subgrade treatment used in EverFE, the experimentally measured bending strain profile in the slab could not be accurately captured using a single coefficient of subgrade reaction. A more general optimized 3D solid subgrade model was developed in COMSOL using the pseudo-coupled method, by modeling a large solid soil domain surrounding the slab, with the subgrade modulus increasing from the center to the edge of the slab in three separate regions. The optimized 3D solid subgrade model resulted in better agreement with experimental strains.