Probabilistic assessment of cracking and delamination of latex modified concrete overlays on steel plate girder using monte-carlo simulation

Latex modified concrete (LMC) possesses improved cracking strength and higher durability characteristics than concrete without latex. LMC overlays are typically used to increase the service life of bridge decks. On the other hand, the increasing use of high-performance concrete (HPC) in bridge deck slabs might affect the performance of LMC overlays due to the considerable difference between LMC and HPC characteristics. In this study, numerical analysis was performed using 2D linear Finite Element (FE) model coupled with Monte-Carlo simulation to examine the effect of the characteristics of the substrate, including differential shrinkage, overlay-to-substrate stiffness ratio, and cracking capacity on the probability of cracking (POC) and the probability of delamination (POD) of LMC bridge deck overlays. In addition, 3D nonlinear FE model was constructed to assess the effect of interface cracks on the structural response of bridge deck. It was found that high differential shrinkage strains and high stiffness differences between LMC and HPC can increase tensile stresses at the interface. The probability of cracking and delamination is governed by the tensile strength of the bridge deck substrate and crack development at the interface reduces the stiffness of bridge deck significantly.