Performance evaluation and prediction of asr-deteriorated concrete median barrier subjected to impact loading

CMBs (Concrete Median Barriers) in service along expressways are deteriorated by deicing chemicals, the freeze-thaw and ASR (Alkali-Silica Reaction), leading to a decrease in structural performance of CMBs subjected to impact loads of moving vehicles. It is necessary to provide appropriate maintenance activities to deteriorated CMBs in order to improve the safety of expressway users. This paper aims at evaluating structural performance of degraded CMBs and suggesting the timing for rehabilitation. Two deterioration models for the CMBs were proposed: ① the depth 30 mm deterioration model and ② the stage deterioration model, based on field investigations. Numerical analysis of vehicle collisions were carried out via the proposed deterioration models with varying extents of deterioration. Results obtained from numerical simulations indicate that appropriate maintenance activities should be performed before Deterioration Stage 3, when randomly distributed cracks expand up to 750 mm from pavement surface.