Numerical investigation on cracking risk of continuous reinforced concrete pavements

A continuous reinforced concrete pavement (CRCP) system is designed without construction joints; thus, its cracking risk due to changes in drying and thermal conditions is higher than that of other concrete pavement systems. This study aimed to simulate the deformation behavior of CRCP with different admixtures, such as fly ash (FA), blast-furnace slag (BFS) and expansive additive (EA) and evaluate the cracking risk of CRCP using cracking index. The numerical model was verified by comparing with the strain behaviors of three 40 m long CRCPs manufactured using ordinary Portland cement (OPC case), OPC and FA with EA (FA+EA case), and BFS cement with EA (BB+EA case) measured in the experiment. The simulation results were in good agreement with the experimental results; the shrinkage strains of CRCP with FA+EA and BB+EA cases were less than that with OPC case because EA was effective in compensating for shrinkage. Based on the verified model, additional simulations of CRCPs exposed to mild and severe temperatures were conducted, followed by an evaluation of their cracking risks with cracking index. The simulation results showed that larger strain and stress occurred under severe environmental conditions, resulting in a higher cracking risk.