Corner Stress Analysis of Jointed Concrete Pavements

Abstract

Because corner breaks are one of the major structural distresses in jointed concrete pavements, the ILLI-SLAB finite-element program was used to analyze the critical corner stresses of concrete pavements under different loading conditions. Subsequently, the effects of a finite slab size, different gear configurations, a widened outer lane, a tied concrete shoulder, and a second bonded or unbonded layer were considered. Based on the principles of dimensional analysis and experimental designs, the dominating mechanistic variables were carefully identified and verified. The resulting ILLI-SLAB stresses were compared with theoretical Westergaard solutions to develop adjustment (multiplication) factors. A new regression technique (projection pursuit regression) was used to develop prediction models to account for these theoretical differences and to instantly estimate the critical corner stresses. A practical application example illustrating the use of the prediction models was also provided and carefully verified using the ILLI-SLAB program. The research findings can be used practically for various designs and analyses of jointed concrete pavements based on theoretical considerations. Not only can the use of these stress prediction models reduce the possibility of obtaining incorrect results due to the improper use of the finite-element model, but it can also reduce the complicated computation time significantly. Furthermore, the critical bending stresses can be conveniently, accurately, and—best of all—instantly calculated through the use of these stress prediction models.