水泥混凝土路面板脱空问题的数值模拟研究

One of important reasons of structural destruction of cement concrete pavements is the void the initiation and propagation under the pavement slabs, because the pavement slabs would suffer a bad stressed condition due to the void existence. The void initiation and development under pavement slabs is investigated by combining the damage theory to the finite element method to develop the numerical simulation technique. A damage constitutive model with three independent parameters is derived from the elastic damage theory. Numerical simulation is performed for the void development under the central and side slab loading conditions. The displacement, stress and damage fields are evaluated the influence of base layer stiffness on the void initiation and growth is discussed. It is seen that when the base layer stiffness reaches a critical value, the increment of base layer stiffness has no further improvement for the pavement performance. In addition, if there is a void under the slab in advance, the fatigue life of pavement slab would be greatly reduced.