Fatigue Performance Of Concrete Pavement

In this paper, the author has analyzed the failure process of the traditional cement concrete pavement. On the basis of fracture mechanics, the author has revealed the principle of intermediate layer's influence on concrete fatigue performance. By comparison fatigue test results, the author has found the differences between fatigue performance of cement concrete samples with an intermediate layer and that with an insulating layer. The author has proved the intermediate layer is deleterious to the fatigue performance of concrete and concrete pavement, and concluded that the insulating layer can prevent the intermediate layer from generating. The author has constituted the fatigue equation of concrete also.Based on the closing force crack-resistant model in crack tips, the author has revealed the flexible fibers' crack-resistant-wall effect in flexible fiber reinforced concrete, which has been verified by fatigue tests. The author has built the fatigue equation of flexible fiber reinforced concrete, concluded flexible fibers can remarkably improve the concrete's fatigue performance, and proved that flexible fiber reinforced concrete is a kind of excellent material for cement concrete pavement.In general, the author has made the following conclusions: Firstly, concrete pavement structure with an insulating layer is an ideal pavement structure type, which can enormously diminish the intermediate layer's influence on the fatigue performance of the concrete surface course. Secondly, flexible fibers in concrete can remarkably improved the fatigue performance of concrete, and by using flexible fibers, concrete pavement's actual service life can be prolonged.