Asphalt Concrete Pavement Overlay Mechanical Analysis

In this paper, MSC.NASTRAN software package was empolyed to analyse responses of cracking , potholes and rutting under axle load which are representatives of each of the following categories: cracking, permanent deformation(subsidence, rut, corrugation, upheaval), surface distress(potholes, looseness).Firstly, the influence of different patching material and the load positions on the mechanical behavior of pothole sewing wall were analysed. The structural response of the pothole wall before and after spraying sticky oil was compared. Secondly, based on the fracture mechanics, by means of finite element method, the mechanism of reflective crack propagation under traffic loadings were studied. The author also analyse the factors influcencing the crack growth. Finally, the strength state of the old pavement with rutting which doesn't repair and overlayed asphalt concrete was simulated and the influence of overlay thickness on rutting was also studied.On the basis of the numerical analyse of the distresses , rational and feasible measures for asphalt pavement maintenance were recommended.