Cement concrete pavement design based on cumulative damage factor

Based on the compositive fatigue equation of load fatigue stress and temperature fatigue stress, the coverage-to-pass ratios of single-axle-single-wheel load and single-axle-double-wheel load were calculated by adopting cumulative damage factor.A direct calculating method of total cumulative fatigue damage of pavement structure produced by multi-axle load and a new design method of cement concrete pavement were put forward by replacing design axle load with cumulative damage factor.The accuracy and application feasibility of calculating fatigue damage produced by multi-axle load were done through a design example with two types of traffic volumes.Analysis result indicates that the acting times of multi-axle load at all points on the cross section of highway are different, and the peak value of cumulative damage of each axle load may be not at the same location.The thicknesses of worst pavement places under the traffic volumes calculated by the design method based on cumulative damage factor are all 22 cm, which meets the design requirement, and the thicknesses of other places can reduce according to the cumulative damage curve.Thereby, it can avoid the differences and localizations of present specification design method of concrete pavement based on standard axle load and equivalent fatigue consumption principle.