A Strength Damage and Fatigue Life Prediction Model of Pavement Cement Concrete under Loading Low-Temperature Drying Conditions

After defining the fatigue damage variable and constructing the residual flexural strength damage model, nonlinear mathematical equations of residual flexural strength and parameters, such as number of loads and function time in low-temperature and dry environment, were established to research residual flexural strength and fatigue life of cement concrete pavement in northern cold regions under low-loading and temperature drying conditions, to identify mechanism of fatigue damage in concrete pavements and residual life prediction model, and to verify accuracy of the model through experiments. These equations can better reflect laws governing mechanical property damage of concrete pavements after fatigue. The S-N fatigue life curvilinear equation and failure probability were introduced to analyze fatigue life of concrete pavements. Results indicate that the single logarithmic equation can be used to predict fatigue life of concretes with different failure probabilities, and in this case, the fatigue life curve conforms to the Weibull distribution function. This paper also provides specific double-parameter Weibull distribution function under loading low-temperature drying conditions.