Study On Stochastic Predicting Method For The Freeze Proof Durability Of Concrete Based On Damage Theory

The traditional predicting methods for the service-life of concrete are established, aiming to different damage factors. Commonly, the engineering in the field is subjected multiple damage factors. It is very difficult to establish a predicting model for the service-life of concrete which has taken the influence of all the damage factors into account.In this paper, the failed mechanism of concrete under different damage factors is not considered. A damage constitutive relation of common durability of concrete is established based on damage mechanics theory. By analyzing the cumulative fatigue damage of concrete using statistic theory, the multi-Weibull distributional damage model of concrete is carried out. Therefore, a stochastic predicting method for common durability of concrete is presented, which can be used for the concrete being subjected any damage factor or several damage factors. Then the service-life of concrete can be predicted based on reliability method.Based on the stochastic predicting method for common durability of concrete, a stochastic predicting method for the freeze proof durability is established. The AE cleave experiment and the accelerated freeze-thaw cycles experiment have been carried out. The freeze-thaw damage of concrete is calculated by using the predicting model, which testify the applicability of the model. Finally, the quantitative design method for the freeze proof durability of concrete is suggested, according to the present condition of the country.