冻融循环作用下混凝土材料寿命评估方法

Evaluation method for the service life of concrete under the freeze-thaw action

摘要:

为判断服役混凝土材料能否在设计基准期内实现预定的使用功能,提出基于材料学的计算准则来评估冻融循环作用下混凝土材料的寿命.推导两参数Weibull分布的概率分布函数和相对动弹性模量损失率的关系,建立基于概率论和损伤理论的混凝土冻融损伤模型,并论证其适用性.在此模型基础上进一步提出混凝土等效冻融损伤模型,将各混凝土冻融循环试验的结果统一.结果表明,采用基于概率论和损伤理论建立的混凝土冻融损伤模型预测混凝土材料寿命是合适的.

Abstract:

To estimate whether the concrete could complete the preconcerted service function,based on the material science rule,this paper proposes a calculation rule to estimate the service life of the concrete under the freeze-thaw action.The relationship between probability distribution function of two-parameter Weibull distribution and percentage loss of relative dynamic modulus is deduced.The applicability of the freeze-thaw damage model of concrete based on the theory of probability and damage mechanics is demonstrated.And the equivalent freeze-thaw damage model of concrete is established,which could unify the results of the freeze-thaw experiment of concrete.The results show that the freeze-thaw damage model of concrete is appropriate to estimate the service life of the concrete structure.