通过对6种新型墙体材料和烧结普通砖在不同冻融循环次数(0,25,50和75次)下的试验,研究新型墙体材料的质量损失率、强度损失率与循环次数的关系,结合新型墙体材料冻融损伤失效过程,建立新型墙体材料的冻融损伤时变可靠度计算模型。研究结果表明:以混凝土实心砖为例,随着时间的推移,混凝土实心砖的冻融循环时变可靠指标逐渐变小,变化趋势呈抛物线型。通过模型可预测新型墙体材料的冻融循环寿命,为新型墙体材料的冻融损伤计算提供依据,为维护部门提供决策依据,降低失效风险。
Freeze-thaw tests were made for six kinds of the new wall materials and clay brick,and the number of freeze-thaw cycles is 0,25,50 and 75.By studying relationship of rate of mass loss and cycle numbers or rate of strength loss and cycle numbers,calculating damaging model of new-type walling materials was found based on time-depending reliability under action of freeze-thaw cycle.The result shows that time-depending reliability index of concrete solid brick in freeze-thaw cycles is gradually changing smaller,with time going by,and changing tendency is parabola.Using the model,the freeze-thaw cycle life of the new type wall materials can be predicted,which supplies basis of freeze-thaw damaging calculation for the new-type wall materials,and reduces risk.