再生混凝土疲劳可靠度及疲劳寿命预测  

Research on Fatigue Reliability and Fatigue Life Prediction of Recycled Aggregate Concrete

作　　者：钟楚珩 龙宇华 周金枝 吴维熙 ZHONG Chuheng;LONG Yuhua;ZHOU Jinzhi;WU Weixi(School of Civil Engineering,Architecture and Environment,Hubei University of Technology,Wuhan 430070,China;State Key Laboratory for Health and Safety of Bridge Structures,Wuhan 430034,China)

机构地区：[1]湖北工业大学土木建筑与环境学院,武汉430070 [2]桥梁结构健康与安全国家重点实验室,武汉430034

出　　处：《工业建筑》2022年第4期140-145,83,共7页Industrial Construction

基　　金：桥梁结构健康与安全国家重点实验室项目(BHSKL19-04-KF)。

摘　　要：为了研究再生混凝土的弯曲疲劳性能和疲劳可靠度,对普通混凝土(NAC)和再生混凝土(RAC)进行不同应力水平下(S=0.6、0.7、0.9)弯曲疲劳试验,获得不同应力水平下试件的纵向应变和疲劳寿命。并对疲劳寿命进行两参数Weibull分布检验,建立的S-N-P_(f)方程。再依据对数疲劳寿命一般遵循对数正态分布的规律,基于Palmgren Miner疲劳模型,得出可靠度计算式,对混凝土疲劳可靠度进行分析。结果表明:在不同应力水平下,RAC的疲劳寿命较NAC来说较小,纵向应变较NAC较大,抗弯疲劳性能较NAC差,其疲劳可靠度也低于NAC。且在对NAC的分析中假设疲劳寿命服从Weibull分布所得不同可靠度下的预测疲劳寿命,比假设服从对数正态分布更接近疲劳寿命临界值,而在对RAC的分析中,两者结果相差不大。The flexural fatigue tests of natural aggregate concrete(NAC)and recycled aggregate concrete(RAC)were investigated at three different stress levels(S=0.6,0.7,0.9)to study the fatigue properties and fatigue reliability of recycled aggregate concrete,the longitudinal strain and fatigue life at different stress levels were obtained.The two-parameter Weibull distribution was analyzed,and the S-N-P_(f)equation was established.And since the logarithmic fatigue life generally follows a lognormal distribution,based on the Miner fatigue model,the reliability formula was derived and the fatigue reliability was calculated.The results showed that under different stress levels,the fatigue life of RAC was smaller than that of NAC,the longitudinal strain of RAC was larger than that of NAC,the flexural fatigue resistance and the fatigue reliability of RAC were lower than that of NAC.It was assumed that the fatigue life obeyed the Weibull distribution,the predicted fatigue life under different reliability was closer to the critical value than if it obeyed the lognormal distribution in the analysis of NAC.The results were not much different in the analysis of RAC.

关 键 词：再生混凝土 弯曲疲劳寿命 两参数WEIBULL分布 S-N-P_(f)方程 疲劳可靠度 预测疲劳寿命 

分 类 号：TU528[建筑科学—建筑技术科学]