玄武岩纤维增强再生混凝土的单轴受压疲劳试验研究

Study on Fatigue Test of Basalt Fiber Reinforced Recycled Concrete underUniaxial Compression

在素混凝土中掺入纤维能提高其抗疲劳性能.威布尔分布模型是常用的疲劳寿命预测模型.对玄武岩纤维体积掺量(RB)分别为0%,0.05%,0.10%,0.15%的玄武岩纤维增强再生混凝土(BFRRC)试件进行抗压疲劳试验研究,并用威布尔分布模型对疲劳寿命进行拟合.研究表明:在再生混凝土中掺入玄武岩纤维,能大幅度提升其疲劳寿命,尤其是在较低应力水平条件下增幅更明显.加载应力水平对BFRRC的疲劳寿命影响较大,随着加载应力水平的增大,试件承受的加载循环次数大幅度降低.通过矩估计法求得威布尔分布的参数估计值,并利用K-S检验,对不同应力水平条件下的BFRRC疲劳寿命进行假设检验,验证得到BFRRC的疲劳寿命服从威布尔分布.

Adding fibers to plain concrete can improve its fatigue resistance.Weibull distribution model is a commonly used fatigue remaining life prediction model.In this paper,the compressive fatigue tests of basalt fiber reinforced recycled concrete(BFRRC)specimens with 0%,0.05%,0.10%and 0.15%basalt fiber volume fraction(RB)were carried out,and the Weibull distribution model was used to fit the fatigue life.Studies have shown that adding basalt fiber to recycled concrete can greatly increase its fatigue life,especially under conditions of lower stress levels.The loading stress level has a great influence on the fatigue life of the BFRRC.As the loading stress level increases,the number of loading cycles that the test piece bears is greatly reduced.The parameter estimates of the Weibull distribution are obtained by the moment estimation method,and the K-S test is used to hypothesize the fatigue life of the BFRRC under different stress levels.It is verified that the fatigue life of the BFRRC obeys the Weibull distribution.