杨 倩1,贾恒瑞2,陈宗平3,4
杨倩,贾恒瑞,陈宗平.火灾高温后混凝土剩余强度及本构方程研究[J].混凝土与水泥制品,2022(3):28-33.
YANG Q,JIA H R,CHEN Z P.Study on Residual Strength and Constitutive Equation of Concrete After Elevated to High Temperatures[J].China Concrete and Cement Products,2022(3):28-33.
火灾高温后混凝土剩余强度及本构方程研究
杨 倩1,贾恒瑞2,陈宗平3,4
杨倩,贾恒瑞,陈宗平.火灾高温后混凝土剩余强度及本构方程研究[J].混凝土与水泥制品,2022(3):28-33.
YANG Q,JIA H R,CHEN Z P.Study on Residual Strength and Constitutive Equation of Concrete After Elevated to High Temperatures[J].China Concrete and Cement Products,2022(3):28-33.
摘 要:为了深入研究工程建设中几种C25~C40强度等级混凝土经历火灾高温后的力学性能变化规律,提出了相对精确的剩余强度计算方法和受压本构方程,以经历温度、混凝土强度等级、恒温时间为变化参数,设计并完成了120个棱柱体试件的轴压试验,分析了各变化参数对其峰值应力、轴压刚度及耗能能力的影响规律,并给出了相应的剩余强度计算公式和轴压应力-应变本构方程的参数取值。结果表明,各试件的峰值应力、轴压刚度及耗能能力均随经历温度的升高而逐渐降低,随混凝土强度等级的提升呈现先小幅降低而后升高的变化趋势;增加恒温时间对试件的轴压力学性能不利,但影响程度不大。
Abstract: In order to further study the mechanical properties change rule, more accurate residual strength calculation method and compression constitutive equation of C25~C40 concrete after high temperature are put forward, taking the experience temperature, concrete strength grade and constant temperature time as variable parameters, and the axial compression tests of 120 specimens were designed and completed. The influence of various parameters on the peak stress, axial compression stiffness and energy dissipation capacity was analyzed. The corresponding residual strength calculation formula and the parameter values of axial compression stress-strain constitutive equation were given. The results show that the peak stress, axial compression stiffness and energy dissipation capacity of the specimens decrease gradually with the increase of temperature, and it decrease slightly at first and then increase with the increase of concrete strength grade. Increasing the holding time is unfavorable to the axial compression mechanical properties, but the effect is not significant.
版权所有:中国混凝土与水泥制品网 苏ICP备10086386号 网站建设:中企动力 苏州