高温后混凝土双轴拉-压力学特性试验研究

Experimental research on mechanical behavior of concrete under biaxial tension compression after high temperature

利用大型混凝土静-动三轴试验系统，对高温后的普通混凝土进行了5种加载比例的双轴等比例拉-压试验，给出了20～600℃范围内相应的试验数据．根据试验结果．分析了高温后混凝土双轴拉-压力学特性，发现在双轴拉-压应力状态下，各应力比下混凝土抗拉强度、峰值拉应力点处的应变均随温度的升高而下降．在此基础上，给出了抗拉强度与温度和应力比的关系武。建立了高温后混凝土双轴拉-压的强度破坏准则．

Biaxial equal scale tension-compression experiments by 5 loading ratios on the mechanical behavior of the concrete after high temperatures were made, using the large static dynamic triaxial test system for concrete. The test data of various temperaturs from 20 ℃ to 600 ℃ are reported, and the analysis on the tension-compression mechanical behavior of the concrete is performed, it is indicated that the tensile strength and strain at this strength value both drop with the rising of the temperature under each stress ratio. Based on the results, the equation of the relationship between the tensile strength and stress ratios, temperatures is proposed, and the failure criterion of the concrete under the biaxial stress state of the tension-compression after high temperatures is established.