高温混凝土动态力学性能的SHPB试验研究

SHPB Test for Dynamic Mechanical Performances of Concrete at High Temperatures

采用微波炉与SHPB试验进行了高温、冲击载荷下的混凝土动态力学特性的试验;在试验结果基础上,探讨温度和应变率对混凝土的综合影响;建立了混凝土材料强度与温度和应变率之间的关系;并分析其力学机理。试验与分析结果表明:混凝土在高温下出现了塑性流动现象,这种塑性流动现象随着温度的升高而越来越明显;同时,混凝土随着温度的增加或加载速率的增加,表现出更好的韧性。

The dynamic mechanical performances of the concrete under high temperature and impact load were tested by use of a microwave oven and a split Hopkinson pressure bar(SHPB);the influences of the strain rate and temperature on the concrete was explored base on the tested result;the relations between stress and strain at the different temperatures and loading rates were established;its mechanical mechanism was analyzed.The tested and analyzed results show that the concrete as a brittle material will exhibits the plastic-flow phenomenon at high temperature,which becomes more and more obvious with the temperature increasing;the higher the temperature is or the faster the loading rate is,the higher the toughness of the concrete is.