摘要
本文对掺引气剂混凝土进行了不同次数快速冻融试验,用电子显微镜观察了经受不同次数冻融循环后混凝土微观结构的变化,并进行了6种应力比下的双轴拉-压试验,观察了试件破坏形态,测得了混凝土试件的抗拉强度和抗压强度。试验发现,掺引气剂混凝土在双轴拉-压荷载作用下,其抗拉强度和抗压强度均随冻融循环次数的增加而明显降低。在此基础上,分析了双轴拉-压极限强度随冻融循环次数的变化规律,并在主应力空间和八面体应力空间建立了同时考虑冻融循环次数和拉压比的破坏准则。
The variation of concrete microstructure after various cycles of freeze-thaw was inspected by using electron microscope and the strengths of concrete samples under biaxial tension-compression with six tension-compression ratios were obtained by using a large static-dynamic triaxial test installation. The failure patterns of concrete specimens are recorded. It is found that the ultimate strength of concrete is reduced remarkably following the increase of freeze-thaw cycle and the relationship between strength and freeze-thaw cycle is analyzed. On this basis, the failure criterion of concrete simultaneously considering the freeze-thaw cycle and tension-compression ratio in principle stress space and octahedral space is established.
出处
《水利学报》
EI
CSCD
北大核心
2006年第8期932-937,共6页
Journal of Hydraulic Engineering
基金
国家自然科学基金资助项目(50479059)
关键词
引气混凝土
冻融循环
双轴拉-压
破坏准则
air-entrained concrete
cyclic freeze-thaw test
biaxial tension-compression strength
failure criterion
