湿筛二级配大坝混凝土双轴动态受压特性试验

Experimental study of two-graded wet-screened dam concrete under dynamic biaxial compression loading

研究湿筛混凝土在双轴动态受压荷载作用下的动态力学特性,建立湿筛混凝土双轴动态受压强度准则。利用大型液压伺服静、动态三轴试验设备,对150 mm×150 mm×150 mm湿筛二级配大坝混凝土立方体试件进行等比例双轴动态受压加载试验,应变速率为10^(-5)~10^(-2) s^(-1)。湿筛混凝土双轴动态受压强度及动态弹性模量随应变速率的增大而提高,湿筛混凝土双轴受压强度的动态增长幅度与水工大骨料混凝土相当,均高于相同条件下的普通混凝土。通过对试验数据的拟合,得到湿筛混凝土双轴动态强度准则,为大体积混凝土结构进行非线性分析、探索动态强度机理提供数据支持和依据。

The dynamic mechanical properties of wet-screened concrete under biaxial dynamic compressive loading were studied, and the dynamic strength criterion were established.By the large static and dynamic triaxial hydraulic servo test equipment,the dynamic experiments of wet-screened concrete cube specimens（ 150mm×150mm×150mm） were conducted with strain rates of 10^-5-10^-2s^-1. Dynamic biaxial compressive strength and dynamic modulus of elasticity were increased with the increase of strain rate, and its growth rate was higher than the ordinary concrete under the same conditions.By fitting the test data,the dynamic strength criterion of wet screened concrete was obtained,which could provide data support and basis for nonlinear analysis of mass concrete structures and exploring the mechanism of dynamic strength.