【摘要】 在大型三轴静、动态电液伺服试验机上对66个立方体混凝土试件进行一向恒定侧压的动态压缩试验。四组试验的侧向恒定压力分别为单轴静态抗压强度的0、30.5%6、1.0%9、1.5%,加载速率分别为10-5s-1、10-4s-1、10-3s-1、10-2s-1四个量级。试验表明,随着应变速率的提高,不同恒定侧压下混凝土的破坏强度均有提高。在较高的恒定侧向压力下,混凝土材料对应变速率的敏感程度降低;在较高应变速率下,恒定侧压对混凝土破坏强度的加强作用也有所减弱。更多还原

【Abstract】 The dynamic compressive test of 66 cubic concrete specimens was carried out on the servo static-dynamic triaxial test machine developed by Dalian University of Technology.The effect of strain rate and lateral confining pressure on the dynamic strength and fracture pattern was studied.The lateral confining pressures were kept constantly with 0,30.5%,61.0% and 91.5% of static uniaxial strength respectively and the strain rate varied from 10^-5s^-1 to 10^-2s^-1.It is revealed that the ultimate strength under any biaxial loading state increases with the increase of strain rate.The strain rate sensitivity of concrete tends to decrease with higher lateral confined stress.The enhancement effect of constant confining pressure on ultimate strength becomes weak at high strain rate.A unified formula is suggested to express all the factors affecting the dynamic properties of concrete under biaxial loading state.更多还原