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通过对皖北矿区3个煤矿砂岩岩样加工成厚径比为0.5的圆盘试件,利用变截面分离式Hopkinson压杆(SHPB)试验装置,采用不同加载冲击气压驱动撞击杆高速运动,对圆盘试件实施不同加载速率下的动态劈裂拉伸试验,得到了3种砂岩试件的动态拉伸应力和应变率等力学参数,并与静态劈裂拉伸试验结果进行对比,分析了砂岩圆盘试件动静态劈裂破坏形态、动态拉伸应力与加载速率相关性规律;得到了试验冲击气压范围内砂岩动态拉伸应力强度与平均应变率之间近似为乘幂函数关系,比其静态拉伸应力强度提高2～3倍。对砂岩动静态拉伸力学性能研究做了一些有益的探索。
The sandstone samples from 3 coal mines in the northern part of Anhui Province were processed into disc specimens with an aspect ratio of 0.5. The split Hopkinson pressure bar (SHPB) test device was used to drive the impact bar at different speeds. The dynamic tensile splitting tensile tests under different loading rates were carried out on disc specimens. The dynamic tensile stress and strain rate of the three kinds of sandstone specimens were obtained and compared with the static splitting tensile test results The relationship between dynamic and static splitting failure modes, dynamic tensile stress and loading rate of sandstone disk specimens was obtained. The relationship between the dynamic tensile stress intensity and the average strain rate of sandstone in the range of experimental impact pressure was approximated by the power function, The tensile strength of static tensile strength increased by 2 to 3 times. Some useful explorations have been made on the dynamic and static tensile mechanical properties of sandstone.