高应变率下灰砂比对全尾胶结充填体力学性能影响

为研究采矿扰动下灰砂比对全尾胶结充填体力学响应,预制了三组不同灰砂比的全尾砂胶结充填体试件,利用ф50 mm SHPB试验系统,对预制试件进行单轴冲击试验,试验结果证明:全尾砂胶结充填体对弹性波传播有较强的反射和阻尼作用;在较高应变率下,试件强度则表现出快速软化;软化试件在18μs左右即达到峰值应力;试件动态抗压强度等参数变比均随应变率的增加而增大.灰砂比越高,试件的极限动态抗压强度等参数越大;在相同应变率下,试件的动态抗压强度等参数的增加反而降低.试件的破坏形式为压碎破坏,在相同应变率作用下,水泥含量越少,试件的破坏程度越高.

Mechanical Properties of the Total Tailing Cemented Backfilling Impacted by Cement-Sand Ratio Under High Strain Rate

In order to study the dynamic mechanical behavior of the total tailing cemented backfilling under the mining disturbance impacted by cement-sand ratio, three groups of different cement-sand ratio specimens of total tailing cemented backfilling were precasted, and the precast specimens under uniaxial impulse by using the  50 mm SHPB experimental system was tested.The test results show that the total tailing cemented backfilling has strong reflection and damping effect on elastic wave propagation.At the high strain rate, specimens exhibit the behavior of rapid softening and the softening specimens reach to peak strength at around 18 μs.The dynamic compressive strength increases with an increase instrain rate. The higher cement-sand ratio, the greater the ultimate dynamic compressive strength. At the same strain rate, the dynamic compressive strength of the specimens decreases with the increase of cement content.At the same strain rate, the lower the cement content, the more severely the specimens fail with the form of crushing destruction.