水灰比对水泥砂浆高应变率下动态抗压力学性能影响的试验研究

Influence of Water-to-cement Ratio on Dynamic Compressive Behavior for Cement Mortar under High Strain Rate

为了研究水灰比对高应变率下水泥砂浆动态抗压力学性能的影响,利用分离式Hopkinsin压杆(SHPB)装置对不同水灰比(0.4、0.5和0.6)的水泥砂浆试件进行了单轴动态抗压试验研究;应变率范围为(39.4～209.4)s-1。同时进行了静态加载试验。试验结果表明,水泥砂浆的单轴抗压强度随着应变率的增大而增大,随水灰比增大,动态抗压强度值随应变率提高而增大的越缓慢;动态抗压强度提高因子DIF随应变率的增加而增大的速度随着水灰比的增加而降低。高应变率下,水泥砂浆试件的峰值压应变与极限压应变随着应变率的增大而增大,水灰比对峰值压应变值与极限压应变值的影响不大。

Split Hopkinson pressure bar technique is presented to study the water/cement ratio effect on dy- namic compressive behavior for cement mortar under high strain rate. Using the SHPB technique to test three kinds of water/cement （0. 4,0. 5,0. 6） mortar＇ s dynamic compressive strength under high strain rate from （ 39.4 - 209.4） s- 1 . And at the same time static loading experiment is also tested. The results show that the uniaxial com- pressive strength of cement mortar increases with strain rate increasing, When the water/cement ratio increase high, the strength increases with strain rate increasing slowly. The dynamic compressive strength increasement fac- tot, namely DIF, increases with the increase of strain rate, the velocity of which decease with the increase of water cement ratio; under high strain rate, the peak compressive strain and the ultimate compressive strain increase with the increase of strain rate, while the water cement ratio has little impact on both of them.