钙质砂的准一维应变压缩试验研究

Experimental study on quasi-one-dimensional strain compression of calcareous sand

利用?100 mm的Hopkinson压杆研究了不同预压力条件下,受侧限约束的钙质砂在500～800 s^(-1)应变率范围、0～200 MPa压力范围内的动态力学特性,并利用HUT106D万能材料试验机研究了相同条件钙质砂在2×10^(-3) s^(-1)应变率、0～120 MPa压力范围内的静态力学特性。研究发现,当再次加载超过一定值后,预压力对钙质砂力学特性的影响不大;Tait物态方程可以描述钙质砂的静态容变关系及高压下的动态容变关系;钙质砂的体积压缩过程存在应变率效应。

The 100 mm split Hopkinson pressure bar was used to study the dynamic mechanical properties of the calcareous sand confined by confinement at strain rates ranging from 500 to 800 s.1 and pressures ranging from 0 to 200 MPa under different pre-pressures.The static mechanical properties of calcareous sand under the same conditions were investigated in the strain rate of 2×10^-3 s^-1 and the pressure range of 0.120 MPa by using HUT106D universal material testing machine.It is found that the pre-pressure value has little effect on the mechanical properties of calcareous sand when the load is more than a certain value;Tait equation of state can describe the relationship between hydrostatic pressure and volume strain of calcareous sand in static state and the dynamic state under high pressure;the volumetric compression process of calcareous sand shows a strain rate effect.