石英砂粒径对水合物沉积物力学性质的影响

Effects of quartz sand particle sizes on mechanical properties of hydrate sediments

利用自主研发的水合物沉积物原位合成与力学性质测试的高压低温三轴仪,通过多级加荷的试验方法,以不同粒径的砂粒作为沉积物骨架进行三轴压缩试验,得到了剪切过程的应力-应变关系曲线,以及不同粒径尺寸沉积物的强度,还有剪切过程中的体积变化关系。结果表明:含水合物沉积物强度随着沉积物粒径尺寸的增大而增强;在降压剪切过程中,所有粒径的水合物沉积物式样均有明显的剪缩现象。

Triaxial tests are carried out by the multistage loading method on a self-developed high-pressure and low-temperature triaxial apparatus for in-situ synthesis and mechanical properties testing of hydrate sediments.Quartz sand particles with different sizes are served as sediment scaffolds.The stress-strain curves,sediment strength with different particle sizes and the volume variation relationship during the shearing process are obtained.The results show that the strength of the methane hydrate sediment increases as the particle size of the sediment increases.In the processes of depressurization and shearing,the hydrate sample will have obvious shear shrinkage regardless of the particle size of the sediment.