黏质粗颗粒土固结特性及对慢剪速率的影响

Consolidation Characteristics of Viscous Coarse Particle Soil and Its Influence on Slow Shear Rates

黏质粗颗粒土慢剪剪切速率与固结时间相关。为了探索不同固结压力下适用的剪切速率,对泥岩和黄土混合料进行大型压缩试验,以固结度达到90%所对应的时间t_(90)为基准,研究试样固结特性及剪切速率确定方法。试验结果表明:试样固结系数随固结压力增加呈先迅速减小后略有增加的趋势,拐点压力附近渗透系数已趋于稳定,而压缩系数变化显著。剪切速率与固结系数呈线性关系,固结压力小于1000kPa时,剪切速率应根据固结系数进行确定,固结压力大于1000kPa时,试验可按0.03mm/min剪切速率进行。

The shear rate of viscous coarse particle soil is related to the consolidation time.To explore suitable shear rates under different consolidation pressures,large-scale compression tests are conducted on mixed samples of mudstone and loess.Based on the t_(90) corresponding to the consolidation degree of 90%,the consolidation characteristics of the samples and the determination method of shear rates are studied.The results show that the consolidation coefficient of the samples decreases rapidly at first and then increases slightly with increasing consolidation pressure,and the permeability coefficient stabilizes near the inflection pressure.The compression coefficient shows significant changes.The shear rate is linearly related to the consolidation coefficient.For consolidation pressures below 1000 kPa,the shear rate shouid be determined based on the consolidation coefficient,while for pressures above 1000 kPa,a shear rate of 0.03 mm/min can be used.