史卜涛¹,张云¹,胡磊¹,吴吉春¹,于军²,龚绪龙²
SHI Butao¹, ZHANG Yun¹, HU Lei¹, WU Jichun¹, YU Jun², GONG Xulong²

• 1:南京大学地球科学与工程学院，江苏 南京 210046
• 2:江苏省地质调查研究院，江苏 南京 210018

摘要(Abstract)：

对不同干密度的重塑饱和黏性土进行直剪试验，探讨了剪切速率对重塑饱和黏性土剪应力-剪位移曲线的影响，分析了内摩擦角随剪切速率的变化关系。试验结果表明，干密度越小的重塑土，剪切速率对其内摩擦角的影响越明显。剪切速率主要影响剪切面附近的孔隙水压力，进而影响土体抗剪强度。剪切速率越大，剪切面周围超孔隙水压力越大，使土体总强度降低。在相同的法向应力下，不同剪切速率引起的剪切面周围孔隙水压力增量与抗剪强度差值成正比关系。当剪位移为7 mm时，剪切速率越大，土颗粒位移比较平直，剪切破坏面越平整。
The shear strength of the saturated remolded clay with different dry densities is studied under different shear rates. The relationship between shear rate and the shear stress-displacement curve is discussed. The relation between internal friction angle and the shear rate is analyzed. The results show that the smaller density of soil, the more obvious effect of shear rate on the internal friction angle is. The shear rate mainly influences the pore water pressure near the shear surface. With the shear rate increasing, the excess pore water around the shear surface cannot dissipate completely, leading to the reduction of the soil strength. With the given normal stress, the increase of the pore water pressure around shear surface caused by different shear rates is proportional to the decrease of the failure shear stress. When the shear displacement is 7 mm, the faster the shear rate, the straighter the moving track of soil particles as well as the flatter the shear failure surface.

关键词(KeyWords)： 直剪试验;强度参数;剪切速率;孔隙水压力
direct shear test;strength parameters;shear rate;pore water pressure

Abstract:

Keywords:

基金项目(Foundation): 国家自然科学基金项目（41572250）；国土资源部公益性行业科研专项经费项目（201411096-03）

作者(Author): 史卜涛¹,张云¹,胡磊¹,吴吉春¹,于军²,龚绪龙²
SHI Butao¹, ZHANG Yun¹, HU Lei¹, WU Jichun¹, YU Jun², GONG Xulong²

DOI: 10.3969/j.issn.1001-1986.2017.02.016

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