原状黄土抗剪强度的各向异性研究
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摘要
以潼关至三门峡和石家庄至太原铁路沿线上更新世(Q_3)和中更新世(Q_2)共30组黄土原状样为研究对象。从水平向、45°方向和竖直向三个剪切面方向做直剪试验,分别测其抗剪强度指标。结果表明:原状黄土抗剪强度存在明显的各向异性,即不同方向剪切面上的抗剪强度存在明显差异,且成因不同表现出的差异性也不同。不同时代和成因的黄土不同剪切面抗剪强度基本呈现出竖直向剪切面的抗剪强度>水平向剪切面抗剪强度>45°方向剪切面抗剪强度规律。不同时代和成因的黄土抗剪强度大小关系为:Q_2~1>Q_2~(al)>Q_2~(al-pl)>Q_3~(al)>Q_3~(eol)。因此,工程设计中应重视黄土在不同剪切面上抗剪强度的差异性,以便获得安全合理的强度参数。
The Pleistocene(Q_3) and Middle Pleistocene(Q_2) thirty groups loess samples were taken from the mechanical Luoyang shovel in Tongguan to Sanmenxia, Shijiazhuang to Taiyuan and Taiyuan to Feng Ling ferry. Physical experiments and direct shear tests on dry density, void ratio, specific gravity of particles and liquid plastic limit were carried out. Direct shear tests were carried out from the horizontal direction, 45°direction and vertical direction to three shear planes, and their shear strength was measured respectively. The results show that the shear strength of loess in this area has obvious anisotropy, and the difference is also different from the cause of formation. The shear strength of different shear surfaces in different age of loess basically shows the shear strength of vertical shear surface and the shear strength of shear strength at horizontal shear strength >45° shear strength. The difference of shear strength of loess on different shear planes should be emphasized so as to obtain safe and reasonable strength parameters.
The Pleistocene(Q_3) and Middle Pleistocene(Q_2) thirty groups loess samples were taken from the mechanical Luoyang shovel in Tongguan to Sanmenxia, Shijiazhuang to Taiyuan and Taiyuan to Feng Ling ferry. Physical experiments and direct shear tests on dry density, void ratio, specific gravity of particles and liquid plastic limit were carried out. Direct shear tests were carried out from the horizontal direction, 45°direction and vertical direction to three shear planes, and their shear strength was measured respectively. The results show that the shear strength of loess in this area has obvious anisotropy, and the difference is also different from the cause of formation. The shear strength of different shear surfaces in different age of loess basically shows the shear strength of vertical shear surface and the shear strength of shear strength at horizontal shear strength >45° shear strength. The difference of shear strength of loess on different shear planes should be emphasized so as to obtain safe and reasonable strength parameters.
引文
[1] 衣浩源.原状马兰黄土抗剪强度的各向异性[D].太原理工大学,2017.
[2] 李保雄,苗天德.黄土抗剪强度的水敏感性特征研究[J].岩石力学与工程学报,2006,25(5):1003-1008.
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[4] 杨磊.黄土抗剪强度特性分析[J].水利与建筑工程学报,2010,8(3):163-166.
[5] 张沛然等.重塑黄土抗剪强度研究[J].山西建筑,2014,40(20):71-73.
[6] 安亚芳等.兰州Q4黄土各向异性的初步研究[J].岩土力学,2011,30(1):90-96.
[7] 徐善常等.甘肃定西原状Q3黄土各向异性试验研究[J].地质力学学报,2015,21(3):378-385.
[2] 李保雄,苗天德.黄土抗剪强度的水敏感性特征研究[J].岩石力学与工程学报,2006,25(5):1003-1008.
[3] 陈海明,班凤其,刘小伟.非饱和土抗剪强度指标与含水量的关系[J].合肥工业大学学报(自然科学版),2006,29(6):736-738.
[4] 杨磊.黄土抗剪强度特性分析[J].水利与建筑工程学报,2010,8(3):163-166.
[5] 张沛然等.重塑黄土抗剪强度研究[J].山西建筑,2014,40(20):71-73.
[6] 安亚芳等.兰州Q4黄土各向异性的初步研究[J].岩土力学,2011,30(1):90-96.
[7] 徐善常等.甘肃定西原状Q3黄土各向异性试验研究[J].地质力学学报,2015,21(3):378-385.