Xi'An Research Institute of High-Tech, Xi'an, China.
Chongqing Chengtou Road and Bridge Administration Co., Ltd, Chongqing, China.
PLoS One. 2022 Jul 14;17(7):e0271266. doi: 10.1371/journal.pone.0271266. eCollection 2022.
Loess has the characteristics of large porosity, loose structure, uniform composition and strong collapsibility. When encountering heavy rainfall and irrigation prone to saturation, resulting in loess landslides, roadbed subsidence and dam instability. In order to study the effect of dry density and shear rate on the shear strength of saturated remolded loess, the consolidated undrained (CU) test was carried out in Yan'an City by using SLB-6A stress-strain controlled triaxial shear permeability test instrument. The shear rate, confining pressure and dry density were controlled during the test. The dry densities of the samples were 1.5 g / cm3, 1.6 g / cm3 and 1.7 g / cm3, respectively. CU tests of saturated remolded loess were carried out at different shear rates under the confining pressures of 100 kPa, 150 kPa and 200 kPa, respectively. It is found that the stress-strain curve of saturated remolded loess gradually moves upward with the increase of dry density. With the increase of dry density, the cohesion and internal friction angle of remolded saturated loess samples increase. At the same shear rate, with the increase of dry density, the deviatoric stress of the specimen increases significantly.
黄土具有大孔隙率、疏松结构、均匀组成和强烈的可压缩性。遇强降雨和易饱和的灌溉时，会导致黄土滑坡、路基下沉和水坝失稳。为了研究干密度和剪切速率对饱和重塑黄土抗剪强度的影响，利用 SLB-6A 应力应变控制三轴剪切渗透试验仪在延安市进行了固结不排水（CU）试验。试验中控制了剪切速率、围压和干密度。试样的干密度分别为 1.5 g/cm3、1.6 g/cm3 和 1.7 g/cm3。在围压分别为 100 kPa、150 kPa 和 200 kPa 下，对不同剪切速率下的饱和重塑黄土进行了 CU 试验。结果表明，随着干密度的增加，饱和重塑黄土的应力-应变曲线逐渐向上移动。随着干密度的增加，重塑饱和黄土试样的黏聚力和内摩擦角增大。在相同的剪切速率下，随着干密度的增加，试样的偏应力显著增加。
