冻融循环作用下石灰改良粉砂土力学性能研究

吉林建筑大学 测绘与勘查工程学院,长春 130118

粉砂土,石灰改良,冻融循环,抗剪强度

Study on freeze - thaw cycles on mechanical properties of silty soil improved by lime
WANG Li-xia,ZHANG Xin-yue,ZHANG Yun-long,WANG Jing,SUN Shuang,HAN Bing

WANG Li-xia,ZHANG Xin-yue,ZHANG Yun-long,WANG Jing,SUN Shuang,HAN BingSchool of surveying & prospecting engineering,Jilin Jianzhu university,Changchun 130118,China

silty soil,lime improved,freeze-thaw cycle,shear strength

备注

冻融循环模拟季冻区气候条件,在最佳含水率条件下,通过不固结不排水的三轴试验,研究不同石灰掺量(0%,4%,6%,8%,10%)、冻融次数(0,1,2,3,4,5,6,8,10,12)对粉砂土抗剪强度参数黏聚力、内摩擦角的影响.试验结果表明.加入石灰后.粉砂土的最佳含水率明显增大,最大干密度减小.粉砂土的黏聚力和内摩擦角随石灰掺量增加而增大,掺灰量超过8%时,黏聚力增长趋势开始下降.冻融作用对内摩擦角的影响不大.石灰改良粉砂土掺灰量在6% ~8%范围内,其经济效果最佳.上述结果为季冻地区石灰改良路基粉砂土提供了参考依据.

The freeze-thaw cycle simulates the climatic conditions in the seasonal frozen zone.Under the condition of optimal water content,the effects of lime content(0%,4%,6%,8%,10%)and freeze-thaw cycles(0,1,2,3,4,5,6,8,10,12)on the cohesive strength and internal friction angle of the silty soil were studied by the unconsolidated un-drained tri-axial test.The test results show that after adding lime,the optimum moisture content of silty soil increases and the maximum dry density decreases.The cohesive force and internal friction angle of silty soil increase with the increase of lime content.After the ash content exceeds 8%,the growth trend of cohesion begins to decrease.The effect of freezing and thawing has little effect on the internal friction angle.The ash content of lime-modified silt sand is the best in 6% ~ 8%,which provides a reference for the lime-modified sub-grade silt in the seasonal frozen area.