岩土工程学报Issue(4)：608-614,7.DOI:10.11779/CJGE201504005
冻融及细粒含量对粗粒土力学性质影响的试验研究
Influences of freeze-thaw and fines content on mechanical properties of coarse-grained soil
摘要
Abstract
For the promotion and application of coarse-grained soil fillings in the railway subgrade in frozen regions, the shear strength properties of coarse-grained soil with fines content under freeze-thaw cycles are directly related to the subgrade stability. The influencing rules of freeze-thaw cycles, fines content and confining pressure on the shear strength properties of coarse-grained soil are therefore thoroughly studied and analyzed in laboratory tests. The results show that with the increasing increment of fines content, the stress-strain curve of coarse-grained soil changes from strain-softening before freeze-thaw cycles to strain-hardening after freeze-thaw cycles. With the increasing of fines content, the cohesion function of fines effectively enhances the shear strength of coarse-grained soil before freeze-thaw cycles, but the frost heave properties of fines decrease the shear strength of coarse-grained soil after freeze-thaw cycles. The shear strength indexes of coarse-grained soil decrease and then are steady after 6 freeze-thaw cycles. The confining pressure effectively enhances the shear strength of coarse-grained soil. Finally, the reasonable fines content of 5% is recommended for the railway subgrade coarse-grained soil fillings in frozen regions, and the mechanical indexes of the 6th freeze-thaw cycle are suggested for the engineering design values.关键词
粗粒土/冻融循环/细粒含量/应力-应变关系/抗剪强度指标Key words
coarse-grained soil/freeze-thaw cycle/fines content/stress-strain relationship/shear strength index分类
建筑与水利引用本文复制引用
卜建清,王天亮..冻融及细粒含量对粗粒土力学性质影响的试验研究[J].岩土工程学报,2015,(4):608-614,7.基金项目
国家自然科学基金项目（51208320）；河北省自然科学基金项目（E2013210040）；中国铁路总公司科研课题（2014G003-F）；河北省高校拔尖人才项目 （）
