压实黄土状填土抗剪强度指标的影响因素探讨

Discussion on shearing strength influencing factors of compacted loess-like backfill

黄土因特殊的工程特性长期为众多科研人员研究,但黄土状粉土压实后的力学性能涉足较少。对山西吕梁某地压实黄土状粉土进行24组直剪试验,得到了不同含水率和干密度条件下的抗剪强度指标。通过对抗剪强度指标c、φ的变化趋势进行统计分析,得到了压实黄土状粉土抗剪强度指标随含水率和干密度变化的线性趋势方程,讨论了含水率和干密度对压实黄土状粉土抗剪强度指标的影响。结果表明:含水率不变时,压实黄土状粉土的c、φ值均随干密度的增加而增大;干密度不变时,c、φ值均随含水率增大而减小。

Loess has been studied by many researchers due to its special engineering properties.However,very limited literatures are available about the mechanics properties of compacted silt.To investigate the performance of compacted loess-like silt,24 sets of direct shear tests are conducted on the samples taken from compacted soil site in Lüliang,Shanxi.The shearing strength indexes including the cohesion and internal friction angle in different water contents and dry density levels are obtained from the tests.The changing tendency of cohesion and internal friction angle are linearly regressed and analyzed.The linear tendency equation are gotten and summarized.It is drawn out that both cohesion and internal friction angle increase with the increase of dry density when water content keeps constant.While dry density keeps constant,the cohesion and internal friction angle slightly decrease with the increase of water content.