Study On Shear Strength Of Typical Heavy-duty Compacted Standard Soil In Shijiazhuang Of Luochuan And Its Engineering Application

The index of shear strength of remolded compacted soil is an important parameter for analyzing the stability of high embankment slopes and settlement of subgrade.The current study on the loess shear strength index is limited to a specific stratum in a region(Q3 or Q2).However,the landfill of high embankments and the management of large slopes must face the engineering nature of the entire section.Therefore,this paper studies the shear strength of loess-paleosolic soil in three different profiles of Shi jiazhuang of Luochuan,Wutian of Weinan,and Kong jiayuan of Xifeng.The main achievements are as follows:(1)The cohesion and internal friction angles of loess-paleosol in different layers of Luochuan Shijiazhuang,Weinan Wutian,and Xifeng Kongjiayu sections under optimal moisture content are measured(The degree of compaction was 90%,92%,94%,96%,respectively).Analyze and compare the differences in shear strength index due to different geological ages.The difference in shear strength between remolded compacted loess and ancient soil are analyzed.Use quadratic polynomial to fit the relationship between shear strength index and compaction degree of remolded compacted soil.Analyze and compare the differences in shear strength index values due to different profiles.(2)Taking Loess in the late Pleistocene in Shijiazhuang Section of Luochuan as an example,the effects of water content,compaction,clay content and shear rate on the remolded compacted loess are summarized and analyzed.(3)The influencing factors of embankment slope stability such as slope height,slope rate,section form,and filler properties are analyzed.An optimized slope ratio for high embankment filling using loess of the entire Pleistocene and late Pleistocene in Shijiazhuang Section of Luochuan is proposed.Based on the slope stability analysis of the Holocene and Malan loess layers simulated in the Shijiazhuang Section of Luochuan,the optimization method for the stability analysis of embankment slopes filled with remolded soil is summarized.