Experimental Study Of Direct Shear Behaviors Of Sand Mudstone Mixed Filler In Port Area

Sand mudstone mixed filler is a kind of mixed filling soil,which has been widely applied,experimental study of direct shear test on strength characteristics of sand mudstone mixed filler in port area is a scientific significance and engineering practical value.The paper which is based on the financial supports from the National Natural Science Foundation of China “Mechaism and evolutionary process of deterioration on a sandstone-mudstone particle mixture induced by periodic saturation(No.51479012)”,through indoor experiment,the direct shear test of sand mudstone mixed filler which is related influencing factors of shear strength properties were studied.Based on experimental research,it discussed the shear strength characteristics of sand mudstone mixed filler,in the influence of the particle gradation,mudstone particle content,dry density,moisture content of sample,soaking time,periodic immersion times,reciprocating shear cycles.The paper research results are as follows:(1)The relationship between the shear strength parameters and particle gradation,mudstone particle content,dry density,moisture content were found out.The influence of paryicle gradation,cohesive force is a trend of increase with the decrease of the first,with the increase of particle size distribution of the eigenvalues d50?d60,with the increase of the curvature coefficient Cc and the asymmetrical coefficient Cu,it is a trend of decrease with the increase of the first.internal friction angle of the present trend is the contrary;The influence of mudstone particle concentration,along with the increase of mudstone particle,concentration cohesive force is a trend of decrease with the increase of the first,internal friction angle is a trend of decrease;The influence of dry density,with the increase of dry density,the cohesive force is the trend of decrease,internal friction angle showed a trend of increase.The influence of moisture content,cohesive force is a trend of decrease with the increase of the first,internal friction angle is a trend of increase with the decrease of the first.(2)The relationship between the shear strength parameters and particle gradation,mudstone particle content,dry density were found out.The results are consistent with unsaturated condition;Studying the effect of wet water on sand mudstone mixed filler with the influence of shear strength parameters,cohesive force of sand mudstone mixed filler in the saturated state in general is less than its value in unsaturated condition,internal friction angle of the present trend is the contrary.(3)The influence between the shear strength parameters and soaking time,periodic immersion times were found out.The influence of soaking time,the longer the soak time,cohesive force is less,internal friction angle is bigger,logarithmic function fitting are available;the influence of periodic immersion times,the more periodic immersion times,the lower the cohesive force,the bigger internal friction angle.(4)The influence between reciprocating shear shear strength and moisture content were found out.When moisture content is constant,with the increase of reciprocating shear cycles,the shear strength indexes shows the tendency of decrease;When reciprocating shear cycles is constant,with the increase of moisture content,cohesive force is a trend of decrease with the increase of the first,internal friction angle is a trend of increase with the decrease of the first.