The Effect Of Freeze-thaw Cycles On Silty Clay Research On The Effects Of Shear Strength Indexes

This paper regards silty clay with typical frost heave characteristics in Harbin asthe research object, and studies the physical and mechanical change rule of differentmoisture content and different dry density silty clay under different freezing temperaturefrom the view of freezing and thawing, and establishes multiple linear regression modeland BP neural network model of shear strength parameters according to theexperimental data. The research achievements are as follows: The cohesive strength ofsilty clay is decreased and internal friction angle is the opposite after thawing. Thecohesive strength of silty clay increase and the internal friction angle decrease with thedecreasing of freezing temperature; the cohesive strength and internal friction angle ofsilty clay decrease with the increasing of moisture content; the cohesive strength andinternal friction angle of silty clay increase with the increasing of dry density; thecohesive strength of silty clay decrease and the internal friction angle increase with theincreasing of freezing-thawing cycles. The shear strength indexes values of silty clayare increased after freezing, cohesive strength and internal friction angle are directlyproportional to dry density and inversely proportional to the freezing temperature andmoisture content. BP neural network model can accurately describe the inner non-linerrelationship between shear strength indexes and moisture rate、dry density and freezingtemperature.