The Study On The Change Of Sheer Strength Characteristic Parameter And Soil Nail Firmness Of Effect In The Condition Of Freezing-thaw Cycling

Xinjiang has a complex geological condition and large temperature diversity in the spring and autumn. This phenomenon makes the physical and mechanical characteristics of fine soil after and before the freezing-thaw cycling. It will destroy the deep excavation conception structure of granule soil and make a lot of harm to the safety of the deep excavation conception project.By fine earth freeze-thaw simulated experiment and cut experiment in the room, this paper studied the sheer strength characteristic parameter before and after the freezing-thaw cycling, and got the change discipline of the internal cohesive force c, internal friction angleФin the different temperature range and the number of the freezing-thaw cycling, deduced the calculation formula of c,Фand T(soil nail counteract evulsion force) according to the experiment data, and compared the effect of the firmness. According to the experiment and analysis, this paper got the results as follow:(1) In the same number of freezing-thaw cycling, c andФwill increase with the low temperature range.(2)In the same temperature range, c andФwill decrease with the increased number of freezing-thaw cycling, but will become stable with greater numbers of freezing-thaw cycling.(3) deduced the calculation formulas of three different temperature range t, three different cycling numbers, c andФ, and compared the experiment value and the formula value.(4)In the same numbers of freezing-thaw cycling, T will increase with the low temperature range.(5)In the same temperature range of freezing-thaw cycling, T will decrease with the increase of numbers of freezing-thaw cycling.