Research On Influencing Factors And Susceptibility Evaluation Of Salivary Ice On The Traffic Corridor Of Sichuan-tibet

Salivary ice is a kind of geological disaster widely developed in the areas along the Sichuan-Tibet Railway.Its formation is obviously affected by temperature,groundwater burial conditions,topographical and geomorphic conditions and human activities.The research of development mechanism and control factors can guide disaster prevention in engineering.Based on the analysis of field salivary ice survey data,this paper calculates the distribution of salivary ice under the conditions of altitude,slope aspect,groundwater level,topographic undulation,confluence area,overburden thickness,aquifer thickness,etc.Through Google satellites,the distribution of salivation ice punctuation in the field on the image is analyzed,and its distribution characteristics under different slope types are analyzed.Based on the analysis of statistical data,the formation mechanism of salivary ice and its distribution characteristics under various slope types are further studied through laboratory tests.The test mainly measures different freezing depths,slope types,overburden thickness,and aquifers.Under the conditions of thickness and aquifer permeability,groundwater pore water pressure and temperature data are used to analyze the changes of groundwater and freezing depth in the slope during the formation of salivary ice.Temperature changes the pressure inside the slope by affecting the formation of the frozen layer,so that groundwater seeps out to form salivary ice;the buried conditions and runoff path of groundwater will affect the formation scale and distribution position of salivary ice.Based on the experiment,numerical analysis is adopted.The software further simulates the variation of pore water pressure and velocity of groundwater under different head height,slope type,overburden thickness,aquifer thickness and aquifer permeability.Based on the in-depth analysis of the factors affecting the formation of salivary ice,six factors including altitude,slope,aspect,groundwater level,overburden thickness and aquifer thickness are selected,and the fuzzy mathematical numerical analysis method is used to quantitatively study the factors in the salivary ice.The weight of the ice formation process,the results show: according to the weight of the weight from large to small according to this is the height of the water level,altitude,overburden thickness,slope,aquifer thickness,slope direction,the weights are 0.328,0.253,0.203,0.114,0.065 and 0.037.Combining the weights of each factor to obtain the regression equation of the probability of salivation ice susceptibility,the data substitution method is used to classify the equation solutions according to the probability of survey salivation ice.The grading results are [0.216,0.430),[0.430,0.660],(0.660,0.983],the probability of occurrence of salivation ice corresponding to all levels of data is 0%,26.0%,82.5%.The accuracy of the regression equation and grading interval is verified,and the verification results show that the maximum error is 1.2%.The calculation accuracy is satisfied,and finally the slope with the y value in [0.0687,0.430] is set as the salivation ice less occurrence area,(0.430,0.660] is the salivation ice occasional area,and(0.660,0.983] is the salivation ice easy prone area.