Study On Evaluation Method Of Technical Status For Highway Cutting Slope In Operation Period

Highway slope problem has a long history,and with the acceleration of highway construction has become increasingly prominent,many highways in the operation period have appeared varying degrees of slope deformation,instability damage and other phenomena,not only threatening the safety of highway traffic,but also restricting the local highway transportation efficiency.Correct and reasonable evaluation of the technical condition of the slope and appropriate maintenance measures to strengthen the safety prevention and control of the slope can not only effectively prevent the occurrence of landslides,collapses and other slope disasters,ensure the personal safety of past personnel,but also save funds for highway operation and maintenance.Because of the uncertainties in the geological structure,the boundary of stability and the quantification of the index contribution rate of the slope,the qualitative description and quantitative data are transformed into fuzzy language by the method of fuzzy comprehensive evaluation,and the mode of action of each influencing factor is omitted.On the basis of statistic of a large number of random situations of the slope and the current slope,a multilevel system is established.Fuzzy evaluation model of slope technical condition is used to judge the state of slope.Based on the statistical analysis of 35 highway landslides and 14 collapses in Chongqing area,the main factors affecting the technical condition of the slope are discussed.According to the failure mode,the slope instability law of each influencing factor(index system is composed of 4 aspects and 10 elements,including topography,meteorology,hydrology,geological environment,etc.)is analyzed,and then various failure modes are put forward.Criteria for classification of indicators.On the basis of known actual evaluation grade and evaluation index parameters of several slope samples,the evaluation model is transformed into computer language by using MATLAB software,and the weight of each index is searched globally by using genetic algorithm optimization theory.The optimal index weight which converges to the maximum extent in various failure modes is obtained,thus ensuring the objectivity of the weight.This paper uses the fuzzy comprehensive evaluation model to evaluate the technical condition of nine slopes of Shazhuang-Huadu Beixing Highway in Zengcheng,Guangzhou,and validates them with the slope monitoring system.The evaluation conclusion is in good agreement with the results of slope monitoring.It shows that the application of the fuzzy comprehensive evaluation model to the rapid preliminary evaluation of slopes has certain rationality and practicability.