Study On Disc Cutter Wear Prediction And Tunneling Parameters Optimization Based On Model Test Of 400mm Diameter Shield

In the process of tunnel construction,the shield cutters are often seriously worn,and they need to be replaced in time.However,frequent shutdown,cabin opening and cutter replacement not only bring a lot of potential safety hazards to operators,but also affect the construction progress and cost.Therefore,the research on cutter wear has important engineering value and research significance.This paper takes the hob as the research object,through the indoor model test to explore the relationship between the driving parameters and hob’s wear,establishes the hob wear prediction model,and optimizes the driving parameters to reduce the hob wear and improve the driving efficiency.The main research contents are as follows:(1)The research status of shield cutter wear at home and abroad are analysed,and the technical route is determined.Based on the existing research results,the calculation formula of cutter wear is deduced by using energy conservation theory and classical friction and wear theory.The validity of the formula is verified by the cutter wear records in construction.(2)Based on the research of shield model test and the purpose of this paper,the design scheme of tool wear test platform is proposed.According to the similarity theory,the maximum thrust of the test platform is 30000 N,and the maximum torque of the cutter head is1000N·m,which is used to guide the selection of equipment and sensors.According to the mechanical design standards for structural design,and ultimately build a test platform to meet the use requirements.(3)The hob wear test was carried out on the test platform,and the test results were analyzed from two aspects: rock breaking and wear.The concept of rock-breaking efficiency is used to analyze the rock-breaking effect of the hob and the influence of the tunneling parameters on the wear of the hob.The hob wear prediction formula was established based on the test data,the tunneling time per unit distance(100mm)was defined as the tunneling efficiency,and the tunneling parameters were optimized with the maximum tunneling efficiency per unit distance and the minimum hob wear as the optimization goals.Using genetic optimization algorithm to solve,select a set of optimized tunneling parameters to predict the service life of the hob,and guide the replacement of the test hob.(4)The rock breaking simulation of hob is carried out by ABAQUS,and the influence of cutter head speed,penetration and cutter spacing on the force and friction work of hob is studied.The simulation of hob wear by EDEM verifies the correctness of the test results and the discrete element model.