Study On Mechanism Of Hob Eccentric Grinding And Mudstone Argillation During Hob Rock Breaking Process

With the rapid development of subway projects in China,TBM has been widely used in tunneling.The working principle of TBM is that the cutter disc contacts with the rock and rotates to break the rock under the action of thrust and torque.In this process,a lot of heat is generated by the friction between the cutter and the rock.Hob temperature has an important influence on the mechanism of hob rock breaking and the wear of hob itself.Especially in the condition of broken soft rock,the dual action of temperature and water makes the rock breaking of hob more complicated.Therefore,in order to study the micro mechanism of hob breaking soft rock under the action of temperature and water,this paper adopted a new scale hob cutting model,and analyzed the mudstone and hob after the experiment by thermal imaging technology and microscopic imaging technology.The main contents are as follows:Firstly,through a new hob cutting rock breaking platform and real-time monitoring of hob surface temperature in the process of hob rock breaking with thermal imaging equipment,the temperature change rule of hob broken mudstone and hard rock was studied.And the influence of lithology on the hob temperature change trend was analyzed.In addition,the microscopic wear mechanism of the hob surface under different rock crushing conditions was investigated by using microscopic imaging technology.The relation between rock breaking temperature and hob wear was established.Secondly,The influence of hob temperature on the microcosmic mechanism of broken mudstone was studied,and the influence of hob temperature on rock breaking efficiency and hob wear was analyzed.The effects of different moisture content of mudstone on the microscopic mechanism of hob and hob crushing mudstone were studied.The mechanism of hydrothermal interaction in the process of high temperature hob crushing high moisture content mudstone was studied.By applying statistical methods,the severity of partial wear in high water content hob crushing was evaluated.Finally,The effect of thermo-mechanical coupling on hob rock-breaking efficiency was studied.In addition,the energy of each component in hob rock-breaking was analyzed from microcosmic and macroscopic perspectives.Compared with the traditional CSM model,the effect of thermal-mechanical coupling on the rock breaking efficiency of hob was studied.