Deformation Uniformity Research Of Double-plat Cutterhead Of Full-face Rock Tunneling Boring Machine

Full-face Rock Tunneling Boring Machine(TBM)is widely used in tunneling projects because of its advantages of high efficiency,economy and safety.The cutter disc is the core component of the machine,and its performance is directly related to the tunneling efficiency.When tunneling and breaking rock,the cutter disc is subjected to complex forces,and the cutter disc produces deformation,vibration and even fracture.Therefore,the design of cutter structure parameters and the improvement of cutterhead deformation uniformity have been the key research problems of TBM.This paper takes the double-plate cutterhead as the research object,and studies the influence of cutterhead structure parameters on its deformation uniformity under different load conditions,the key risk position of the cutterhead under load and the design of cutter structure parameters.The paper also compares and analyzes whether the best cutter is replaceable under different loads,and improves the uniformity of cutter deformation by changing the size of the hob on the cutter,which provides a reference for the design of cutterhead structure parameters and deformation research of full-face rock tunneling boring machine.The main contents of this paper are summarized as follows:(1)Summarizes the evolutionary development of the cutterhead structure of full-face rock tunnel boring machine and the current status of research related to hob and cutter;describes the main structure,working principle and classification of full-face rock tunneling boring machine;introduces the relevant structure of cutterhead system and determines the actual loaded position of cutterhead.(2)Analyze the load theory of rock-breaking of disc-shaped hob,determine the calculation of external load on the cutter,and make relevant inductive derivation of the bending deformation theory and support stiffness theory of the cutter of TBM.By establishing the rock breaking model of the hob and conducting finite element simulation of the force on the hob under actual working conditions,the load characteristics of the hob are analyzed and the magnitude of the external load on the cutterhead is determined.(3)The study based on the theoretical state of the cutter disc loaded as under uniform load.The three-dimensional solid modeling of the double-plate cutterhead,and the orthogonal test design and simulation are used to study the design of the parameters of the thickness of the front plate,the thickness of the rear plate,the distance between the two plates and the diameter ratio of the supporting plate of the cutter,as well as the order of influence on the uniformity of the deformation of the cutter.The structural parameters of the cutter disc are further determined by the control variable method,so that the structural design of the cutter disc can be further optimized.(4)Based on the study of the actual cutter hob seat under concentrated load.In order to contrast with the study of uniform load,the research methods and steps are consistent with the study under uniform load,and the optimal parameter design of the cutterhead structure under concentrated load and the order of influence of each parameter on its deformation uniformity are obtained.By studying and analyzing the deformation of the cutter disc subjected to different loads,the location of the dangerous deformation structure of the cutter disc is obtained.(5)Based on the different load forms of double-plate cutterhead,analyze whether the resulting cutterhead is replaceable when subjected to different loads;compare and analyze the parameters of cutterhead deformation uniformity index by changing the size of hobs in the inner and outer domains of double-plate cutterhead,and study the influence of different sizes of hobs installed on the cutterhead on its deformation uniformity.