Research On Mechanical Mechanism And Numerical Simulation In The Process Of Cavern Surrounding Rock's Excavation And Supporting

With the continuous development of the transportation infrastructure,the city subway,light rail,highway and railway tunnel construction are constantly emerging,which provides convenience for human travel.In addition,the use of coal,oil and other resources,greatly boosted the economic development of the region.The excavation and supporting practice of underground chamber has been very rich,but its theoretical research is relatively lagging.At present,the theoretical research of underground chamber surrounding rock is mainly based on after-excavation.However,in the process of high ground stress and soft rock chamber excavation,the local displacement may be too large if excavation is not completed,so that the rock will fall off or even collapse.The reasons for this are that the design and construction of countermeasures,insufficient estimation of displacement of surrounding rock during excavation.On the other hand,a lot of chamber supporting resistance by lack of field experience to support,but the lack of theoretical supporting,part of the region may be larger or the surrounding rock stress is weak,resulting in local deformation of supporting structure as well as economic losses.Based on this situation,this article on the basis of previous studies,according to the deformation characteristics of chamber excavation in the process after the peak,the predecessors of rock after excavation supporting theory,based on Mohr-Coulomb yield criterion,considering the shear characteristics of soft rock swelling,softening and space,anchoring effect,the surrounding rock from excavation to support the whole process of elastic-plastic theory,and discusses the theory of internal force of supporting structure of surrounding rock bolt and lining,the safe evaluation of supporting structure.Numerical simulation on rock excavation and supporting process by numerical software ABAQUS.Firstly,effects of surrounding rock in the excavation before,during and after the excavation of surrounding rock stress,displacement and plastic zone scope changes;and then add the bolt and lining in the process of excavation supporting and comparison of the two cases,the stress of surrounding rock the displacement and the plastic zone.Finally,on the structure of bolt and lining are simulated by the internal force of the structure simulation situation,further verify the correctness of this chapter two or three.Based on the Luling Coal Mine 1 mining area of Shimen III tunnel as an example,analysis of the excavation ? support process of elastic-plastic theory solution and compare the results with measured and numerical examples of the simulation.This paper verify the surrounding rock of the underground chamber excavation and applicability of the theory support in the process.In addition,the original scheme was improved,and shorten the excavation face support surface distance,and predicted by the stress and displacement of the improvement program from the perspective of theory.For further protect the roadway excavation and supporting process of safety,providing a theoretical basis for support design of underground chamber excavation.