The Tunnel Support Structure Optimization Analysis In Considering Parameter Value Uncertainties

Fuzziness and randomness of tunnel surrounding rock parameters is a complex and closely related to the actual engineering problem,therefore,necessary to study the characteristics of tunnel surrounding parameter values on the basis of indoor and outdoor experiments,and then will take the rock parameters value of the property is converted to values characteristic of rock parameters for the study of different parameters on the tunnel depth and rock stress and deformation of the supporting structure of tunnel foundation.This article first investigate shear strength parameters of rock analysis methods,according to the existing seven kinds of research methods and shearing strength of the principle of the four groups in FORTRAN software direct shear test data to be programmed calculated the most probable shear value interval or strength parameters of shear strength parameters.Hoek-Brown criterion combined with the empirical formula of Geological Strength Index(GSI)was constructed based on the uncertainty of the parameters of rock mass range.Secondly,this paper constructs a three-dimensional tunnel model by ANSYS software,the use of "virtual support force exerted gradual release method" to simulate various process steps down the tunnel construction method in rock stress release,analyzed the construction method of tunnel and down stairs various stages of stress and deformation characteristics.Again,depending on the level of rock surrounding rock group select multiple parameters and multiple sets of tunnel depth h substituted into ANSYS software in accordance with the results of orthogonal experiment,record levels at various stages of excavation on both sides of the dome observation points and observation points and vertical displacement,bolt stress,initial observation point lining horizontal stress and vertical stress,horizontal stress and vertical stress liner lining two observation points.And to explore the tunnel depth and rock deformation modulus of the tunnel excavation and support structures bearing influence of deformation.Then,the results were fitted using MATLAB software,to get around the convergence of functions and features performance function on vault sinking,and then take the other values of the function function checking its suitability.Analysis at different depths,the elastic modulus of surrounding rock displacement and vertical displacement varying levels of each excavation stage dome observation points and observation points on both sides,the bolt stress,the stress level at the beginning of the observation point and vertical lining stress,and trends affecting the level of stress and the vertical stress liner lining two observation points.Finally,a big dragon Yong-speed tunnel Creek I,for the study,analysis of tunnel excavation in various stages of construction by force and deformation characteristics,see Bolt meets early lining,requires two liner carrying capacity.Performance function will use this project example,to verify the applicability of the actual performance function of complex situations.