Study On The Stress Of Utility Tunnel System Combined With Inclined Support

Compared with the tunnel,the most important feature of the utility tunnel is the shallower buried depth.At present,the research on the utility tunnel is mainly based on the tunnel,and there is no targeted design for the most important feature of the shallower buried depth of the utility tunnel.The section form of the utility tunnel is the same as that of the tunnel,which is round or square,but there is little research on other sections of the utility tunnel.However,it is difficult to balance the stress and deformation of the circular and rectangular section utility tunnel,and the combination of the support form and the main body of the utility tunnel is not considered.In this paper,a new hexagonal utility tunnel system combined with inclined support is proposed.Through the combination of model test and numerical simulation,the lateral stiffness efficiency and moment correction coefficient of the utility tunnel are studied,and the deformation and stress of the utility tunnel under static and dynamic conditions are analyzed.The main contents are as follows:A model test is designed for staggered joint assembly,through joint assembly and integrated ring centralized loading.Due to the complexity of the model,3D printer is used to make the model.Through the model test,the deformation characteristics of hexagonal utility tunnel in four directions under the concentrated loading mode are obtained.In addition,the effective efficiency of transverse stiffness of staggered joint assembly and through joint assembly,and the moment correction of each joint of staggered joint assembly are also given.FLAC 3D software is used to simulate the test conditions.The deformation and internal force of through joint assembly,staggered joint assembly and complete ring under online loading mode are obtained.The effective efficiency of transverse stiffness and the moment correction coefficient of staggered joint assembly and through joint assembly are calculated.By comparing the numerical simulation results with the experimental results,it is found that the two are in good agreement,which verifies the correctness of the numerical simulation.Limited to the cost,this paper uses FLAC 3D software to simulate the deformation characteristics and internal forces of through joint assembly,staggered joint assembly and complete ring utility tunnel in the soil.And the effective efficiency of lateral stiffness in the real loading mode is higher than that in the concentrated mode.This is due to the hoop effect of soil around the utility tunnel.And the law of the moment correction coefficient determines the size of the adjacent ring moment under the staggered joint assembly mode.Numerical simulation is used to study the bending moment and deformation mode of hexagon utility tunnel under three working conditions.The moment of utility tunnel considering excavation effect is larger than that without excavation effect.The inclined pile has a limited effect on the deformation of the utility tunnel.