Research On The Design And Construction Technology Of Small-distance Tunnels On Xiaomo Highway

Recently,along with the economy developing in high-speed as well as the vehicles,the phenomenon of traffic-jam is growing more serious than ever before.People can't ignore this problem because people have a great desire to have a more efficient,convenient and faster way to go out.For the reason that the tunnel can save people's time and oil,it become more important than ever before.Building a road tunnel between two roads is a quite efficient way for nowadays but the tunnel near the other tunnel will bring effect to each other and the strain,stress and stability will be more complicated than single tunnel.Different construction method will also bring effect to these.Because of what said above,it is very necessary to do the research to reasonable distance between two tunnels and the effect brought by the different construction method and construction order to the stress,strain and stability of tunnel.Basing on Yun Nan Xiao Mo high-way Meng Yuan NO.1 tunnel,this paper used ABAQUS and theory analysis method to simulate the effect caused by new tunnel construction to the stability of the old one and to analyze the surrounding rock's changing characteristics and under different level of surrounding rock,the effect causing by the new to the old.Using benching tunnelling method and unilateral pilot tunnel method to do this research and according to the results,it reveals the different excavation method's effect to the surrounding rocks.Analyzing the reasonable distance between new tunnel and the old one.This paper has used the numerical simulation way to analyze the stress and strain of the tunnel surrounding rocks in four level of surrounding rocks and given the results of under different level surrounding rocks the effect brought by the new tunnel to the old.Based on the results,this paper chose the IV level surrounding rocks as the research project.Using benching tunnelling method and unilateral pilot tunnel method to do the numerical simulation work of the new tunnel.According to the results,a reasonable construction method is proposed.This paper combined the results of different construction method of building the new tunnel and chose different clear distance to simulate so as to analyze the interact effect with each other between the new and old.Giving the reasonable clear distance of the new tunnel under IV level surrounding rocks.