The Research On Deformation Control Of Shallow Tunnel Construction In Mountain

Since entering the new century,the scale of China’s infrastructure has gradually expanded,especially in recent years,the infrastructure of the southwestern region was in full swing,the southwest geological situation is complex,inevitably there will be many harsh geological conditions of highway tunnels,it is very important to study the deformation control of shallow buried section of tunnel.Therefore,combined with the Maliya Tunnel Engineering of Zhang Sang Expressway,this paper studies the construction deformation control of the shallow tunnel in the mountain tunnel,Methods like collecting data,theoretical analysis,field testing and numerical simulation is combined to probe the deformation of the surrounding rock,the numerical model was set up by the finite element software Midas GTS-NX,the influence of different construction methods on the deformation of surrounding rock is demonstrated by different depths,and the dynamic response law of tunnel blasting load is analyzed.The main contents of this paper are as follows:(1)Relying on the Maliya Tunnel Engineering of Zhang Sang Expressway,this paper introduces the stratigraphic lithology,hydrogeology and geologic structure of the tunnel area,combined with the domestic and foreign related research results,analyzed and summarized the failure types of shallow tunnel,as well as the factors affecting the deformation of surrounding rock,and the deformation mechanism of surrounding rock is also studied.(2)According to the engineering geological survey report,the rock-related rock mechanics parameters were selected,and the two-dimensional numerical model was established by using the finite element software to simulate the left line of tunnel ZK34+910,which was divided into different buried depth.The different construction methods were used to study the mechanical response of the tunnel excavation on surrounding rock deformation mechanism.(3)Considering the influence of the blasting excavation on the surrounding rock and the lining structure have been completed,the three-dimensional numerical model under different depths is established by using the Midas-GTS NX dynamic load analysis module,the stress and displacement of the surrounding rock and the supporting structure of the tunnel are analyzed,so as well the peak vibration velocity of the initial support.The research work provided in this paper provides the theoretical basis for the safe construction of the Maliya tunnel and other similar underground constructions and also offers the designing and constructing experience for the tunnel engineering under the similar geographic conditions.