Research On Construction Technology Of Large Crosssection Of Chongqing North Railway Station In Complex Environment

With the accelerated process of urbanization in China, more and more cities have joined the ranks of subway construction. In recent years, a large number of large cross-section tunnels have been built in the area of the central area of the city with heavy traffic and buildings. So the research on the large cross section tunnel construction technology is imperative.The paper relies on the Chongqing North Railway Station as well as line 10 and the loop line.Based on the engineering analogy, numerical simulation and field monitoring measurement, this paper studies the construction scheme of the new station in Chongqing.1.First of all,in this study,the prediction and control of the pile displacement in the underground excavation section of Chongqing metro line 10 is carried out. By means of theoretical analysis and numerical simulation research, the control of existing structure displacement is broke up into parts, finishing the quality control from point of quantitative change and avoiding the accumulation of risk, so that the construction process is in a positive and active position.2.Using the finite element analysis software MIDAS/GTS, a numerical simulation is performed on several construction schemes of the line 10 and the loop line cross section.We compare alternatives from safety, construction period, the impact of the existing structure, the the degree of construction difficulty and so on. I summarize the programme of carryying out the excavation of the loop line and then carryying on the excavation of line 10 is the best plan.3. Line 10 and the loop line cross section is the weak part of the tunnel. I studied the application of blasting vibration reduction technology of electric blasting cap for this part.I put forward a blasting construction scheme,and then guide the blasting construction.4. By monitoring data of surface subsidence, vault subsidence,I got the change curve of surface, vault and the change regulation of the surface and vault subsidence displacement caused by the excavation of the tunnel.Comparing monitoring data and the results of numerical simulation, monitoring data and numerical simulation results are basically identical.