Research On The Effects Caused By The Construction Of The Qinyun Square And The Controlling Technology Of The Nearby Existing Railway Tunnels

The highway and railway transportation are developed rapidly in the 30 Years of Reform and Opening. Especially in recent years, as the rapid development of the economy, the network of the road is improved constantly. Then existing structures will be rebuilt around the new structures because of some Engineering phenomena, the expansion of the existing tunnel line, for example.Based on the construction of Xiaolongkan tunnel which is constructed around the Qinyun square, we do numerical simulation on the excavation of the square and the construction of peg foundation by the finite element analysis software. Then some reinforcement measures are given to the diseases of the existing tunnels. The results are shown as follows:1,In the approaching construction of the tunnels, the key problem is to find out the effects on the existing tunnels that caused by the new projects or by themselves. During the construction, how to decrease the influence is the core problem. Nowadays, the research method of the adjacent construction is divided into three kinds:theoretical study, experimental study, and numerical simulation study.2,Redistribution of stress is caused by the movement of the ground, so it'll have bad effects on the existing structures nearby. However, because of the difference between the structures, the corresponding indicators are also different. There's a relation between tunnels, ground and the existing structures, so we shouldn't ignore the relationship between them.3,We do safety evaluation on the existing railway tunnels by the numerical simulation method. It's concluded that the structure is relatively safe when there are no other disturbances or loads.4,During the construction of the Qinyun square, we can conclude that in the three conditions tensile stress are shown. Obviously it will cause bad effects on the lining structures for the lining structure is masonry structure.5,According to the existing domestic and foreign reinforcement technology, some advanced reinforcements are done in order to prevent engineering diseases. Good results are achieved.