Wear A Large Building Technical Measures Of Tunnel And Risk Control

Nowadays cities are impossibly crowded in China with the accelerated urbanization process and the increase in population density. To relieve the traffic congestion, urban rail transportation has entered the fast period in major cities in China. The technique of building subway in the soft strata has become mature which is used in many cities such as Beijing, Shanghai and Shenzhen. While, the application of blasting operation to build the subway in the hard the rock strata, which may cause blasting vibration, has a great influence and harmfulness on the surrounding constructions. In the thesis, how to protect the surrounding buildings and underground pipelines by controlling the rate of blasting vibration is analyzed systematically, which is carried out by field trial, theoretical analysis and monitoring blasting vibration rate. And all the technical analysis here is based on the construction of102tender of Line one of Dalian Metro, which section goes closely under Sheng Li Shopping Gallery and several sewage culverts, in which section the interval crossover forms are changeable, so the construction methods have to be frequently adapted, which also has a very requirement to the blasting vibration velocity and the control of the ground surface settlement. The research carried out in the thesis is as following.Firstly, it analyzes that if the shaft deep foundation pit is very close to the large buildings, how to choose the blasting excavation methods, and what measures can be taken to control blasting, optimizing blasting parameter. Here the method of full face blasting forming is proposed, which not only can ensure the construction safety, but also can effectively accelerate the construction schedule.Secondly, it is posed here that when the regional tunnel is near the large underground structures, sewage culverts or other risky places, it is necessary to take the corresponding damping blasting technology, by making with large aperture damping hole arch in tunnel, taking the advantages of its cutting, barrier, the buffering effect to effectively achieve the purpose of reducing blasting vibration velocity.Thirdly, it provides with the construction technology and control measures when dealing with the interval tunnel large section line, analyzes the excavation method of construction section applicable to various kinds of frequent switching, and the measures taken to do with the maximum cross section of asymmetric double arch.Last, it formulates emergency rescue plans. As to the possible surface subsidence, pipeline leakage, cuts in electricity and water supplies, collapse of buildings and roof-falling, corresponding treatment measures are proposed, to strengthen field exercises and ensure the safety of construction.