Analysis Of Blasting Test And Collapsing Touchdown Vibration Response

With the rapid speed of economic development and urbanization progresses, a large number of buildings, structures and bridges are faced with the problem of demolition. Demolition is divided into mechanical removal and blasting, this paper analyses the effect of the blasting vibration and vibration touchdown collapse and judge which one could cause greater impact. By the result of test and numerical analysis this paper acquire the conclusion that touchdown collapse vibration could cause greater impact, at the same time this paper make a comprehensive analysis of factors of the touchdown collapse vibration response. The final research results are applied to the numerical simulation of Zhuang Yang viaduct blasting project.Firstly, this paper uses fluid-structure coupling method to simulate the single-column blasting vibration test, the simulation of blasting vibration considering the surrounding environment. The final numerical results are in good agreement with experimental results and prove that the numerical simulation method is feasible and effective, it can be applied to similar projects and experiments.Secondly, this paper simulates the blasting collapse touchdown test, the simulation considers the impact of the touchdown vibration to the surrounding environment. The final numerical results are in good agreement with experimental results and prove that the numerical simulation method is feasible and effective, it can be applied to similar projects and experiments.Through a single column collapse touchdown burst test and vibration test, this paper concludes that touchdown vibration has a bigger impact. At the same time the related simulation verifies this conclusion, in the actual bridge blasting engineering could only consider touchdown collapse vibration process.This paper argues that the collapse touchdown vibrations have a greater impact and makes a detailed analysis of the factors of touchdown vibration response, these factors include a buffer layer, a green belt and trench isolation. If there are no treatment in actual blasting, the touchdown vibration have a great response; if there are a buffer layer, a green belt or trench isolation, the response would be smaller. Especially in the presence of isolation trench, the response of touchdown vibration would be the smallest.The conclusion is that the touchdown vibration is the main process in the actual bridge blasting. On the basis of the conclusion I set up the numerical model and consider all aspects of the factors, such as the rubber buffer layer, the soil green belt and the specific monitoring location. In the end, the process of the bridge blasting is simulated by the finite element analysis software successfully.This paper conclude that the touchdown vibration cause greater speed and acceleration than the blasting vibration. On the other hand, this paper makes the simulation of the blasting demolition and the slump touchdown vibration successfully.