Analysis Of Dynamic Response Of Surface Building Under The Condition Of Blasting Excavation Of Urban Tunnel

With the rapid development of urban underground traffic construction, the city subway, novel underground traffic engineering such as highway tunnel and underground pedestrian streets emerged constantly. Although tunnel construction accumulated several construction methods for ages, but mining method is still the most economic and reasonable construction method in hard rock tunnel project. For many years, the mining method has been continuously improved and perfected in application, but tunnel blasting vibration effect caused by blasting excavation is still not getting good solved. Blasting excavation of new urban tunnel will affect the formation and surface ancient architecture (structures) near inevitably. Especially in dense urban area, the consequences and damage is unimaginable.In order to research the vibration velocity response law of surface construction under the conditions of city tunnel blasting excavation, the particle vibration velocity on ancient architecture has been monitored and analysised based on Kuiqi-tunnel of Fuzhou airport highway in this paper.Also, the vibration velocity response law was learn. Meanwhile, combining the actual tunnel construction condition, large dynamic finite element analysis software-ANSYS/LS-DYNA has been used for numerical simulation to check the vibration velocity response law on-site. At last, the reasonable excavated procedure applicable to this project was put forward.In this paper,the main jobs and results are as follows:①Field monitoring scheme of blasting vibration effect was determined by analysis Fuzhou airport highway tunnel engineering survey, existing common monitoring principle and method of tunnel blasting. The peak vibrating velocity and main vibration frequency of surface buildings were drawn the under the condition of tunnel blasting excavation by using field test method.②The surface buildings response law of particle peak vibrating velocity and main vibration frequency under the condition of tunnel blasting excavation was drawn by analyzing site monitoring data (particle peak vibrating velocity and main vibration frequency).③The key problems of numerical simulation method were briefly put forward such as blasting loading model, blasting load calculation, boundary and damping conditions. According to the actual situation of Kuiqi-tunnel, numerical simulation research of blasting vibration effect was done by using ANSYS/LS-DYNA software.④Through the comparative analysis between numerical simulation results and field measured data, the feasibility of numerical simulation method is interpreted in tunnel blasting vibration effect study. The surface building response law of site measured was further verified by using numerical simulation results.⑤Through the comparative analysis between peak vibrating velocity of different blasting excavation schemes, then tunnel excavation procedure was educed to guide site construction.