Double Track Tunnel Blasting Vibration Signal Analysis And Construction Practice Of Blasting

With the rapid development of social economy, the economy of our country and the level of science and technology has make a spurt of progress of the construction progress, economic development needs of mining, water conservancy and hydropower development and various amounts of highway, railway and other infrastructure, involves a lot of tunnel excavation in these projects. On the other hand, the tunnel excavation environment becomes more and more complex, in addition to above the tunnel construction often encountered parallel tunnel. Double line tunnel blasting vibration influence on existing tunnel is large, causing damage to the adjacent existing tunnel blasting vibration of a considerable portion of the existing tunnel, which can greatly reduce the service life, so we must control the tunnel blasting vibration. This paper based on the analysis of blasting vibration signal of the existing tunnel, the key to control vibration, to ensure that the double line tunnel construction safety, this paper briefly introduces several methods of analysis of blasting vibration signal (1) fast Fu Liye transform (2) wavelet transform (3) HHT transform, HHT method is the analysis method of the suitable for blasting vibration signal tunnel. Based on the double track tunnel is a tunnel blasting vibration signal acquisition, analysis and calculation of blasting vibration velocity signal decomposed by HHT method using MATLAB numerical, empirical mode decomposition into intrinsic mode functions, to determine the feasibility of the proposed scheme of blasting vibration, blasting scheme is scientific and reliable, and guide the subsequent construction. Fresh air Ping Ling tunnel blasting excavation construction project based on the blasting excavation operation, acquisition of existing tunnel blast side and back blast side wall, floor station of blasting vibration waveform, by comparing the vibration test data and numerical simulation data analysis, found the following characteristics of tunnel blasting vibration:blast side by the explosion should the other2direction directly incident stress wave effect of radial particle velocity greater than the velocity; face blast side wall on the side for the most dangerous area, the second at the bottom of arch, the relative safety; according to the results of analysis and optimization of blasting parameters, improving the construction progress, but also to ensure the safe operation of the existing tunnel.