Blast-induced Vibration Characteristics And Numerical Simulation Research Considering Blasting Source Factors

The construction progress of large-scale infrastructure and mining engineering are accelerated as the result of blasting technology application. Blasting construction can improve the efficiency of construction and create a lot of economic benefits. Meanwhile, it also brought many negative effects. In recent years blasting vibration which is the first explosion hazard, attracted more and more attention. While, blasting vibration research which affected by various factors has always be the emphasis and difficulty in the study of engineering blasting. Blasting source factors are controllable among the many influence factors of blasting vibration. Therefore, the research for blasting vibration characteristics with different source factors is also an important part of the blasting safety control.The calculation method for blasting source equivalent load is obtained based on the theoretical analysis of blasting source. On this basis, the theoretical analysis and numerical simulation methods are used to research the vibration characteristics of millisecond blasting and cylindrical charge blasting. Besides, the modified peak particle velocity(PPV) calculation formula of cylindrical blasting vibration is also proposed, based on the common used PPV calculation formula. The main results are as follows:(1) The elastic-plastic governing equation near the blasting source is established, and the specific function is introduced to transform the non-homogeneous equation into homogeneous equation. The elastic-plastic stress field approximation solution near blasting source is obtained by using Laplace transform, and then the simple blasting source equivalent load formula is obtained.(2) The millisecond blasting vibration characteristics are analyzed, and the generating mechanism of local amplification phenomenon for millisecond blasting vibration amplitude is also illuminated. The relationship between millisecond time and amplitude amplification is obtained(3) The cylindrical blasting vibration characteristics are analyzed. The influence of charge length and detonation velocity on blasting vibration amplitude is also discussed.(4) Based on the vibration characteristics study of cylindrical blasting, the modified blasting vibration PPV calculation formula is proposed by introducing the charge length influence coefficient. This calculation formula can well performance cylindrical characteristics.These research results have a certain theoretical and engineering value for blasting vibration prediction and construction.