Variable Depth Explosion Numerical Simulation Of Stress Wave Propagation In Concrete

Peace and development remain the themes of the current international social development, but there are situations in breaking people’s peaceful life, such as violent and terrorist activities, accidental explosion, natural disaster, or even local wars. Every year the events people do not want to see, not only threaten all mankind life and wealth security severely, but also have a great impact on the infrastructure that facilitate human activities, and all kinds of large-scale engineering. Concrete which is one of the most commonly used base materials in engineering structure, whether it is used in the building on the ground, or in the underground space, it will become the object which is destroyed in the explosion, and that the different size and position of charge can also make great different explosive damages. This paper that is based on the analysis of the relevant basic theory of explosion in concrete, use LS-DYNA software to carry out numberical simulation on explosive stress wave propagation of different buried depth in C30concrete, and also on the C50, C70two kinds of different strength concrete in half buried, the main research contents and results are as follows:(1)By analysising the background and significance of the different depth explosion in concrete, find out the starting point and the point of innovation, and according to the design ideas of the research, has carried on the analysis to situations which are related in solving problem process, and related basic theorys.(2)The numerical calculation results show that, numerical variation of explosion field stress peaks in different buried depth condition are accordance with the experimental results, explain the calculation program and the related parameters are reasonable and feasible, prove the calculation results right.(3)From the stress and acceleration peak attenuation curves of different depth explosive in concrete can be seen: the attenuation of stress and acceleration has an exponential relationship, by fitting the decay curve, the decay index of peak stress are between1.4and1.9, the decay index of peak acceleration are between2.0and2.4.(4)Through the numerical simulation can get the critical proportion depth1.0m/kg1/3that concrete appears closed explosion, when the ratio of depth greater than this value, coupling to the underground energy will not change.(5)The numerical results show that, the propagations of stress wave are basically the same among3kinds of different strength concrete in the semi buried depth explosion, and with the increase of the strength of the material, energy which coupling to the underground increases, the stress peak’s attenuation index smaller.