Investigation On The Anti-Blast Properties And Mechanism Of Honeycomb Steel-Tube-Confined Concrete Shield Structures

The rapidly development and application of earth penetrator in morden war promote the development of shield technology.The steel-tube-confined concrete has better anti-penetration performance than ordinary concrete.Based on the existing research of performance against penetrating and mechanism of steel-tube-confined concrete targets,the performance and mechanism against blasting of honeycomb steel-tube-confined concrete targets are studied with experiment methods,numerical simulation and engineering modeling.The mechanism against blasting of honeycomb steel-tube-confined concrete targets is revealed and a quasi-static model of deep-buried explosion to predict damage is developed.The results in this paper have important practical engineering application value.The mainly works can be summarized as follows:1.Experiments of contact,shallow buried and deep buried explosion of honeycomb steel-tube-confined concrete targets are conducted,and comparing with the agaist deep blasting performance of semi-infinite concrete targets.The influence factors of agaist blasting are studied,such as the depth and quality of explosive.The damage modes and damage parameters of targets are obtained.The results show that: The honeycomb steel-tube-confined concrete targets have the better performance to against deep buried explosion than the semi-infinite targets,and the damage modes is related to the depth of the explosive.The depth of explosive has a significant effect on the blasting crater volume and depth,but the impact of explosive quality is not significant,which has a significant impact on the maximum diameter of the blasting cavity.2.Mechanism against blasting of honeycomb steel-tube-confined concrete targets is revealed with ANSYS/LS-DYNA.The response process and the restraint effect of steel pipes of shallow and deep buried explosion are analyzed.The influence factors of agaist blasting are studied,such as the depth and quality of explosive,the thickness of steel wall and so on.The results show that: Based on the FEM-SPH method,combining the CSC model and the HJC model to describe the concrete in different response areas can better simulate the closed explosion experiments.The shallow and deep buried explosion response process can be divided into the blasting cavity formation stage,the blasting crater formation stage and the stable response stage,but there are differences in the first two stages.3.The quasi-static spherical and cylindrical blasting cavity engineering model of rock-concrete infinite medium and honeycomb steel-tube-confined concrete are established based on the theory of cavity expansion,and combining the detonation gas' s adiabatic relation before and after explosion.The Hoek-Brown criterion is used to describe the material in the comminuted region.The results show that: The quasi-static blasting cavity engineering model of rock-concrete infinite medium agrees well with the experimental results.The quasi-static spherical blasting cavity engineering model of honeycomb steel-tube-confined concrete is in good agreement with the experimental and numerical simulation results,but the quasi-static cylindrical blasting cavity engineering model of honeycomb steel-tube-confined concrete has large errors.