This paper describes the research status of MEMS spring used in fuze. For the Nickel planar S-form micro-spring, according to its application environment and design requirements, the length of the straight beam was taken as the only variable to study the variation of the micro-spring dynamic stiffness under high impact load. These researches can provide some reference views to design applications and reliability analysis of micro-spring used in the munitions, and also can lay the foundation for the response characteristics of the micro-scale elastic components under impact load.

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In recent decades, high-tech electrical equipment has drastically proliferated instead of Cathode Ray Tube (CRT), making CRT funnel glass potential hazardous solid waste. Due to a relatively high level of lead, CRT funnel glass could be used as a potential material for the production of anti-radioactive concrete. In our study the CRT funnel glass , which was separated as aggregate in the concrete, was reduced to 4.75-25 mm (coarse aggregates) and less 4.75 mm (fine aggregates) in the production of anti-radioactive concrete. Mixes containing 0%, 20%, 40% , 60%, 80% and 100% (volume percentage) of CRT funnel glass to replace fine aggregate and coarse aggregate (respectively or simultaneously)) were prepared. The influence of the size, shape and replacement percentage of aggregates on workability, compressive strength and radiation shielding performance were determined. It was found that the replacement of natural aggregate with recycled CRT glass considerably improved the slump and radiation shielding performance but reduced compressive strength. The optimum percentage of waste funnel glass used as fine aggregate and coarse aggregate was 40%. The results clearly showed that the CRT funnel glass performed a significant enhancement in radiation shielding properties.

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With elastic theory and approximate calculation, the dynamic responses of elastic thin plates with four edges simply supported under blast loading is analyzed in this paper , with dimensional analysis , 30 cases are calculated, and a reasonable model of engineering calculation is built up in the end.

The variation process of radius and pressure of explosion products in borehole are analyzed in this paper, based on theory of damage and structural mechanics, the formative mechanism of blasting crater in reinforced concrete under internal blast loading is analyzed, the computation method of crater size has been proposed. The calculated results are identical with experimental results on the whole.

This article studies the changing law of the driving torque of the screw conveyor during the emptying process of the earth pressure balance shield chamber. First, the discrete element method of discrete medium theory and 3D software SolidWorks were used to create the research object and the screw conveyor model, and then the model parameters were determined and calibrated through numerical calculations and indoor experiments. The final numerical calculation results show that: 1) the screw torque will drop in waves with the increase of the calculation time. When the screw conveyor rotates at 360 deg/s, the calculated screw torque fluctuation amplitude is small; 2) when the number of particles in the soil bin is reduced to a certain extent, the use of a higher screw speed to improve the “dumping soil effect” is of little significance; 3) the negative exponential function can be used to better fit the decrease of screw torque with time; 4) for the bulk medium, for a given particle size and screw structure, there is a suitable speed, so that the effect of “machine-soil collision” is small, and the torque change of the screw is relatively stable.