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A selective reduced integration 8-node hexahedral element for coining simulation is developed in this paper. The element is free of volume locking by assumed strain method. The standard velocity gradient matrix is derived in which the shear items are ignored to avoid shear locking. Hourglass modes are successfully suppressed without user-input parameters. The element is successfully employed in the coining simulation package - COINFORM. Numerical tests and experiments of a typical coin are carried out to show the good performances of the element.

The paper proposed a new reinforcement technique-planting steel technique. By numerical simulation analysis of planting steel, the load – slip curve, the load – stress curve and others were obtained. Meanwhile, ultimate bearing capacity of angle was calculated, and the ultimate bearing capacities with the same model at different anchorage depths were compared. With the anchorage depth increased, the ultimate bearing capacity increased too. But while the anchorage depth increased to a certain value, the ultimate bearing capacity no longer increased. All these provided a theoretical basis for the engineering application of planting steel technique.

This paper is to make an elastic dynamic time history analysis on a steel-concrete composite structure under the effect of frequent earthquake. And it reveals the collaborative performance of steel frame and RC frame under the seismic motion effect by studying time history response of the parameters like base shear, base bending moment, structure top acceleration and displacement of the structures under the seismic motion effect. The results show that for the steel-concrete composite frame structure under the seismic motion effect, its maximum base shear, maximum bending moment, structure maximum top acceleration and maximum displacement do not occur at the same time, and dynamic response of the top steel frame acceleration, displacement and other parameters increase more significantly than the lower RC frame, while Steel-concrete composite structure may produce resonant phenomenon with earthquake vibration.

In the third generation PWR, passive containment cooling system was one of the key security parts. If accident happened, the blasting valves in the containment would automatically open and the steam would be injected into the containment. When the pressure reached a certain value, the tank on the top of containment would automatically spray. Driven by gravity, the cooling water would flow along outer surface of containment. Steam inside the containment would condense on inner wall and the pressure in the containment would decrease. A numerical simulation of steam jet in the passive containment cooling system was carried out using computational fluid dynamics methods. Flow mechanism in the process was studied. A simplified three-dimensional model of the passive containment cooling system was built. The hexahedral structured mesh was made. The RNG k-epsilon turbulence model was used in solving the transient Reynolds Navier-Stokes equations by the Fluent. The distributions of velocity in containment at different time were acquired. Reference would be provided for understanding of flow mechanism of gas jet-flow in containment during the early stage of accident.