Papers by Keyword: Falling

Abstract: In the paper, the monolithic design of cushion package for airdrop system is summarized. In the meantime, the author improves the former package in the foundation of entire recognizing and introduction of the former research. The airdrop package not only effectively overcomes the wallop of ground, but also prevents the rebounding and side rolling when the system fall into the ground, which really has an effect on the airdrop system.

Abstract: The annual occurrence of hip fracture increases very rapidly, which cause a heavy public health burden. From a biomechanical perspective, hip fractures are thought to be caused by different directions of load. Fifteen different load conditions were studied here to simulate various falling configurations, the directions of which were defined by angle γ, δ. The purpose of the current study was to clarify the influence of load direction on strength and fracture site of the proximal femur using FE method to determine the load direction under which the proximal femur is most vulnerable to fracture.

Abstract: In this paper, the process of failure and falling of the rock masses in the underground mining is studied; and the relationship between the processes of failure and falling of rock masses is proposed based on the rockmass strength theory. Research indicates that the failures of the rock and rock masses are probably not at all in common. Even though the rock masses go into the plastic condition, even to the extent that come into being in the failure, they do not surely fall. Hence, the mechanical properties of rock mass, especially after the failure, still need to be further researched. The laneway and the stope in the mining engineering are the temporary engineering, the load- carrying ability of the rock masses should be bought into play as far as possible, and therefore the stabilization during failure process is a significant for the supporting in the underground mine under safety prerequisite. Since 1 million m3 of the mined-out area is formed by mine for many year at Xishimen iron mine in China, and the gob roof is only 54m from the ground, the mined-out area is potentially dangerous to the underground mine. This paper analyzes the pattern of the stability and falling process in the mined-out area based on the theoretical analysis and numerical calculation, in order to obtains the falling criterion of the roof rock masses and stabilize the mined-out area. The predicted falling shape and range of the mined-out area is compared well with the in-situ observations. This contribution has also been popularized in many mines of China.