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Mechanical behaviors of pile-soil effect and anchor-soil effect are significantly important in supporting engineering activities of foundation pit. In this paper, finite difference method (FDM) was utilized to perform the numerical simulation of pile-anchor system, composed of supporting piles and pre-stressed anchor cables. Numerical simulations were on the basis of the foundation pit of Jinan's West Railway Station, and 3D simulation analysis of foundation pit has been prepared during the whole processes of excavation, supporting and construction. The paper also analyzed the changes of bending moments of piles and axial forces of cables, and discussed mechanical behaviors of pile-anchor system, through comparisons with field monitoring. The results show that the parameters concluding vertical gridding's number, cohesion of pile and soil, and pile stiffness have robust influences on supporting elements' behaviors. Mechanical behaviors of supporting pile and axial forces of anchor cable changed dramatically, indicating that the potential failure form was converted from toppling failure to sliding failure., 4th International Conference on Civil Engineering, Architecture and Building Materials, CEABM 2014; Haikou; China; 24 May 2014 through 25 May 2014, Applied Mechanics and Materials, 580-583, pp.238-242; 2014

International audience; A passive twist control is considered as an adaptive way to maximize the overall efficiency of a proprotor developed for convertible Micro Air Vehicles (MAV). In this paper, adaptation of the proprotor geometry in accordance to flight configurations is achieved by induced twist generated by the inherent structural coupling effect in anisotropic composite material and centrifugal force emanating from the tip load. Beam Finite Element Model based on Rotating Timoshenko Theory is used to predict structural loads, while Blade Element Momentum Theory is employed to predict the aerodynamic performance of adaptive proprotor as applied on Micro Air Vehicles (MAV). The iterative process of combination of aerodynamic model and structural model is used to compute the steady-state deformation of the flexible laminated proprotor blade due aerodynamic loads. Finally, the optimal design of lamina blade material is carried out to investigate the potential of flexible blade in the proprotorperformance enhancement.

To evaluate quantitatively the performance of cushioning materials, a cushion curve is indispensable. However, the desired cushioning effect may sometimes be absent when we use the cushion curve to design a transport package. In addition, to plot the cushion curve, massive dynamic compression tests are traditionally necessary. Thus, large amounts of labor and material resources are required. Therefore, we used expanded polyethylene and laminated-board cushion as test materials to represent typical cushioning materials, and proposed simplified performance evaluation methods based on certain dynamic compression tests. An analysis of the experimental results showed that to obtain a more accurate packaging design, the shearing effect must be taken into account when using the cushion curve; For both plastic and paper cushions, new proposed performance evaluation methods significantly reduce the number of dynamic compression tests needed to accurately evaluate an actual packaging design.