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In a Fourdrinier paper machine, the fiber and water mixture flows to a wire-screen belt. As the wire-screen belt travels horizontally, water is drained through the screen, leaving the fibers on top. In some operating conditions large vertical vibrations of the wire-screen belt occur. The mechanism of this phenomenon is investigated experimentally. Analytical study is also done, which shows qualitative agreement with the experiment results. Consequently, the screen vibration is self-excited vibration due to the pressure variation of the water on the wire screen belt.

In the method of earthquake reinforcement on the girder bridge, there are reinforced concrete lining method and steel sheet lining method of bending proof stress control type and reinforced concrete lining method using together with steel sheet. If the girder bridge is reinforced using these construction methods, the toughness of a pier stud section in the girder bridge improves, and a proof stress of it improves, too. However, the load that the pier foundation should bear increases. In this paper, we clarify it about earthquake resistance performance of the girder bridge reinforced in pipe arches. At first, we compare a vibration characteristic found by eigenvalue analysis with a vibration characteristic provided from a vibration experiment. At second, we examine the influence that the pipe arches reinforcement gives to earthquake resistance performance from a result provided by non-linear earthquake response analysis.

Dynamic characteristics as natural frequencies and modal damping ratios of laminated composite materials are influenced by the fiber orientations and the stacking sequence. Since the transfer functions of laminated composite structures are determined by these characteristics, we pay attention to the relations between the fiber orientations (including the stacking sequence) and transfer functions in order to minimize the vibrational response of structures. This paper presents an optimum design method of laminated composite structures to minimize the vibrational response. The optimization program evaluates the frequency response functions as an objective function of the genetic algorithm. With this evaluate function, the proposed method can minimize the vibrational response against the various vibrational forces in any frequency domains. As numerical examples, the proposed method is applied to the design of a rectangular plate and a cylindrical cantilever of CFRP.

The speed-up on railway tends to require higher powered and heavier locomotives, thus two three-axle trucks or three two-axle ones are needed for the heavy locomotive to meet the limitation to axle load. Here, it is beneficial for heavy locomotives to employ forced steering trucks to reduce the lateral force between the wheel and rail during curve negotiation. This paper deals with numerical analysis about curving behaivor and running stability of the forced steering three-axle trucks. In the analysis, wheel lateral forces and the critical speed for stable running are examined parametrically varying leverage ratio and stiffness in the steering link, wheel tread conicity and wheelset supporting stiffness. In addition, the possibility for improving the critical speed is investigated. The results show that the proper value for the leverage ratio changes with curve radius, and that higher leverage ratio can make the running stability worse under large steering link stiffness. It is also shown that the proper tuning of the wheelset supporting stiffness increases the critical speed keeping the lower lateral force brought by the forced steering mechanism.

Elastic parameters are essentia for structural analysis. The elastic parameters of laminated composite materials, however, are difficult to determine by either theoretical or experimental approaches because of their anisotropy. This paper presents an inverse anaysis method to identify anisotropic parameters of laminated composite materials using FEM eigenvalue analysis. A shell element model is formulated for unsymmetrically laminated composites. The modal assurance criterion, MAC, is adopted to compare analyzed vibration modes with observed modes, because the order of vibration modes of anisotropic materials changes according to the ratio of elasticity E_L/E_T. As numerical examples, elastic Parameters of single-and multilayered composite plates are identified.

For a heavy haul railway vehicle negotiating tight curves in a factory yard, it is beneficial to employ forced steering trucks to reduce the lateral force between the wheel and rail. The forced steering truck has a wheelset supporting mechanism composed of hanging links and compressing ones for easy steering. The truck should also have a short wheelbase to meet special requirements in the yard. This paper deals with numerical analysis of dynamic behavior of the forced steering truck, in which running stability and the lateral force are examined, considering the wheelbase, the running speed, the longitudinal stiffness caused by the link mechanism, steering link stiffness and the leverage ratio. Results show that it is disadvantageous for both the running stability and the curving behavior to use a short wheelbase, and that the decrease of the steering link stiffness and the increase of the running speed also have disadvantageous effects on the curving performance. It is important for trade-off between the running stability and the curving behavior to select proper values for the longitudinal stiffness of the link mechanism and the leverage ratio.

This paper presents an efficient FEM eigenvalue analysis technique for symmetrically laminated composite plates by using a personal computer. In order to realize the analysis on a personal computer, a 12 d. o. f. ACM element considering the anisotropic behavior of symmetrically laminated composite is formulated and a subspace iteration algorithm is used for the analysis. A shaking test using CFRP symmetrically laminated composite plates is performed to prove the effectiveness of the method. It has been shown from the study that the proposed technique could be of practical use for plates with a wide variety of fiber angle and dynamic coupling between bending and torsion.