作者: Sun Bae Kim, Ji Hwan Kim

摘要: In this study, thermal post-buckling characteristics of functionally graded (FG) panels in
hypersonic airflows are investigated. The volume fraction and the material properties of FGMs are
continuously changed from ceramic to metal in the thickness direction agreeably to a simple power
law distribution and a linear rule of mixture, respectively. Using the principle of virtual work, the
governing equations are derived and the finite element method is applied to obtain the solutions.
Based on the first-order shear deformation theory (FSDT), the FG panels are modeled by the von
Karman strain-displacement relation for the structural non-linearity. Also, the third-order piston
theory is employed to consider the aerodynamic non-linearity.

387

作者: Hong Pu Liu, Xiao Jing Li, Di Wang, Jian Sheng Tang, Xue Ling Yang, Cheng Jun Zhu

摘要: The elastic buckling load is physically important in design of the pressure vessel with shell framework because it is actually the critical step in a thin-walled shell configuration that will eventually lead to complete failure. An finite element model of vacuum autoclave was established and the buckling load calculations under the extreme operating conditons have been carried out to obtain the modal deformation condition and the safety factor. The results showed that the structure has a higher safety factor, which indicated that the vacuum autoclave design can meet the working conditon requirements.

888

作者: Zainudin A. Rasid, Ayob Amran, Rizal Zahari, Faizal Mustapha, D.L. Majid, Renuganth Varatharajoo

摘要: Thermal buckling and thermal post-buckling behaviours of laminated composite plates are improved by embedding shape memory alloy wires within laminates of composite plates. The procedure is to use the recovery stress that is induced when the reverse transformation of the shape memory alloy from martensite to austenite phases is constrained. For aerospace applications where the source of the shape memory alloy heating is the high temperature environment itself, a study is conducted to see the effect of shape memory alloy in improving the thermal buckling and post-buckling of composite plates. Due to the temperature dependent nature of the composite matrix and the shape memory alloy, the finite element formulation developed here is in the incremental form. Solving this non-linear model using the developed in-house source code, critical loads are determined and the post-buckling paths of the shape memory alloy composite plates are traced. This study shows that by embedding the shape memory alloy within composite plates, the thermal buckling and post-buckling behaviours of composite plates can be improved substantially.

536

作者: Saeid Rasouli Jazi, Fatemeh Farhatnia

摘要: In this paper, buckling analysis of functionally graded super-elliptical plates is investigated by pb-2 Ritz method. The governing equation is derived based on classical plate theory (CLP). Since closed form solution of buckling differential equation is not available under various boundary conditions, pb-2 Ritz method (energy method) is applied to calculate non-dimensional buckling load. Total potential energy is given as summation of strain energy and work done by applied in-plane compression load. In order to obtain the buckling load, pb-2 Ritz method is applied corresponding to different peripheral supports (Clamped and Simply Supported) are used in the present study. The plates are assumed to have isotropic, two-constituent material distribution through the thickness and the modulus of elasticity of the plate is assumed to vary according to a power-law distribution in terms of the volume fractions of the constituents. Variation of buckling non-dimensional parameter is considered with respect to various powers of super–elliptic, FGM power law index and aspect ratio.

5387

作者: Hou Jun Kang, Yue Yu Zhao, Hai Ping Zhu

摘要: Cable-arch structure is a combined structure, which utilizes flexibility of cable and rigidity of arch. Cable-arch structure has been widely used in bridge engineering. In this work, we proposed a novel mechanical model of cable-arch structure. The out-of-plane buckling and in-plane buckling were studied using the energy method. The formula of critical loads of both the first order out-of-plane buckling and in-plane buckling were derived using Rayleigh-Ritz method. An example is ultimately investigated numerically. The results indicate that the cable can improve considerably the out-of-plane and in-plane stability of arch. Therefore, the research about the stability of cable-arch structure are both valuable not only in theoretical research but also in design of engineering structure.

3061