Tài liệu Cơ Khí - Chế Tạo Máy

Improved estimates for the effective elastic bulk modulus of random tetragonal crystal aggregates
In this paper we have derived explicit expressions of the general shape-unspecified upper and lower bounds on the effective elastic bulk modulus of random tetragonal crystal aggregates with numerical illustrations. The estimates are expected to predict the scatter range of the macroscopic elastic property of practical polycrystalline materials. On...
12 trang | Chia sẻ: huongthu9 | Ngày: 11/08/2021 | Lượt xem: 565 | Lượt tải: 0
Frequency response of a beam-Like structure to moving harmonic forces
The moving load problem for a long time has attracted attention of researchers and engineers in the field of structural engineering and it is so far an actual topic in dynamics of structures. The fundamentals of the problem were formulated in [1–5] and intensively studied in the widespread literature, for example, the references [6–11]. In the m...
16 trang | Chia sẻ: huongthu9 | Ngày: 11/08/2021 | Lượt xem: 626 | Lượt tải: 0
An analytic homogenization model in traction and bending for orthotropic composite plates with the type of double corrugated cardboard
In this article, we have proposed an analytic homogenization model for the traction and flexion problem of double corrugated core cardboards. The comparison of the results obtained by the analytic formulas, by the Abaqus 3D simulations and by the AbaqusUgens 2D simulations has proved the validation of the present traction and flexion homogenizati...
9 trang | Chia sẻ: huongthu9 | Ngày: 11/08/2021 | Lượt xem: 648 | Lượt tải: 0
Tính toán động lực học công trình biển cố định hệ thanh không gian chịu tác động của tải trọng sóng và gió với mô hình lý thuyết sóng stoke bậc 2
This paper presents finite element algorithms and dynamic analysis of the jacket type offshore structure under water wave and wind impact by using stoke’s second order wave theory. The result of the paper is the scientific basis for the calculation, design and selection of the appropriate parameters, the study contributes to the optimization of ...
9 trang | Chia sẻ: huongthu9 | Ngày: 11/08/2021 | Lượt xem: 674 | Lượt tải: 0
Engineering optimization by constrained differential evolution with nearest neighbor comparison
This paper presented the combination of the nearest neighbor comparison, previously used within unconstrained optimization, and the # constrained method for handling constraints and proposed the #DE-NNC for constrained engineering design problem. The performance of #DE-NNC was evaluated by five widely used engineering benchmark design problems. It...
13 trang | Chia sẻ: huongthu9 | Ngày: 11/08/2021 | Lượt xem: 570 | Lượt tải: 0
Vibration analysis of beams subjected to random excitation by the dual criterion of equivalent linearization
The method of equivalent linearization is one of effective tools in solving random vibration problems of mechanical systems. In this study, the modal responses of a simply supported beam subjected to a space-wise and time-wise white noise loading are carried out by the dual criterion of equivalent linearization. Our calculations are restricted i...
14 trang | Chia sẻ: huongthu9 | Ngày: 11/08/2021 | Lượt xem: 547 | Lượt tải: 0
Free vibration of functionally graded sandwich plates with stiffeners based on the third-Order shear deformation theory
This paper investigates the free vibration behavior of stiffened FG sandwich plates based on the third order shear deformation and using the finite element method. Two plate configurations, i.e., plate with FG face-sheets and the homogenous core are metal and ceramic, respectively, are considered. The present results are compared to analytical ...
20 trang | Chia sẻ: huongthu9 | Ngày: 11/08/2021 | Lượt xem: 585 | Lượt tải: 0
Thermomechanical postbuckling of thick fgm plates resting on elastic foundations with tangential edge constraints
The thermal and thermomechanical postbuckling behavior of thick FGM plates resting on elastic foundations with tangentially restrained edges have been analyzed. The analysis reveals that the tangential constraints of boundary edges has extremely sensitive influences on the buckling and postbuckling of FGM plates. Specifically, critical buckling ...
17 trang | Chia sẻ: huongthu9 | Ngày: 11/08/2021 | Lượt xem: 576 | Lượt tải: 0
Postbuckling of thick fgm cylindrical panels with tangential edge constraints and temperature dependent properties
The nonlinear response and postbuckling behavior of thick FGM cylindrical panels subjected to thermal, mechanical and thermomechanical loadings have been analyzed. Formulations are based on the higher order shear deformation shell theory taking geometrical nonlinearity, initial imperfection, panel-foundation interaction, tangential edge constrai...
18 trang | Chia sẻ: huongthu9 | Ngày: 11/08/2021 | Lượt xem: 551 | Lượt tải: 0
Free vibration of a cracked double-Beam carrying a concentrated mass
In this paper, the influence of a concentrated mass on the natural frequencies of a double-beam consisting of two different simply supported beams is presented. When there is a concentrated mass the natural frequencies of the double-beam change. The changes in natural frequencies depend on the location of the mass and the mode shapes of the dou...
15 trang | Chia sẻ: huongthu9 | Ngày: 11/08/2021 | Lượt xem: 551 | Lượt tải: 0