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961.
ZhengJunjie PengHong NieChongjun 《Acta Mechanica Solida Sinica》2004,17(4):353-360
Based on the results of conventional triaxial compression tests for a soil, a trilinear elasto-plastic model is proposed to simulate the stress-strain softening curve. According to this curve, the constitutive relation between the bulk strain and two pr… 相似文献
962.
The title problem is given the following explicit solution: =
D
S|D, where the elasticity tensor in the constrained case is the restriction to the constraint subspace D of a corresponding unconstrained elasticity tensor S, followed by composition with the orthogonal projection
D
on D. 相似文献
963.
有限变形粘弹性接触的数学规划方法 总被引:2,自引:0,他引:2
研究有限变形粘弹性物体间的接触问题,同时考虑了刚体位移和摩擦等因素,导得该问题数学规划解法的标准形式,极易利用现有算法求解。 相似文献
964.
In this paper, 3-dimensional non-axisymmetrical deformation analyses for finite hollow circular cylinders have been carried
out by Pickett's double series expansion method[1]. Through expanding the displacement potentials as the sum of fourier series and Fourier-Bessel series, we could express the
coefficients of one series by those of another under certain boundary conditions. Thus, a set of linear algebraic equations
were derived. Solving these equations, we could obtain the solutions of the problems. Numerical examples have been given to
show that the method presented here is workable for practical applications. 相似文献
965.
We use Riccati's equations and the ordinary and exponential dichotomies to get simple recurrent formulae for the asymptotic integration of linear systems subjected to L
p
-perturbations with arbitrary p 1. Moreover, we establish conditions which are necessary and sufficient for the persistence of one-dimensional invariant subbundles for the linear system under L
p
-perturbations. In this way, we prove the sharp nature of the well known Levinson and Hartman–Wintner asymptotic theorems. 相似文献
966.
王文洽 《应用数学和力学(英文版)》2004,25(2)
IntroductionWeconsiderthefollowingnonlinearBurgers’equation : u t u u x=ε 2 u x2 , 0 0 ,( 1 )withtheinitialandtheboundaryconditions u(x,0 ) =f(x) , 0 相似文献
967.
本文选用考虑横向剪切效应的退化梁单元,引入几何非线性假设,对具粘弹性阻尼层的夹层梁动响应及其衰减效果进行了研究,得到了一些具有应用价值的结论。 相似文献
968.
969.
In this paper a basic, easily to multi-contact problems extendable, non-smooth approach is applied to analyze a bar striking an inelastic half-space. Coulomb contact is assumed and modeled by using set-valued Newtonian impact laws in normal as well as in tangential direction. The resulting linear complementarity problem contains all possible impact states and provides an instantaneous collision operator that respects all inequality constraints. This operator depends on the orientation of the bar and determines uniquely the post-impact velocities as functions of the pre-impact state. Different types of solutions may occur, including “stick’’ and “slip’’. In this context, stick and slip have to be understood as the two cases characterized by the tangential impulsive force as an element of either the set-valued or of the single-valued domain of the friction law. Depending on the choice of parameters, sign reversal of the tangential contact velocity is possible. For certain inertia properties and initial conditions, the collision operator yields an impact, even for initially vanishing normal contact velocity. This phenomenon is well known as the Painlevé paradox. The results obtained by this fully non-smooth rigid body approach are compared with those of other impact models, such as a lumped mass model with compliance elements, and a collision operator used for particle interactions in flows.AMR: 160A, 160B, 160Y, 292B, 292Y 相似文献
970.
A SINGULAR VALUE DECOMPOSITION BASED TRUNCATION ALGORITHM IN SOLVING THE STRUCTURAL DAMAGE EQUATIONS 总被引:1,自引:0,他引:1
RenWei-Xin 《Acta Mechanica Solida Sinica》2005,18(2):181-188
The structural damage identification through modal data often leads to solving a set of linear equations. Special numerical treatment is sometimes required for an accurate and stable solution owing to the ill conditioning of the equations. Based on the singular value decomposition (SVD) of the coefficient matrix, an error based truncation algorithm is proposed in this paper. By rejection of selected small singular values, the influence of noise can be reduced. A simply-supported beam is used as a simulation example to compare the results to other methods.Illustrative numerical examples demonstrate the good efficiency and stability of the algorithm in the nondestructive identification of structural damage through modal data. 相似文献