具有波阻抗不连续特性的粘弹性介质中的逆散射问题

在时间域内讨论了粘弹性介质的逆散射问题,其中粘弹性介质的波阻抗在远离入射波作用面一侧的交界面上是不连接的。介质的散射算子,传播算子所满足的微分积分方程可以用来反演未知的粘弹性介质的松弛模量,文中给出的反演过程只须利用介质层一侧的反射算子在一个走时来回的时间内的实验测量数据。最后,给出了数值算例,计算结果表明,利用方法可以较准确的反演得到材料松弛模量。     

具有分数导数本构关系的粘弹性Timoshenko梁的静动力学行为分析

利用粘弹性材料的三维分数导数型本构关系,建立粘弹性Timoshenko梁的静、动力学行为研究的数学模型;分析Timoshenko梁在阶跃载荷作用下的准静态力学行为,得出了问题的解析解,考察了一些材料参数对梁的挠度的影响。基于模态函数讨论了粘弹性Timoshenko梁在横向简谐激励作用下的动力响应,并考察了剪切和转动惯性对梁振动响应的影响。     

Boundary element method for solving dynamical response of viscoelastic thin plate (I)

I.lntroducti0nThedynamicresponseofviscoelasticstructuresisoneofimportantresearchdirectionsinsolidmechanics.BecauseofthecompIexityoftheconstitutiverelations0fviscoeIasticmaterials,theproblemofsolvingthedynamicresponseisverydifflcult.Therearesomeavailablenu…     

开孔结构的稳定性分析及其应用

缺陷对结构稳定性的影响是直接与结构失效分析有关的重要课题．本文把板壳结构中存在的孔洞作为一种几何缺陷,简述了开孔柱壳非线性分析的理论、变分原理、有限元方法及其对稳定性分析的应用．考察了孔洞的存在对轴压柱壳临界载荷的影响      

粘弹性与弹性平面问题间的某些恒等关系*

本文以应力函数F(x_a,t)为基本未知量,首先建立了各向同性、线性粘弹性平面问题(开孔与不开孔)的基本边值问题;其次,详细讨论了粘弹性与弹性平面问题之间位移和应力的某些恒等关系,得到了若干重要和有意义的结论.作为应用,研究了具有中心微孔的粘弹性平板在单向拉伸时微孔的变形响应.     

The existence of buckled states on a perforated thin plate

On the basis of the generalized yon Kàrmàn theory for perforated thin plates established in [1, 2], the existence of buckled states for perforated plates subjected to self-equilibrating inplane forces along each edge systematically is investigated. This work completely generalizes the results in [3, 4].     

The buckled states of annular sandwich plates

In this paper, the axisymmetric buckled states of an annular sandwich plate (Reissner- type sandwich plate) with the clamped inner edge which is subjected to a uniform radial compressive thrust at the clamped outer edge are studied. Firstly, the basic equation of the buckled problem is derived. Secondly, the critical loads for some parameters are obtained by using the shooting method. Finally, we discuss the existence of the buckled states in the vicinity of the critical loads and obtain the asymptotic expansions of the buckled states.     

弹性基础上环形板的屈曲和过屈曲

基于von Kármán方程,本文利用打靶法系统地讨论了弹性基础上环形板的轴对称屈曲和过屈曲.     

复合载荷下环形薄板的热屈曲*

基于von K×rm×n薄板大挠度方程,本文研究了经受非均匀轴对称温度场的环形薄板在多种边界条件下的热屈曲问题.采用分析与计算相结合的方法着重讨论了热屈曲的线性化问题,获得了反映环板失稳特征的稳定边界.     

Buckling and post-buckling of annular plates on an elastic foundation

On the basis of von Kárman equations,the axisymmetric buckling and post-bucklingof annular plates on anelastic foundation is(?)tematically discussed byusing shootingmethods.