THE METHOD OF MATRICES CONJOINT MULTIPLICATION FOR THE PROBLEM OF CIRCULAR ARC CORRUGATED DIAPHRAGM

The circular are corrugated diaphragms are taken in this paper as structures of several sections of the ring shells and a central circular plate matrices and link matrices are derivedhy using Prof.Chien the ring shells and perturbation theory of the circular thin plates.Through the of matrices conjoint multiplication.the linear exact solution and nonlinear soluman areobtained.The results agree with that of the experiments presentd by W.A.Wildha .     

双曲冷却塔与土壤相互作用时的随机阵风响应

本文在文[6]的基础上,应用随机振动的谱分析法和全尺寸风压的实测数据,分析了双曲冷却塔壳-支承系统-基础-无限域土壤这一完整系统的随机阵风响应,得到壳体和环形基础的阵风响应因子。文中考虑了不同类型的土壤和风压相关性等因素对阵风响应因子的影响,并给出数值计算结果。     

On discrete supports and continued support of structures

There have been several papers dealing with elastic discrete supports of structures. And we are interested in what relation there is between elastic discrete supports and continued support and what difference would result in for dynamic properties of structures under the two kinds of support. Through the present analysis, it is pointed out that natural frequencies reflect a certain proportion of kinetic and potential energies in total energy of a system, and the frequencies can be guaranteed to be invariable in transforming between elastic discrete and continued supports by means of a proper energy equivalence. And the theoretical formulation of beams and numerical results of shells of revolution are presented in this paper.     

The method of matrices conjoint multiplication for the problem of circular arc corrugated diaphragm

The circular are corrugated diaphragins are taken in this paper and structures of several sections of the ring shells and a central cireular plale I matrices and link matrices are derived by using Prof. Chuen Hei-zang’s general the ring shell[1] and perturbation theory of the circular thin plates. Throngh the meined of matrices conjoint multiplication, the linear exact solution and nonlinear soluaen are obtained. The resutts agree with that of the experiments presented by W. A. Wildhack..     

A PERTURBATION-VARIATIONAL SOLUTION OF THE LARGE DEFLECTION OF RECTANGULAR PLATES UNDER UNIFORM LOAD

In this paper,von Kármàn’s set of nonlinear equation for large deflection ofrectangular plates is at first converted into several sets of linear equations by taking centraldimensionless deflection as perturbation parameter,and then,the sets of linear equationsfor plates with various ratios of length to width are solved with application of variationalmethod.The analytical expressions for displacements and stresses as well as formulas fornumerical calculation are worked out.The figures of maximum deflection-load andmaximum stress with ratio λ of length to width as a parameter are given in this paper.Through comparison,it is found that the results of this paper are quite in accord withexperiments.     

结构中的离散弹性支承

有几篇文章已经涉及结构的离散弹性支承.它与连续弹性支承有什么关系,两种支承情况对于结构动力特性产生多大差异,这是人们关心的问题.本文通过分析指出,频率是反应系统总能量中动能和势能的比例关系,离散支承和连续支承之间通过某种能量的等效转化,可保证频率不变.并给出了梁的理论推导和旋转壳的的数值结果.     

圆弧形波纹膜片的矩阵联乘解法

将圆弧形波纹膜片看作几段圆环壳和中心圆板的组合构件,本文利用钱伟长教授的圆环壳一般解[1]及圆薄板小参数振动理论[2],导出环壳和板的传递矩阵和连接矩阵,用矩阵联乘法求得线性精确解和非线性解,计算结果同W.A.Wildhack的实验[3]是吻合的.     

均布载荷下矩形板大挠度问题的摄动变分解

本文以中心挠度为摄动参数,将矩形板大挠度问题的非线性偏微分方程组转化成几个线性偏微分方程,然后用变分法求解,得出了具有任意长宽比的板的解答,给出了位移、挠度及各内力的解析表达式;并给出中心点和边界中心的应力数值计算公式。本文还以长宽比λ为参数,作出了最大挠度——载荷曲线及最大应力曲线。其结果与实验进行了比较,表明二者是一致的。     

ON THE CIRCULAR FOOTING PLATES ON TWO-PARAMETERS FOUNDATION UNDER ARBITRARY LOADS

Modelling soils by two-parameter foundation model,this paper calculates thedistributions of displacements of circular footing plates on soils and reactions of soils underarbitrary loads using semi-analytical finite element method. And it improves V.Z. Vlazov’ssolution in the case of axisymmetry. The results agree well in comparison with those byF E M.At the same time,the boundary conditions of circular plates on soils arediscussed.     

考虑环形基础及土壤刚度时双曲冷却塔的动力特性

近年来,已有许多关于双曲冷却塔动力特性的文章.但塔壳的底部都是固定的,或者将其离散支柱系统考虑为弹性边界条件.本文将双曲冷却塔的离散柱支承系统处理为一个等效的壳体单元,同时考虑双曲冷却塔的环形基础及土壤刚度,使用解析法与半解析有限元法相结合计算了完整的双曲冷却塔系统的动力特性.其自然频率比不考虑环形基础和土壤刚度时略低一些,而冷却塔的振形则变化较大。