The Solution for Axisymmetrical Shells with Abrupt Curvature Change(Corrugated Shells)by the Finite Element Method

It has been noted in the present paper that the finite element method using linear elements for solving axisymmetrical shells cannot be applied to the analysis of axisymmetrical shells with abrupt curvature change,owing to the fact that the influence of the curvature upon the angular displace-ments has been neglected.The present paper provides a finite element method using linear elements in which the influence of curvature is considered and the angular displacements are treated as continuous parameters.This method has been applied to the calculation of corrugated shells of the type C,and compared with the experimental results obtained by Turner-Ford as well as with the analytical solution given by Prof.Chien Wei-zang.The compari-sons have been proved that this theory is correct.     

边界积分方程中超奇异积分的解法

本文对边界积分方程中所存在的超奇异积分的数值解法作了综述，并介绍了它的一些应用。     

PERTURBATION METHOD IN THE PROBLEM OF LARGE DEFLECTIONS OP CIRCULAR PLATES WITH NONUNIFORM THICKNESS

In this paper the perturbation method about two parameters is applied to the problem of large deflection of a cricular plate with exponentially varying thickness under uniform pressure.An asymptotic solution up to the third-order is derived. In comparison with the exact solutions in special cases, the asymptotic solution shows a precise accuracy.     

The perturbation finite element method for solving problems with nonlinear materials

The perturbation method is one of the effective methods for so-lving problems in nonlinear continuum mechanics.It has been de-veloped on the basis of the linear analytical solutions for the o-riginal problems.If a simple analytical solution cannot be ob-tained.we would encounter difficulties in applying this method tosolving certain complicated nonlinear problems.The finite ele-ment method appears to be in its turn a very useful means for sol-ving nonlinear problems,but generally it takes too much time incomputation.In the present paper a mixed approach,namely,theperturbation finite element method,is introduced,which incorpo-rates the advantages of the two above-mentioned methods and enablesus to solve more complicated nonlinear problems with great savingin computing time.Problems in the elastoplastic region have been discussed anda numerical solution for a plate with a central hole under tensionis given in this paper.     

组合梁的理论计算与实验

大专院校的材料力学实验课中引进了矩形梁的弯曲应力及变形实验,多年教学实践证明,这类实验对于学生的理论学习有一定的作用,但不能启发学生去思考问题,不能调动同学学习的积极性和培养学生解决问题的能力.在生产实践中,梁往往不是简单的矩形梁,如工厂用桥式吊车就大都是组合结构;吊车轨道梁则是钢筋混凝土梁上辅有钢轨,共同支撑起吊的重量;汽车板簧是由多层弯曲的钢板重叠组合而成的等等.     

The solution for axisymmetrical shells with abrupt curvature change (corrugated shells) by the finite element method

It has been noted in the present paper that the finite element method using linear elements for solving axisymmetrical shells cannot be applied to the analysis of axisymmetrical shells with abrupt curvature change, owing to the fact that the influence of the curvature upon the angular displacements has been neglected. The present paper provides a finite element method using linear elements in which the influence of curvature is considered and the angular displacements are treated as continuous parameters. This method has been applied to the calculation of corrugated shells of the type C, and compared with the experimental results obtained by Turner-Ford as well as with the analytical solution given by Prof. Chien Wei-zang. The comparisons have been proved that this theory is correct.     

摄动有限元法解一般轴对称壳几何非线性问题

本文在处理几何非线性问题时,利用在变分方程中引入振动过程,得到各级变分摄动方程,并通过有限元法求解.由于有限元法能成功地处理各种复杂边界条件、几何形状的力学问题,摄动法又可将非线性问题转化为线性问题求解.若结合这两种方法的优点,将能够解决大量复杂的非线性力学问题.并能够消除单独使用有限元法或摄动法求解复杂非线性问题所出现的困难. 本文应用摄动有限元法求解了一般轴对称壳的几何非线性问题.     

中西医结合治疗颅脑外伤后脑梗塞39例分析

目的探讨颅脑外伤后并脑梗塞的相关因素和中西医结合治疗的方法及预防措施.方法回顾性总结我科1994年1月至2005年1月收治的39例颅脑外伤后脑梗塞的中西医结合治疗及预防的临床经验.结果出院时按GOS评价,良好30例,中残5例,重残2例,死亡2例.结论对颅脑外伤合并脑梗塞应早期诊断,积极预防,早期中西医结合治疗,可有效减少和减轻脑梗塞的发生,提高患者的生存质量.     

云南白药结合EC胶治疗脑静脉窦损伤23例分析

目的探讨颅脑损伤中脑静脉窦损伤的简单、有效、适用于基层的处理方法。方法对1993年3月～2005年1月我科行中西医治疗的23例脑静脉窦损伤的患者进行了回顾性分析。结果本组23例,治愈21例,救治成功率91.3%,2例死亡,死亡率8.7%。结论云南白药结合EC胶治疗脑静脉窦损伤的效果良好。