有限元法

A new non-conforming finite element FE eigenanalysis method is developed to determine the order and angular variation of singular stress states at material and geometric discontinuities in anisotropic materials subject to antiplane shear loading.

提出采用一种非协调元有限元特征法来计算各向异性材料在反平面剪切载荷作用下的奇性应力指数和奇性场角分布。该方法没有采用奇异变换技术。与以前的几种解析法比较，结果表明这种方法的收敛性好，精度高，可以求解关于复杂几何体问题

This thesis consists of two parts. The first one was that boundary value problem was discrete with five point difference method. Three kinds of memory formats were studied, which were full matrix, half band width and row compress sparse. Full matrix memory format and half band width memory format first was contrasted. The results show that half band width has efficiency in space. Then the algebraic system of finite element method was solved by Gauss-Seidel iteration method to popular row compress sparse memory format.

本论文由两部分组成，第1部分针对边值问题，用5点差分格式进行离散，并对离散矩阵这类大型稀疏矩阵，研究了系数矩阵的3种存储格式的优劣，即：满矩阵存储格式、半带宽存储格式和按行压缩稀疏存储格式，首先我们将满矩阵存储方式和半带宽存储格式进行了对比，迭代法的数值实验表明：利用半带宽存储的矩阵在空间运算方面具有高效性；然后针对目前数值实验中流行的按行压缩稀疏存储格式，实现了有限元离散代数系统的迭代法的求解。

The paper includes:The author calculate the structures inner force and displacement of the free end , analyze the influence of the height and the value of pretress of cable by making use of ANSYS 9.0 soft, pose the concept of critical prestress,conclude the function relation between displacement of the free end, initial strain and the height of cable ,analyze the dynamic properity and point out that Newmark-β method should be adopted when we analyze the dynamic properity of the cable-stayed spatial structure with direct integral test to guarantee the contribution of high mode,finally conclude the functional relation among coefficient of earthquake inner force, initial strain and the height of cable, wish to get some helpful conclusion applied to cable-stayed spatial truss design.

本文系统介绍了斜拉空间桁架竖向地震反应的分析理论与方法、详细分析了斜拉空间桁架结构在静力和竖向地震作用下的受力性能，主要内容包括：利用通用有限元软件ANSYS9.0计算了斜拉空间桁架在静力和竖向地震作用下内力及自由端位移分布规律并得出地震内力系数与节间位置、预应力以及斜拉索高度之间的函数关系；详细分析了斜拉索中施加的预应力以及斜拉索高度的变化对于该种结构内力及自由端位移的影响并提出了斜拉空间桁架的临界预应变概念，进而得到了自由端位移与初始预应变以及斜拉索高度的函数关系，即：△=-(40h+2180)ε+9.8；分析了该种结构的动力性能，并指出：在时域内采用直接积分法计算该种结构的动力响应时，应该考虑采用不引起振幅率减小的Newmark-β法，以保证高阶模态响应的贡献仍然保留在响应中而不致于被忽略。

This study validate that it also can be used for distortional buckling beam-column under the condition of distortional buckling load calculated by the above formula.

本文用直接强度法来计算压弯构件在发生畸变屈曲时的承载能力，把计算结果同有限元模拟结果进行对比，验证在压弯构件畸变屈曲时直接强度法的适用性。

Utilizing plane sectorial domain Hamilton system function via variable substitutes and eigenfunction expansion method, an analytical element is proposed in this paper for the crack analysis of reinforced concrete structures combining the bridging model and Dugdale model. Combined with finite element, nolinear crack problems of reinforced concrete structure can be analyzed.

利用平面扇形域哈密顿体系方程，通过分离变量法及共轭辛本征函数向量展开法，结合Dugdale模型和桥联力模型，推导了钢筋混凝土结构裂纹尖端的解析元列式，将此解析元与普通有限元结合，可用于分析钢筋混凝土的非线性断裂问题。

At the same time, the mix fixed point method and the nonsmooth Newton method for finite element method are also presentedBased on the Gauss point method for seepage problem with free surface, the non-smooth equations model for seepage problem is proposed as well as the mix fixed point method which belongs to the fixed mesh method.

本文根据近些年来求解可动边界的经验和非光滑分析的发展，建立了求解渗流自由面的数学模型，提出了求解渗流自由面的有限元混合不动点法和非光滑牛顿法。

The Galerkin FEM equations are deduced in detail. And the property of convergence are discussed. The PICCG method is improved in which the merits of PICCG and ICCG method are combined.

详细推导了E-E-ψ法的Galerkin有限元方程，并讨论了其收敛过程，对PICCG算法作了改进，组合了PICCG法和ICCG算法的优点，称为PICCG算法。

It combines the geometrical flexibility of the Finite element method and the accuracy of the pseudospectral method. Here, the theory and the deducing process of the SEM based on the Legendre polynomial is given.

本文采用谱元法对横向同性介质中的地震波进行模拟，该方法基于弹性力学方程弱形式基础之上，具有有限元适应任意复杂介质模型的韧性和伪谱法的精度。

In the text, the Spectral element method is used to model the seismic wave propagation, which is based on a weak formulation of the elastic mechanics equation. It combines the geometrical flexibility of the Finite element method and the accuracy of the pseudospectral method.

本文采用谱元法对横向同性介质中的地震波进行模拟，该方法基于弹性力学方程弱形式基础之上，具有有限元适应任意复杂介质模型的韧性和伪谱法的精度。

Based on the finite element method,the minium energy principle and the voltage equilibrium principle have been developed to calculate the ampere-turn distribution of parallel coils in a shell-type transformers.

本文基于有限元技术，提出计算壳式铁心变压器并联线圈中电流分配的最小能量法和电压平衡法，并证明了两种方法的等价性。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。