内力

The P-A effect caused by gravity load makes internal force and displacement of structure larger, even instable.

重力荷载引起的P-△效应使结构的内力和位移增加，甚至失稳。

Distinguishing methods of various zero members i n special node s are summarized as well as the method how to utilize the symmetry of structure to build local coordinate system correctly for simplified internal force calculation of plane truss.

归纳了特殊结点中各种零杆的判别方法，总结了如何正确地建立坐标系和利用结构的对称性，以便达到简化平面桁架内力计算的目

Based on the conception of the equivalent stress,the expressions of the equivalent stress was educed. In this optimal design, the macro file for calculating the equivalent stress of arch dam is complied by using the parameter design language of the software, and the optimal design for shape of arch dam using equivalent stress as stress restraint condition is carried out.

本文基于等效应力概念，推导了拱坝有限元等效应力计算公式，将有限元法求得的坝体与基岩交接面上的应力合成截面内力，然后求出对应的线性化应力，并以此应力作为应力约束条件，实现了以等效应力作为应力约束条件进行拱坝体形优化。

MANDER constructive model is used to simulate stress-strain relationship of confined concrete; three sensitive parameters (pier height, confined index and concrete strength) are analyzed and the effect rule that how non-linear constructive model of reinforced concrete affects load of high pier is obtained.

由于高桥墩的几何非线性及材料非线性本构关系所导致的二次效应非常显著，因此采用传统的以弹性理论为基础的设计计算方法求算高柔桥墩的内力和变形会引起较大偏差。

With an example, the paper uses finite element program ANSYS to establish three calculating model of the steel-concrete composite open-web floor: the combination finite element method of spatial beam elements and shell elements, the finite element method of shell elements and the combination finite element method of shell elements and entity element.

结合一算例，利用ANSYS有限元软件，建立了组合空腹楼盖的三种计算模型：空间梁单元与壳单元的混合元模型、空间壳单元模型、壳单元和块体单元模型三种理论计算方法，对这三种计算模型作分析对比，得到了静荷载作用下该类结构的内力分布规律及其他一些有价值的结论。

By looking at the molecular chain rotation view of molecular changes in the internal force method!

通过查看分子链的旋转查看分子内力的变化方法！

We also explanated the distribution of moment and shear force in the four piers of the bridge in deferent stage of apllying loads.

并计算出在每个双柱墩的墩底，两个墩柱在内力分配中的规律。

Flexural rigidity of plate is reduced because of circular holes in the plate made by hollow pipes. And it generates the change of moment distribution in the plate.

由于楼板中埋入空心管使得楼板的刚度发生变化，从而使无梁空心板的内力分布相应的发生变化。

Then a discussion is made on the collapse pattern of the column, showing that the damage is caused by a combination of bending moment and axis force.

相邻断面间地层的响应差异也对结构内力产生了较大的影响。

Use the cubic function to be the displacement funtion, then base on the energy variation principle, the natural vibration equation is derived, which considers the pressure force and the boundary conditions of the compressed bar.

采用三次函数作为压杆单元的位移函数，基于能量变分原理，构造了一种可以考虑初始内力及边界条件的压杆单元。

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％。