梁的扰度问题

xsrose376

如图，一个有折弯的梁，A端通过M3的螺钉（预紧力大概1000N）拧在红色的立柱上，立柱跟地面固定，B端悬空。不知道这种情况应该简化成什么力学模型，简支梁？B端会有挠度吗，如果有应该如何计算？螺钉的预紧力要用在计算当中吗？

shihongjiao

严格来说是弹性支座。不严格分析的话，悬臂即可。另一角度说，力较大就弹性支座分析，力很小，就弹性支座分析

iambadman

同想知道，，另外预紧力应该不用考虑

tonnyw

Let us neglect the effect of dead weight. I think the end B should have deflection due to the pretension on the point A. But the deflection should be small.

You can use brick element model to compute the deflection at point B.

Or you can use beam elements for the two pieces on the left side of the horizontal piece which has point A. Then for the horizontal part you can use brick element. But at the interface between beam element and brick element, you have to couple the dofs.

To simulate the pretension, you can simply use a truss element and apply temperature drop dt such that E*A*alpha*dt = 1000N. Here you also need to couple the dofs. between brick element and truss element.  

Let us know the results.

zxkcup

shihongjiao说得对，理论计算的话如上简化即可，有限元模拟的话，尽量和实际相符合为好