均布荷载作用下两端固支梁的弹塑性分析

通过单位荷载法分析了两端固支超静定梁在均布荷载作用下的弹塑性加载及变形过程，并给出了加载各阶段的弯矩和位移计算公式．分析结果表明，受力变形过程可分为4个阶段：弹性阶段：固支端附近产生塑性变形阶段；固支端为塑性铰而固支端附近塑性区卸载阶段；固支端保持为塑性铰而梁中部部分区域产生塑性变形直至形成塑性流动阶段．

Elastic-plastic analysis of beams fixed at two ends subjected to uniformly-distributed loads

The elastic-plastic loading and deformation process of the statically-indeterminate beam fixed at two ends under uniformly-distributed loads was analyzed by use of the unit-load method, and formulas for bending moment and displacement at different loading stages were derived. The result of analysis shows that the deformation process can be divided into four stages, including the stage of elastic deformation of the whole beam, the stage of plastic deformation occurring in the region close to two fixed ends, the stage of unloading in plastic regions with two plastic hinges at the fixed ends, and the stage of plastic deformation till the occurrence of plastic yield at the middle of the beam with two plastic hinges at the fixed ends.