不均匀分布雪荷载作用下门式刚架稳定性分析

The stability analysis of the portal frame under the effect of the unbalanced distribution of the Snow

雪荷载为轻钢结构敏感荷载,在寒冷地区不均匀雪荷载是导致结构倒塌的主要因素。本文首先对门式刚架结构屋面积雪分布形态进行实测,进而采用大型有限元分析软件ansys对不同形态雪荷载作用下的结构进行稳定性研究。获得以下结论:均匀雪荷载作用下结构稳定性最大,1/2跨雪荷载作用下结构稳定性较小,1/4跨雪荷载作用下结构稳定性最小;结构稳定性随着屋面坡度的增加而提高;结构初始缺陷对结构稳定性产生不利影响;柱脚采用刚接比采用铰接结构稳定性大。

Snow load is sensitive to light steel structure. The unbalance distribution of the snow is the main factor leading to the collapse of the structure in the cold area. Firstly, we conducted the field measurement of characteristics of snow distributions on the roof, and then using the large-scale finite element analysis software ANSYS to research on the stability of structure under the different forms of snow load. Obtained the following conclusions, structural stability under uniform snow load maximum, structure stability under half span snow load structural stability is small, 1/4 span snow load minimum; structural stability increase with the slope roof; structure stability with rigid connection column is higher than the articulated structure.