强雪荷载下陕西自然博物馆单层网壳的抗垮塌可靠度研究

Anti-collapse reliability of single-layer reticulated shell of Shaanxi Nature Museum under heavy snow load

单层网壳结构对雪荷载比较敏感,常会发生由雪荷载导致的垮塌事故.以陕西省自然博物馆为研究对象,对其进行雪荷载作用下的抗垮塌性能研究.首先,考虑雪荷载的不同分布并结合双重非线性和初始缺陷因素,采用直接分析法对结构进行抗垮塌性能分析,得到最不利雪荷载分布以及极限荷载,并与引入杆件失稳的结构比较抗垮塌性能.然后,采用蒙特卡罗法和拉丁超立方体抽样法,分析该网壳在全跨雪荷载分布下的抗垮塌可靠度.本研究可为单层网壳结构在强雪荷载作用下的设计提供参考.

The single-layer reticulated shell structure is sensitive to snow load,therefore collapse accidents caused by snow load often occur.In this paper,the single-layer reticulated shell of Shaanxi Nature Museum was taken as the research object.Its anti-collapse reliability under snow load was studied.First of all,considering the different distributions of snow loads and combining the factors of double nonlinearity and initial defects,direct analysis method was adopted to analyze the anti-collapse performance of the structure.The distribution of the most unfavorable snow load and the ultimate load were obtained,and the collapse resistance performance of the structure was compared with that of the structure with member instability.Then Monte Carlo method and Latin hypercube sampling method were used to calculate the anti-collapse reliability of the reticulated shell under snow load evenly distributed across the whole span.This study provides a reference for the design of single-layer reticulated shell structures under heavy snow load.