单层球面网壳火灾爆炸动力响应

摘要

The Kiewitt-8 single-layer reticulated domes were taken as case study.Considering the influence of geometric nonlinearity and temperature on the properties of the material,the dynamic behavior of the single-layer reticulated domes subjected to blast loading in different fire stages was simulated.According to the B-R criterion,the dynamic stability critical overpressure loads of K8 single-layer reticulated domes subjected to blast loading in different fire stages could be determined by the relationship between the peak overpressure of blast and the structural dynamic response.And the influence of parameters such as the risespan ratio,the roof load and the constraint settings on the dynamic stability of single-layer reticulated domes subjected to blast loading in different fire stages were analyzed.The results show that fires have a great influence on the dynamic stability of the reticulated domes under the impact of explosion,When the maximum temperature of the reticulated dome rods rises to more than 500℃,the anti-explosion ability of the dome greatly decreases.The rise-span ratio,the roof load and the restraint settings have different effects on the anti-blast ability of the reticulated domes in different fire stages.%以K8型单层球面网壳为研究对象,考虑几何非线性和温度对材料性能的影响,完整模拟了单层球面网壳在发生火灾的不同阶段受到爆炸冲击作用时的动力性状.据B-R准则,通过爆炸峰值超压与结构动力特征响应之间的关系,可判定K8型单层球面网壳在不同火灾阶段,爆炸冲击作用下的动力稳定性临界峰值超压.分析了单层球面网壳的矢跨比、屋面荷载、约束布置等参数对其在不同火灾阶段的爆炸冲击动力稳定性的影响.研究表明:火灾对网壳结构在爆炸冲击作用下的动力稳定性有较大影响,当网壳杆件最高温度达500℃以上时,结构的抗爆能力明显降低.矢跨比、屋面质量、约束布置对网壳在火灾不同阶段的抗爆能力均有不同程度的影响.