铝合金板式节点网壳非破坏性火灾响应试验研究  

Nondestructive experimental study on fire response of aluminum alloy reticulated shells with gusset joints

作　　者：郭小农[1] 陈晨 朱劭骏 蒋首超[1] GUO Xiaonong;CHEN Chen;ZHU Shaojun;JIANG Shouchao(College of Civil Engineering,Tongji University,Shanghai 200092,China)

机构地区：[1]同济大学土木工程学院,上海200092

出　　处：《建筑结构学报》2021年第6期72-84,共13页Journal of Building Structures

基　　金：国家自然科学基金项目(51478335)。

摘　　要：为研究铝合金板式节点网壳结构在实际火灾下的响应,针对一网壳缩尺模型进行了结构受火试验。采用柴油油池火作为火源,考虑不同的火源功率、火源位置和通风条件,设计了8个受火场景。在结构受火试验前,进行了两次柴油燃烧特性试验,并将试验结果与经典羽流模型的预测值进行了对比分析。结构受火试验结果表明:空间温度场在大空间火灾下分布不均匀,且火源位置和火源功率对结构温度场分布具有较大影响;在各受火场景中,大功率火源位于结构角部且通风条件不佳时为最不利火灾场景;在该火灾场景下,所测得的最高空气温度为128℃,而杆件和节点板的最高实测温度分别为92℃和84℃;在所有结构模型受火试验过程中,均发现网壳发生起拱变形,但试验结束后变形可恢复,且未观测到其他破坏现象。对试验过程进行数值模拟,结果表明火灾下结构的热膨胀变形可能提升其稳定承载力,因此在设计时建议分别基于有热膨胀变形和无热膨胀变形的结构进行稳定承载力分析,并取两者结果中的较小值作为结构火灾下承载力的设计值。In order to study the response of aluminum alloy reticulated shells with gusset joints under real fire conditions, a series of structural fire tests were carried out on a scaled model. Diesel oil was chosen to be the fuel of the fire tests. Considering various fire power, fire locations and ventilation conditions, eight fire scenarios were designed. Before the structural fire tests, two diesel pool fire tests were carried out, and the test results were compared against the classical plume models. The results of structural fire tests show that the distribution of temperature field in large space fire is uneven, and the locations and power of the fire have great influences on the temperature distribution. The most adverse fire scenario is that the high power fire is located at the corner of the model with poor ventilation conditions, and the maximum measured air temperature is 128 ℃, the maximum measured temperature of the members and gusset plates are 92 ℃ and 84 ℃, respectively. During the process of the structural fire tests, the tested shells undergo arching, and the displacement is in the elastic region. No damage or permanent deformation is observed after tests.The test process is simulated numerically, and the results indicate that the thermal expansion of the structure may increase the stability capacity. Therefore, it is suggested that in the design process, the structures with and without thermal expansion should both be analyzed, and the lower stability capacity should be taken as the design value.

关 键 词：铝合金网壳 板式节点 受火试验 火灾响应 

分 类 号：TU395.02[建筑科学—结构工程] TU317.1