铝合金板式节点网壳破坏性火灾试验

为研究铝合金板式节点网壳结构在火灾下的破坏模式,采用柴油油池火对一网壳缩尺模型进行了2次破坏性火灾试验.研究结果表明,当火源功率为2 MW(对应原型火源功率为110 MW)且置于地面位置燃烧时,铝合金网壳模型所产生的变形均在试验结束后恢复,且未观测到影响结构宏观承载性能的永久变形.为了模拟局部特大功率火灾场景,将同功率...

Destructive fire tests on aluminum alloy reticulated shells with gusset joints

In order to study the failure modes of aluminum alloy shells with gusset joints under real fire conditions, two destructive fire tests were carried out on a scale model. Diesel pool fire was chosen to be the fuel of the fire tests. The results show that through the test under a 2MW (corresponding to 110MW in the prototype) fire located at the center on the ground, the deformation of the aluminum alloy shell specimen recovers and no permanent deformation that will influence the mechanical behavior of the specimen is observed after test. In order to simulate rare localized extra-large fire scenario, the 2MW fire was located at the height of 1.35 m. The collapse of the reticulated shell structure is observed at the combustion time of 528 s. The members fail by melting, rupture and flexural-torsional buckling. According to the results of the fire tests, the non-uniform temperature distribution is beneficial for large-space structures to bear load, which is suggested to be considered in the field simulation or the empirical formula. In addition, PyroSim and FDS were used to analyze the temperature field of the experimental model. Through the comparison of the air temperature-time curves and the smoke movement, the reliability of the established model was verified.