高强钢端板连接节点火灾下性能试验与理论研究

Experimental and theoretical study on behavior of high strength steel endplate connections under fire conditions

摘要:

采用稳态火灾试验方法,对7个梁柱端板连接节点在550℃的火灾高温下开展足尺试验研究,得到此类节点在火灾下的受力性能以及失效机理。节点试件包括4个高强钢端板连接节点和3个普通钢端板连接节点,所研究参数为端板材料和端板厚度。为对比分析,同时对上述7个节点试件在常温下的相应力学性能进行试验研究。此外,将试验结果同现行欧洲钢结构设计规范Eurocode3中相应条文进行对比分析。研究表明,无论在常温下还是在火灾高温下,同普通钢端板连接节点相比,采用相对较薄的高强钢端板可在提高节点转动能力的同时不影响其抗弯承载力,从而确保结构整体的安全性能。

Abstract:

In order to obtain behavior and failure mechanisms of high strength steel endplate connections in fire, full-scale tests on 7 joints were conducted at elevated temperature 550℃ under steady state fire condition. The connection specimens included 4 high strength steel endplate connections and 3 mild steel endplate connections. The endplate thickness and the endplate material are the focus of the parametric study. In order to compare, corresponding tests at ambient temperature were carried out as well. Moreover, the current provisions of Eurocode 3 were validated with experimental results. It is found that a proper thinner high strength steel endplate can improve the rotation capacity of connection both at ambient temperature and in fire, and simultaneously achieve similar moment resistance with a mild steel endplate connection, which guarantees the safety of an entire steel structure.