Exploring fire resistance of high strength steel end-plate connections is one of the key technical bases for fire resistance design and fire safety assessment of high strength steel structures. Numerical simulation and parameter analyses of high strength Q690 steel flush end-plates will contribute to a reasonable design of high strength flush end-plate connections. In this paper, a finite element model of high strength steel flush end-plate connection considering thermal creep effect was established and validated by experimental results. The thermal creep finite element model can simulate accurately heat performance, failure modes and deformations of high strength flush end-plate connections at elevated temperatures. The increase of axial compression ratio has little effect on rotation, deflection, failure time, critical temperature, and critical rotation with elevated temperatures. The increase of bending moment ratio has little effect on the development trend of rotation and deflection. Proper increase of thickness of the end-plate can improve failure time and critical rotation, and the increase range is within 7% and 36% respectively. Proper increase of diameter of bolt can improve failure time, critical temperature, and critical rotation to a certain extent, and the increase range is within 10%, 6% and 27% respectively. Proper increases of thickness of the end-plate and diameter of bolt will improve the fire resistance of flush end-plate connection.

探索高强钢端板连接的耐火性能是高强钢结构耐火设计和消防安全评估的关键技术基础之一。高强度Q690钢平端板的数值模拟和参数分析将有助于高强度平端板连接的合理设计。本文建立了考虑热蠕变效应的高强钢平端板连接有限元模型，并通过实验结果进行了验证。热蠕变有限元模型可以准确模拟高温下高强度齐平端板连接的热性能、失效模式和变形。轴压比的增加对旋转、挠度、失效时间、临界温度以及随温度升高的临界旋转影响不大。弯矩比的增大对旋转和挠度的发展趋势影响不大。适当增加端板厚度可以改善失效时间和临界旋转，增加幅度分别在7%和36%以内。适当增加螺栓直径可以在一定程度上改善失效时间、临界温度和临界旋转，增加幅度分别在10%、6%和27%以内。适当增加端板厚度和螺栓直径，可提高齐平端板连接的耐火性能。