高温下钢筋混凝土梁-柱节点的力学性能演化机制

Mechanical Property Evolution of Beams-Column Joints at Elevated Temperatures

摘要:

为研究钢筋混凝土框架梁?柱节点的火灾行为及其相互约束作用随温度的变化规律，开展了荷载?高温耦合作用下的钢筋混凝土框架梁升降温全过程的结构试验。在试验的基础上采用VULCAN程序进行了恒定荷载作用下框架梁单独受高温、梁?柱同时受高温，梁?柱节点弯矩?转角关系的火灾响应数值分析。结果表明，钢筋混凝土框架梁?柱节点的转动约束强度随温度的升高而降低，梁?柱节点转角峰值相较于弯矩峰值具有滞后效应。

Abstract:

In order to study the structural behavior of reinforced concrete beam-column joints and the changing rules of the constraints between them at elevated temperatures， thermal-load coupling tests on reinforced concrete frame beams were conducted. Based on the test， the VULCAN program is adopted to conduct the numerical analysis of the fire response of the frame beam subjected to high temperature alone， the beam-column subjected to high temperature at the same time， and the beam-column joint moment-rotation relationship at a constant load. The results show that the end restraint strength of reinforced concrete frame beams decreases with the increase of temperature. The peak value of the rotational angle at the beam-column joint has a certain delay compared to the peak value of the restraint moment.