建筑隔震橡胶支座的耐火性能试验

摘要

The paper presents an experimental study of fire resistance of four lead rubber bearings and two natural rubber bearings with a diameter of 600mm under the ISO834 standard heating process. The influences of fire duration and vertical load on the residual mcchanical properties of rubber bearings after fire are investigated. Test results show that： a） the integrity and vertical load bearing capacity of rubber bearings failed completely ＂after exposure to fire for about 1.5 hours; b） the mechanical properties of rubber bearings after exposure to fire for 0.5 hour tended to deteriorate within 10%, and the horizontal deformation capacity can still meet the requirements of Chinese design codes; within the usual range of vertical compressive stress for rubber bearings, the effect of vertical load on residual mechanical properties of rubber bearings after 0.5 hour fire was limited ; and c） the mechanical properties of rubber bearings after exposure to fire for 1.0 hour exhibited significant degradation. Because the fire resistance of seismic rubber bearings is poor, it is necessary to add fire insulation to the bearings.%在IS0834标准升温条件下，开展直径600mm的4个铅芯隔震橡胶支J坐和2个无铅芯隔震橡胶支座的叫火试验，考察受火时间和竖向荷载对受火后支座剩余力学性能的影响。试验结果表明：①受火1．5h左右，支鹰的整体性和承载能力完全丧失；②受火0．5h后，支座力学性能的改变幅度小于10％．且其水平极限变形能力仍可满足使用要求，同时在竖向压应力常用取值范围内，竖向荷载对支座受火后的剩余力学性能影响有限；③受火1．Oh后，支座力学性能明屁劣化。由于隔震橡胶支座的耐火能力不足，实际工程中应在支座处设置防火保护。