异形阻燃木-混凝土组合梁耐火特性实验*

为提高纯木梁的耐火性能，提出异形阻燃木-混凝土组合梁提高耐火性能的方法。通过实验研究对比Π形、T形的异形阻燃木-混凝土组合梁与全混凝土梁受火特性和剩余承载力。研究结果表明:3面受火后，异形阻燃木-混凝土组合梁上部多数区域未达强度降低起始温度，全混凝土梁均超过强度降低起始温度，且受火温度远远高于木-混凝土组合梁；T形阻燃木-混凝土组合梁试件剩余承载力最大，耐火能力最强，Π形阻燃木-混凝土组合梁次之，全混凝土梁最差；异形阻燃木-混凝土组合梁受火后损坏情况轻于全混凝土梁，但产烟量大于全混凝土梁。

Experiments on fire resistance characteristics of special-shaped flame-retardant wood and concrete composite beam

To improve the fire resistance of pure wooden beams,a method for improving the fire resistance of special-shaped flame-retardant wood and concrete composite beam was proposed.The fire characteristics and residual bearing capacity of Π-shaped and T-shaped special-shaped flame-retardant wood and concrete composite beams and full concrete beam were compared through the experimental research.The results showed that after the fire exposure of three surfaces,most areas at the upper part of the special-shaped flame-retardant wood and concrete composite beam did not reach the initial temperature of strength reduction,while the full concrete beam all exceeded the initial temperature of strength reduction,and the fire temperature was much higher than that of the wood and concrete composite beam.The T-shaped flame-retardant wood and concrete composite beam had the largest residual bearing capacity and the strongest fire resistance,followed by the Π-shaped flame-retardant wood and concrete composite beam,and the full concrete beam was the worst.The damage of special-shaped fire-retardant wood and concrete composite beams after fire were lighter than that of full concrete beam,but the amounts of produced smoke were greater than that of full concrete beam.