Comparative fire behavior of reinforced RPC and NSC simply supported beams
Comparative fire behavior of reinforced RPC and NSC simply supported beams
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钢筋 RPC 和 NSC 简支梁的防火性能比较
DOI：
10.1016/j.engstruct.2019.01.097
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发表时间：
2019-04-15
影响因子：
5.5
通讯作者：
Zhan, Yao
中科院分区：
文献类型：
--
作者：
Hou, Xiaomeng;Ren, Pengfei;Zhan, Yao
目前对活性粉末混凝土（RPC）的高温性能研究主要集中在材料层面，对RPC梁的耐火性能研究相对较少。因此，进行了试验研究，以探讨四个钢筋RPC简支梁的行为暴露在三个方面的火灾。文中给出了不同高度的截面温度、跨中挠度、轴向热膨胀、裂缝形态、破坏模式和梁的耐火极限等试验结果。从测试中获得的数据也被用来评估的RPC覆盖层厚度，负载水平和纤维含量，RPC梁的热响应和结构响应的重要参数，如效果。结果表明，在火灾过程中，在室温下，RPC梁的钢筋不足，可能会破坏轻钢筋梁。RPC保护层厚度和荷载水平对加固RPC简支梁的抗火性能有显著影响。在钢筋混凝土梁中掺入2%的钢纤维和0.2%的聚丙烯纤维是防止钢筋混凝土梁火灾剥落的有效方法。在此基础上，通过对RPC梁的试验研究以及对RPC梁和普通强度混凝土梁的数值模拟研究，分析了RPC梁和普通强度混凝土梁耐火性能的差异。结果表明，在相同的室温抗弯承载力下，NSC梁的抗火性能优于RPC梁。
The behavior of reactive powder concrete (RPC) at high temperatures has been mainly studied at the material level, and relatively few experimental studies have been conducted on the fire performance of RPC beams. An experimental investigation was therefore undertaken to explore the behavior of four reinforced RPC simply supported beams exposed to fire on three sides. The results such as cross-section temperatures at different heights, mid-span deflections, axial thermal expansion, crack patterns, failure modes, and fire resistance of beams are presented in this paper. The data obtained from the tests were also used to evaluate the effects of significant parameters such as RPC cover thickness, load level and fiber content, on the thermal and structural response of RPC beams. The results show that during fire, RPC beams that are under-reinforced at room temperature may fail as the lightly reinforced beams. Both RPC cover thickness and load level significantly affect the fire behavior of reinforced RPC simply supported beams. The addition of 2% steel fibers and 0.2% polypropylene fibers is an effective method to prevent the fire induced spalling of the reinforced RPC beams. Furthermore, based on the experimental studies on RPC beams and the numerical studies on RPC beams and normal strength concrete (NSC) beams, the difference in the fire resistance performance between RPC beams and NSC beams was investigated. It is shown that under the same flexural capacity at room temperature, the NSC beams exhibit a better fire resistance performance than the RPC beams.