纤维轻骨料混凝土火灾高温后弯曲性能试验研究  

Experimental study on flexural toughness of fiber reinforced concrete with lightweight aggregate after high temperature of fire

作　　者：尤志国 周云龙 杨志年 张宏强 You Zhiguo;Zhou Yunlong;Yang Zhinian;Zhang Hongqiang(Suzhou City University,Suzhou Jiangsu 215104,China;Civil and Architectural Engineering,North China University of Science and Technology,Tangshan Hebei 063210,China;Hebei Key Laboratory of Earthquake Engineering and Disaster Prevention,North China University of Science and Technology,Tangshan Hebei 063210,China;Jidong Oilfield Exploration and Development Construction Supervision Center,Tangshan Hebei 063004,China)

机构地区：[1]苏州城市学院,江苏苏州215104 [2]华北理工大学建筑工程学院,河北唐山063210 [3]华北理工大学河北省地震工程与防灾重点实验室,河北唐山063210 [4]冀东油田勘探开发建设监督中心,河北唐山063004

出　　处：《消防科学与技术》2025年第4期476-484,共9页Fire Science and Technology

基　　金：河北省自然科学基金项目(E2021209121,E2021209112);河北省教育厅科技重点项目(ZD2020139);唐山市科技局应用基础研究项目(21130222C);苏州城市学院科研启动基金(5010702824)。

摘　　要：为研究火灾高温后纤维轻骨料混凝土弯曲性能问题,掺入陶瓷纤维、镀铜钢纤维和陶瓷-镀铜钢纤维配置轻骨料混凝土,制作了尺寸为100 mm×100 mm×400 mm试块15组,按照国际标准ISO-834升温曲线进行20、30、60 min的明火升温试验,采用四点弯曲试验方法进行高温后弯曲试验研究。分析了不同受火时间下纤维种类、纤维掺量对纤维轻骨料混凝土内部温度、荷载-挠度曲线和抗弯强度的影响,基于CECS 13:2009研究高温后纤维对轻骨料混凝土弯曲性能的影响。研究结果表明:在升温滞后平台之前,镀铜钢纤维掺量越大,轻骨料混凝土内部升温越快,陶瓷纤维掺量越大,内部升温越慢;火灾高温后,镀铜钢纤维掺量越大,极限抗弯强度越大,弯曲韧性越好,镀铜钢纤维在改善高温后轻骨料混凝土弯曲性能效果较好;受火60 min后,镀铜钢纤维掺量相同时,陶瓷纤维掺量越高弯曲韧性越好,相对于单掺镀铜钢纤维D50抗弯强度,混掺陶瓷-镀铜钢纤维D50T13抗弯强度降低了43.6%,D50T26、D50T39抗弯强度分别提高了6.39%、24.40%。In order to study the flexural toughness of fiber reinforced concrete with lightweight aggregate after high temperature of fire,the concrete with lightweight aggregate was prepared by adding ceramic fiber,copper-plated steel fiber and ceramic-copper-plated steel fiber.15 groups of 100 mm×100 mm×400 mm test blocks were subjected to open fire temperature rise test for 20 min,30 min and 60 min according to the international standard ISO-834 temperature rise curve.The four point bending test method was used to conduct the bending test after high temperature.The influence of fiber type and fiber content on the internal temperature,load deflec‐tion curve,and bending strength fiber reinforced concrete with lightweight aggregate under different fire time are analyzed.Based on CECS 13:2009,the influence of fiber on the bending toughness of concrete with light‐weight aggregate after high temperature is studied.The results show that before the temperature rise lag plat‐form,the higher the content of copper-plated steel fiber,the faster the internal temperature rise of concrete with lightweight aggregate,and the higher the content of ceramic fiber,the slower the internal temperature rise.After high temperature of fire,the greater the content of copper-plated steel fiber,the greater the ultimate bending strength and the better the bending toughness.Copper-plated steel fiber has a better effect on improving the bending toughness of concrete with lightweight aggregate after high temperature.After being fired for 60 min,with the same content of copper-plated steel fiber,the higher the ceramic fiber content,the better the bending toughness.Compared with the bending strength of the single copper-plated steel fiber of D50,the bending strength of the mixed ceramic copper-plated steel fiber D50T13 decreases by 43.6%,and the bending strength of D50T26 and D50T39 increases by 6.39%and 24.40%.

关 键 词：轻骨料混凝土 火灾高温后 弯曲性能 镀铜钢纤维 陶瓷纤维 

分 类 号：TU528[建筑科学—建筑技术科学] TK121[动力工程及工程热物理—工程热物理]