摘要
为研究纤维混凝土高温损伤行为,开展不同温度下混杂纤维混凝土(PVA纤维和玄武岩纤维)的声学特性试验,并结合电镜扫描SEM结果从微观层面进行机理解释。结果表明,随温度不断攀升,超声波波形畸变程度越显著,波形幅值衰减逐渐加剧;掺入纤维和温度升高均会导致波形主频幅值降低,加剧超声波穿透试件引起的能量耗散。高温下,PVA纤维熔化后残留大量孔道,并逐渐形成连通孔,促进孔隙蒸气压力的释放,缓解高温损伤,而玄武岩纤维继续发挥桥连效应,抑制高温裂纹的不断发展。
In order to study the damage behavior of fiber reinforced concrete at high temperature,the acoustic characteristics of hybrid fiber reinforced concrete(PVA fiber and basalt fiber)at different temperatures were tested,and the mechanism was explained from the microscopic level by combining the results of the SEM.The results show that with the rising of temperature,the degree of ultrasonic waveform distortion is more significant,and the attenuation of waveform amplitude is gradually intensified;The incorporation of fiber or the increase of temperature will reduce the amplitude of the dominant frequency of the waveform and increase the energy dissipation caused by the ultrasonic penetration of the specimen.At high temperature,after PVA fiber is melted,a large number of pores remain and gradually form connecting pores,which promote the release of pore steam pressure and alleviate high-temperature damage,while basalt fiber continues to play a bridging effect to inhibit the continuous development of high-temperature cracks.
作者
朱从香
徐俊
ZHU Cong-xiang;XU Jun(Yangzhou Polytechnic Institute,Yangzhou 225000,China;College of Civil Engineering and Architecture,Jiangsu University of Science and Technology,Zhengjiang 212100,China)
出处
《水电能源科学》
北大核心
2023年第7期184-187,192,共5页
Water Resources and Power
基金
国家自然科学基金项目(52108216)
扬州市装配式建筑技术公共服务平台(YZ2022149)
2021年校级科研项目(2021xjzk015)。
关键词
混杂纤维混凝土
声学特性
高温
损伤行为
蒸汽压力
hybrid fiber concrete
acoustic characteristics
high temperature
damage behavior
steam pressure
