高温后陶瓷纤维增强地聚物混凝土性能与声学损伤的关系  

Relationship between properties and ultrasonic damaged characteristics of ceramic fiber reinforced geopolymeric concrete after heating at elevated temperatures

作　　者：任韦波[1] 许金余[1,2] 白二雷[1] 苏灏扬[1] 

机构地区：[1]空军工程大学机场建筑工程系,陕西西安710038 [2]西北工业大学力学与土木建筑学院,陕西西安710072

出　　处：《材料热处理学报》2014年第3期13-19,共7页Transactions of Materials and Heat Treatment

基　　金：国家自然科学基金资助项目(51078350);国家自然科学基金资助项目(51208507)

摘　　要：以矿渣和粉煤灰为原料,制备了陶瓷纤维增强地质聚合物混凝土(CFRGC)。通过抗压强度试验、超声波测试和裂缝宽度检测,引入小波变换理论,研究了不同温度、不同纤维掺量下CFRGC强度、波速、频谱特征的变化规律以及温度裂缝的开展演化情况。结果表明,高温后CFRGC内部结构受损,导致抗压强度降低,纵波波速和声阻抗减小,温度裂缝宽度增大;声波测试信号经小波分解后在各频段内的功率谱密度分布及能量随损伤的增大有较为明显的变化,某一频段内的信号能量对损伤比波速更敏感;纤维体积掺量为0.3%时,陶瓷纤维对地质聚合物混凝土的高温性能具有良好的改善效果。Slag and fly ash were used to produce ceramic fiber reinforced geopolymeric concrete （CFRGC）. The CFRGC materials with different volumetric fractions of ceramic fiber after heating at different temperatures, the change of compressive strength, longitudinal wave velocity and frequency spectrum characteristics of CFRGC, as well as the evolution of temperature crack, were studied by compressive strength testing, ultrasonic testing, crack width observation and wavelet transform analysis. The results indicate that the strength, wave velocity and wave impedance of CFRGC decrease and temperature crack width increases after high-temperature exposure. The distribution of power spectral density and signal energy in each wave band has evident changes with the rising thermal damage after wavelet decomposition. Signal energy in one wave band is more sensitive to the damage than longitudinal wave velocity. The addition of ceramic fiber significantly improves the high-temperature properties of CFRGC when the volumetric fraction of ceramic fiber is 0.3%.

关 键 词：地质聚合物混凝土 陶瓷纤维 高温 超声波检测 小波变换 

分 类 号：TB321[一般工业技术—材料科学与工程]