碳纤维布加固高强砂浆动态压缩试验研究  

Experimental Study on Dynamic Compression of High-strength Mortar Reinforced by CFRP

作　　者：吕闹 汪海波[1] 宗琦[1] LYU Nao;WANG Haibo;ZONG Qi(School of Civil Engineering and Architecture,Anhui University of Science&Technology,Huainan 232001,Anhui,China)

机构地区：[1]安徽理工大学土木建筑学院,安徽淮南232001

出　　处：《材料导报》2022年第10期59-64,共6页Materials Reports

基　　金：安徽省自然科学基金(2008085ME163)。

摘　　要：为了研究碳纤维布(CFRP)加固后砂浆的动态强度和破碎特征,利用直径50 mm分离式Hopkinson试验装置开展不同冲击气压下普通砂浆和CFRP加固砂浆的动态压缩试验。基于孕育时间准则,分析了砂浆试件的应力率灵敏性以及瞬时峰值强度的增大趋势。结果表明:在试验的应力率范围内,普通砂浆和CFRP加固砂浆的峰值应力均随着应力率的增加而增加,而临界时间呈缩短趋势,CFRP加固砂浆的临界时间相比于普通砂浆要滞后9~61.7μs,且应力率越大,临界时间滞后的幅度越小;普通砂浆和CFRP加固砂浆的孕育时间分别为54.2μs和72.1μs,不同的孕育时间表明它们的应力的动态增长效应不同,CFRP加固砂浆的应力的动态增长效应大于普通砂浆;CFRP加固砂浆试件出现分层断裂现象,随着应力率的增大,CFRP加固砂浆的破碎特征逐步接近普通砂浆。To study the dynamic strength and fracture characteristics of CFRP reinforced mortars,dynamic compression tests of normal mortars and CFRP reinforced mortars under different velocities were performed with the 50 mm split Hopkinson bar system.The incubation time criterion acted as a standard to analyze stress rate sensitivity and the increase trend of the instantaneous critical strength of mortar specimens.The results show that,within the range of the tested stress rate,the tested dynamic strengths of normal mortars and CFRP reinforced mortars increases with stress rate,while their critical time decreases with it.The critical time of CFRP reinforced mortar lags 9—61.7μs,compared with that of normal mortar,and the greater the stress rate is,the smaller the extent of the critical time lag is.The incubation time of normal mortars and CFRP reinforced mortars are 54.2μs and 72.1μs respectively,indicating that their dynamic enhancement effects of stress are different,and the dynamic enhancement effect of CFRP reinforced mortars is more significant than that of normal mortars.The layered fracture of CFRP reinforced mortar spe-cimens appears,and with the increase of stress rate,the fracture characteristics of CFRP reinforced mortar specimens are gradually close to that of ordinary mortar.

关 键 词：碳纤维布 动态压缩 应力率 破碎特征 孕育时间 

分 类 号：TU528[建筑科学—建筑技术科学]