基于声发射技术的UHPC-NC组合梁延性研究  

Research on the Ductility of UHPC-NC Concrete Composite Beams based on Acoustic Emission Technology

作　　者：郑永飞 刘常振 解路 郭攀[4] 邓恩峰 ZHENG Yongfei;LIU Changzhen;XIE Lu;GUO Pan;DENG Enfeng(CCCC Fourth Highway First Engineering Co.,Ltd.,Beijing 100123,China;CCCC Construction Group Co.,Ltd.,Beijing 100000,China;School of Civil Engineering,Zhengzhou University,Zhengzhou 450000 China;Collage of Water Conservancy and Transportation,Zhengzhou University,Zhengzhou 450000 China)

机构地区：[1]中交四公局第一工程有限公司,北京100123 [2]中交建筑集团有限公司,北京100000 [3]郑州大学土木工程学院,河南郑州450000 [4]郑州大学水利与交通学院,河南郑州450000

出　　处：《粉煤灰综合利用》2024年第5期149-154,共6页Fly Ash Comprehensive Utilization

基　　金：河南省交通运输厅科技项目(2021J3)。

摘　　要：UHPC-NC组合梁延性的检测方法较为单一,且对梁体的开裂损伤缺少有效的监测手段。文章分别对NC梁和UHPC-NC组合梁进行四点弯曲试验,采用声发射技术对破坏过程进行监测,并基于声发射累计振铃计数和能量对其进行延性分析。结果表明:相较于NC梁,采用50 mm厚UHPC的UHPC-NC组合梁在开裂荷载、屈服荷载和极限荷载方面均有所提高,对开裂荷载的提升效果最大,达到100%,然而,其位移延性和曲率延性分别降低了7.0%和10.0%;在受弯破坏过程中,UHPC-NC组合梁将NC梁的开裂荷载阶段从极限荷载的14.0%延续至25.0%;通过声发射的累计振铃计数和能量分析,证明了这种方法在混凝土结构延性指数计算中的可行性。The detection methods for the ductility of UHPC-NC composite beams are relatively singular,and effective monitoring techniques for crack damage in the beams are lacking.This paper conducts four-point bending tests on both NC beams and UHPC-NC composite beams,employing acoustic emission technology to monitor the failure process and performing ductility analysis based on the cumulative ringing count and energy of acoustic emissions.The results indicate that,compared to NC beams,the UHPC-NC composite beam with a 50mm thick UHPC layer exhibits improvements in cracking load,yield load,and ultimate load,with the greatest enhancement observed in the cracking load,which increased by 100%.However,the displacement ductility and curvature ductility decreased by 7.0%and 10.0%,respectively.Additionally,during the bending failure process,the UHPC-NC composite beam extended the cracking load phase of the NC beam from 14.0%to 25.0%of the ultimate load.Through the analysis of cumulative ringing count and energy from acoustic emissions,this study demonstrates the feasibility of this method for calculating the ductility index of concrete structures.

关 键 词：UHPC-NC组合梁 混凝土梁 受弯试验 延性 声发射 参数特征 

分 类 号：TU375[建筑科学—结构工程]