UHPC与石材的粘结界面抗剪性能试验研究  

Experimental Research on the Shear Property of Interfacial Bonding Between UHPC and Stone

作　　者：马兴林 杨俊[1,2,3] 周建庭 王劼耘[3] 张中亚 苏昊 王宗山 MA Xinglin;YANG Jun;ZHOU Jianting;WANG Jieyun;ZHANG Zhongya;SU Hao;WANG Zongshan(State Key Laboratory of Mountain and Tunnel Engineering,Chongqing Jiaotong University,Chongqing 400074,China;School of Civil Engineering,Chongqing Jiaotong University,Chongqing 400074,China;Guangxi Communications Investment Group Corporation Ltd.,Nanning 530022,China)

机构地区：[1]重庆交通大学山区桥梁及隧道工程国家重点实验室,重庆400074 [2]重庆交通大学土木工程学院,重庆400074 [3]广西交通投资集团有限公司,南宁530022

出　　处：《材料导报》2022年第24期90-96,共7页Materials Reports

基　　金：国家自然科学基金青年基金(51908093);重庆市自然科学基金(cstc2020jcyj-msxmX0088,cstc2020jcyj-bshX0007);湖北省交通运输厅科技项目(2020-2-1-1,2020-186-1-6);重庆市教委科技青年项目(KJQN201900733);中国博士后科学基金(2021M693919);重庆交通大学研究生科研创新基金(2020B0004)。

摘　　要：由于荷载等级提高、超重超载车辆增多、圬工材料风化剥落等诸多原因,大量在役石拱桥面临性能退化问题,因此,提出采用UHPC对石拱桥进行维修加固的新技术。为明晰UHPC与石材界面的粘结性能,从贵州某服役30年石拱桥位处选取原位石料,设计四组直剪试验构件,分别为单排植筋(ZJ1)、双排植筋(ZJ2)、单排植筋蒸养(ZJ3)、凿毛(ZM),考察不同界面粘结方式对UHPC-石材抗剪性能的影响。结果表明:UHPC与石材的粘结界面抗剪强度高,承载潜力大,通过界面植筋处理,最大可将构件的延性提升17倍;单纯采用凿毛处理的UHPC-石材试件,界面处是构件剪切破坏的薄弱面,而增加植筋的构件以石材劈裂破坏为主;界面植筋率提升100%后,可将界面极限抗剪承载能力提升392%;UHPC的蒸汽养护对构件的界面抗剪承载能力存在负面影响,导致其抗剪承载力降低0.4 MPa;分析加载过程中的应力传递规律,可为同类型的优化加固提出两点建议,一是通过植筋作用保证界面均匀协同受力,二是考虑在靠近加载侧部位进行加强配置以优化结构受力。最后,推导了UHPC-石材植筋界面剪切承载能力计算公式,结果表明可忽略植入钢筋的摩擦抗剪作用对界面粘结强度的贡献。Due to the increase of load level,overweight vehicles,and peeling of masonry materials,many stone arch bridges in service is facing the problem of performance degradation.A new technology of using UHPC to repair and strengthen the stone arch bridges is proposed.In order to clarify the bonding performance of UHPC and stone interface,four groups of direct shear test components were designed while stones were selected from a stone arch bridge sited in Guizhou for 30 years,including single row planting reinforcement(ZJ1),double row planting reinforcement(ZJ2),single row planting reinforcement with steam curing(ZJ3),roughening(ZM).The effects of different bonding modes on the shear resistance of UHPC masonry stone were investigated.Results show that:the shear strength and bearing potential of the bonding interface between UHPC and stone are high.The ductility of the components can increase 17 times by the treatment of reinforcement;the interface of UHPC-stone specimen treated by chipping is the weak point of shear failure while the component with bars mainly broke as stone splitting;when the reinforcement planting rate of the interface is increased by 100%,the ultimate shear capacity of the interface can be increased by 392%;the steam maintenance of UHPC has a negative effect on the shear capacity of the interface,which leads to the reduction of shear capacity by 0.4 MPa;two suggestions can be put forward for the same type of optimization reinforcement by analyzing the stress transfer law in the loading process.One is to ensure the uniform and collaborative force of the interface by planting reinforcement,and the other is to consider strengthening configuration near the loading side to optimize the structural stress.Finally,the calculation formula of shear capacity of UHPC stone planting reinforcement interface is derived.The results show that the contribution of anchor bar deformation to the bond strength of the interface can be ignored.

关 键 词：桥梁加固 直剪试验 超高性能混凝土(UHPC) 石材 

分 类 号：U448.22[建筑科学—桥梁与隧道工程]