基于内聚力本构模型的UHPC湿接缝界面性能  

Study on Interface Properties of UHPC Wet Seams Based on Cohesive Constitutive Model

作　　者：肖桂元[1] 刘鹏程 何静 XIAO Guiyuan;LIU Pengcheng;HE Jing(College of Civil Engineering and Architecture,Guilin University of Technology,Guilin,541000,China;School of Civil Engineering,Hunan University,Changsha 410000,China)

机构地区：[1]桂林理工大学土木与建筑工程学院,广西桂林541000 [2]湖南大学土木工程学院,湖南长沙410000

出　　处：《洛阳理工学院学报（自然科学版）》2023年第4期36-44,共9页Journal of Luoyang Institute of Science and Technology：Natural Science Edition

基　　金：国家自然科学基金项目(11202128).

摘　　要：针对大节段预制拼装超高性能混凝土(UHPC)梁湿接缝受力复杂、易开裂等问题,通过轴拉与弯拉试验,研究了不同接缝形式、不同浇筑方式下对UHPC湿接缝界面开裂荷载、峰值荷载、伸长量、接缝单元抗拉强度的影响规律。基于试验数值建立有限元模型,分析了不同湿接缝接触形式下荷载位移曲线和接缝处钢筋应变的拟合情况。湿润的接缝界面相较于干燥的接缝界面,轴拉和弯拉强度都提升了10%;对于配筋接缝界面,钢筋的约束作用及UHPC的收缩极大地削弱接缝界面的粘结性能;采用内聚力本构模型所得到的试验板荷载挠度曲线在弹性段与试验值更为接近,对于接缝处凿毛效果较差的试验板在采用内聚力加摩擦的界面接触形式可以较好地模拟出混凝土与钢筋的变形协调关系。Aiming at the problems of complex stress and easy cracking of wet joints of large-segment prefabricated UHPC beams,the influence of UHPC wet joint interface cracking load,peak load,elongation and tensile strength of joint element under different joint forms and different pouring methods was studied through shaft tension and bending pull specimen tests.Based on the test values,the finite element simulation parameters were established,and the fit of the load displacement curve and the strain of the steel bar at the joint under different wet joint contact forms was analyzed.The results show that,compared with the dry seam interface,the shaft tension or bending tension strength of the wet joint interface is increased by 10%.For the reinforcement joint interface,due to the restraining effect of the steel bar and the shrinkage of UHPC,the bonding performance of the joint interface will be greatly weakened.The load deflection curve of the bread board obtained by using the cohesive constitutive model is closer to the experimental value in the elastic section,and the deformation coordination relationship between concrete and steel bar can be better simulated in the form of interfacial contact with cohesion and friction for the bread board with poor gouging effect at the joint.

关 键 词：UHPC 接缝 有限元模拟 

分 类 号：TU444[建筑科学—岩土工程]