施工高温作用后CFRP板增强箱梁桥顶板界面有限元分析

发布时间：2018-01-26 12:59

本文关键词： 桥梁工程结构增强有限元 CFRP板界面单元混凝土施工高温 SMA MSC.MARC　出处：《公路交通科技》2017年07期 　论文类型：期刊论文

【摘要】：为了研究SMA(沥青玛蹄脂)摊铺高温作用后CFRP板-混凝土界面剥离破坏,采用SMA摊铺的高温作用后的界面有限单元进行剥离破坏准则定义和回归分析。借助大型通用有限元软件MSC.MARC调用界面有限单元并对CFRP板箱梁桥顶板进行有限元模拟。通过有限元分析可以看出:当荷载值比较小时,CFRP板-混凝土界面未产生裂缝,CFRP板与混凝土间黏结性能较好,沿着梁跨中至梁端方向,CFRP板应变值呈递减趋势。随着荷载值增大,在试验梁跨中位置附近,CFRP板-混凝土界面层出现初始剥离,在界面层剥离区域,CFRP板应变值曲线斜率明显下降,CFRP板应变曲线形状近似S形。随着荷载值增加,在剥离区长度范围内,CFRP板S形应变值沿自由端方向扩展逐渐增大,初始剥离一旦开始,荷载值随之骤然下降;在剥离区域,CFRP板应变值维持恒值不变。研究表明:通过定义SMA摊铺高温作用后CFRP板-混凝土界面单元,引入双重剥离破坏准则,CFRP板-混凝土的界面受剪可通过恒定的裂面剪力传递系数来描述,根据箍筋量配置的不同来描述开裂后混凝土受剪行为,混凝土的开裂形态借助开裂应力描述,受拉软化形态借助软化模量描述,较好地模拟了特殊环境下的CFRP板-混凝土界面的剥离破坏过程。
[Abstract]:In order to study the debonding failure of CFRP slab-concrete interface after the spread of CFRP at high temperature. The interface finite element with SMA spreading is used to define the peeling failure criterion and regression analysis. The interface finite element is called by MSC.MARC and the CFRP plate is obtained by means of the large universal finite element software MSC.MARC. Through the finite element analysis, it can be seen that:. When the load value is small. There is no crack in the interface between CFRP slab and concrete. The strain value of CFRP slab decreases along the direction of mid-beam span to the end of beam, and increases with the increase of load value. The initial delamination of CFRP plate-concrete interface layer occurs near the mid-span of the test beam, and the slope of strain value curve of CFRP plate decreases obviously in the interface layer peeling area. The shape of strain curve of CFRP plate is similar to that of S shape. With the increase of load value, the strain value of CFRP plate increases gradually along the free end direction in the range of peeling zone, and the initial peeling begins. The load value decreases suddenly; The strain value of SMA slab remains constant in the peeling area. The study shows that the double peeling failure criterion is introduced by defining the CFRP plate-concrete interface element after SMA spreading at high temperature. The interface shear of CFRP slab-concrete can be described by constant shear transfer coefficient of crack plane, and the shear behavior of cracked concrete can be described according to the different configuration of stirrups. The crack form of concrete is described by means of crack stress, and the tensile softening form is described by means of softening modulus. The process of debonding and failure of CFRP slab-concrete interface under special environment is well simulated.
【作者单位】：苏州科技大学土木工程学院;东南大学土木工程学院;苏州中固建筑科技有限公司;达卡工程技术大学土木工程学院;
【基金】：国家自然科学基金项目(51508368) 国家高技术研究发展计划(八六三计划)项目(2012AA03A204) 江苏省省建设厅科技计划项目(2015ZD78) 江苏省结构工程重点实验室开放课题项目(ZD1401)
【分类号】：U445.72
【正文快照】： 0引言近些年来,在土木工程加固领域,随着加固方面新材料的出现,自然对加固理论与加固技术也提出更新更高的要求,其中在加固新材料中,碳纤维增强聚合物(carbon fiber reinforced polymer,CFRP)用于土木工程结构加固是一项十分有优势的加固材料。与以往传统加固材料相比,CFRP具

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