基于有限元法的外贴FRP加固结构分析研究

发布时间：2018-06-27 01:23

本文选题：FRP + 内聚力区模型　；参考：《浙江大学》2014年硕士论文

【摘要】：本文根据外贴FRP结构的形状和受力特点,提出了一种新型的外贴FRP梁单元和外贴FRP板单元。外贴FRP梁单元能够用于分析外贴FRP梁端部剥离和由于弯曲裂缝引起的中部剥离。该梁单元主要用于分析粘结层破坏引起的FRP剥离,因此在分析中假设FRP和混凝土梁始终处于线弹性状态,而粘结层采用内聚力区模型。由于粘结层很薄,因此假设粘结层内剪应变沿粘结层厚度均匀分布,在此基础上,导出了粘结层处于弹性、软化和剥离等各个阶段时该梁单元的刚度矩阵。同时将梁体弯曲裂缝模拟为弹簧铰,得到了带裂缝的表面粘贴FRP梁单元的刚度矩阵显式表达式.然后在板理论和线弹性假设基础上,推导出了外贴FRP板单元刚度矩阵表达式。最后通过若干算例与已有结果进行对比,并计算模拟了多条裂缝和多个荷载情况下的中部剥离过程以及线弹性条件下外贴FRP板的粘结剪应力分布情况,验证了本文单元的实用性、精确性和便捷性。
[Abstract]:In this paper, a new type of FRP beam element and external FRP plate element are proposed according to the shape and mechanical characteristics of the externally attached FRP structure. The externally bonded FRP beam element can be used to analyze the exfoliation of the end part of the externally bonded FRP beam and the central exfoliation caused by the bending crack. The beam element is mainly used to analyze the FRP peel caused by bond layer failure, so it is assumed that the FRP and concrete beams are always in a linear elastic state, while the cohesive zone model is used in the bond layer. Because the bond layer is very thin, it is assumed that the shear strain in the bond layer is uniformly distributed along the thickness of the bond layer. On this basis, the stiffness matrix of the beam element is derived when the bond layer is in the elastic, softening and peeling stages. At the same time, the bending crack of the beam is simulated as a spring hinge, and the explicit expression of the stiffness matrix of the FRP beam element with cracks is obtained. Then, based on the theory of plate and the assumption of linear elasticity, the stiffness matrix expression of external FRP plate element is derived. Finally, some examples are compared with the existing results, and the central peel process under multiple cracks and loads and the bond shear stress distribution of FRP plates are simulated under linear elastic conditions. The practicability, accuracy and convenience of the unit are verified.
【学位授予单位】：浙江大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U445.72

【参考文献】