工程结构中的受弯钢梁由于腐蚀或疲劳损伤需要进行加固和修复,与传统的钢结构加固方法相比,粘贴CFRP加固钢结构具有很大的优势和应用前景,如不会导致严重的应力集中、不会产生残余应力、施工方便、维护费用低等,但是目前仅对CFRP加固钢梁和组合梁进行了部分试验研究,缺乏相关的有限元分析,对CFRP加固钢梁和组合梁有限元分析的几个关键问题进行了论述,并采用笔者提出的“三维实体-弹簧-壳元”有限元模型对钢梁和组合梁粘贴CFRP加固前、后的性能进行了分析,分析结果表明,损伤钢梁和组合梁粘贴CFRP布和CFRP板加固后其性能恢复非常显著,而且粘贴CFRP板的加固效果更加明显。
A significant number of steel beams are in service and many of them are in urgent need of rehabilitation due to fatigue or corrosion damage. There are several advantages of adhesively bonded carbon fiber reinforced polymer (CFRP) laminates to the deteriorated steel members over traditional retrofit methods, such as without stress concentrations, no residual stress, easy to construct and at low maintenance cost. However, only very limited experimental studies have been conducted on the application of CFRP composites to steel beams and there was hardly any finite element study on steel and steel-concrete composite beams strengthened with CFRP. The details of FE model for steel and steel-concrete composite beams strengthened with CFRP were discussed, and the "3D Solid-Spring-Shell element" FE model presented by the authors was adopted to analyze the behavior of steel and steel-concrete composite beams un-repaired and repaired with CFRP laminates. Results showed that the behavior of the deteriorated steel and steel-concrete composite beams restored effectively, and it was more effective for the beams rehabilitated with CFRP plates.