Derkowski Wit, Walczak Rafał
Department for Building Technology, Linnaeus University, SE-351 95 Växjö, Sweden.
Chair for RC and RC Structures, Faculty of Civil Engineering, Cracow University of Technology, 31-155 Cracow, Poland.
Materials (Basel). 2021 Mar 12;14(6):1387. doi: 10.3390/ma14061387.
Modern composite materials based on non-metallic continuous fibres are increasingly used in civil engineering to strengthen building structures. In the strengthening of reinforced concrete (RC) structures, the utilisation of externally bonded fibre-reinforced polymer (FRP) composites is only up to 35% because of the pilling-off failure mechanism. This problem can be solved using pre-tensioned composite laminates. Due to more complex behaviour, the strengthening of structures by means of prestressing technology needs a careful design approach and a full understanding of the behaviour of both the materials and elements. The advantages and risks of the presented technology, which may determine the success of the entire project, will be highlighted in the paper. The possibility of using a flexible adhesive layer in carbon fibre reinforced polymer (CFRP) strengthening applications for flexural strengthening of RC elements, as an innovative solution in civil engineering, will also be presented. Parallel introduction of the flexible adhesive layer (made of polyurethane masses) and a traditional epoxy adhesive layer in one strengthening system was investigated in the laboratory tests. This solution was used for the repair and protection of a previously damaged RC beam against brittle failure.
基于非金属连续纤维的现代复合材料在土木工程中越来越多地用于加强建筑结构。在钢筋混凝土（RC）结构的加固中，由于剥离破坏机制，外部粘结纤维增强聚合物（FRP）复合材料的利用率仅为35%。这个问题可以通过使用预张紧复合层压板来解决。由于行为更为复杂，采用预应力技术加固结构需要谨慎的设计方法，并充分了解材料和构件的性能。本文将重点介绍所提出技术的优点和风险，这些优点和风险可能决定整个项目的成败。作为土木工程中的一种创新解决方案，还将介绍在碳纤维增强聚合物（CFRP）加固应用中使用柔性粘结层对RC构件进行抗弯加固的可能性。在实验室试验中研究了在一个加固系统中同时引入柔性粘结层（由聚氨酯材料制成）和传统环氧粘结层的情况。该解决方案用于修复和保护先前受损的RC梁，防止其发生脆性破坏。
