The use of bonded CFRP laminates to strengthen and upgrade existing structures has attracted a great deal of attention during the past two decades. The superior mechanical properties of CFRP laminates, such as high strength and stiffness, excellent fatigue properties and good durability characteristics, have made them a suitable alternative to steel plates used in traditional strengthening and repair methods. FRP bonding has been widely researched and practised in the strengthening of concrete members. However, when it comes to steel structures, it is somewhat limited in terms of field applications. One of the most important obstacles to the widespread use of FRP bonding in steel structures is the lack of design codes. This is mainly due to the lack of design models for adhesive joints used to bond FRP laminates to steel substrates. Issues such as the lack of knowledge about the behaviour of adhesive joints, the lack of suitable material models for structural adhesives and difficulty analysing adhesive joints are contributing to the difficulty associated with establishing design models.
This project is mainly concerned with a detailed study of adhesive joints used to bond FRP laminates to steel substrates in order to develop a design model. The project includes comprehensive analytical, numerical and experimental work to obtain a good understanding of the behaviour of these adhesive joints. The work focuses on failure initiation and propagation, failure modes and the influence of material properties on the strength of joints. A new design model has been proposed for steel beams bonded with FRP laminates in this project. The advantages offered by the new design model include ease of application, the opportunity to treat different loads and geometries of joints and accuracy of predictions.
The project is carried out at the Division of Structural Engineering, in the research group Steel and Timber Structures.
Related projects is "Long-term performance of adhesive joints in FRP bonded steel members" and "PANTURA"
Keywords: Adhesive joint, FRP, Laminate, Design, Stress concentration