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Reforço e reabilitação de estruturas de betão usando materiais compósitos de "CFRP"
| Content Provider | Semantic Scholar |
|---|---|
| Author | Juvandes, Luís Filipe Pereira |
| Copyright Year | 1999 |
| Abstract | This present work refers to the study of bend strengthening of reinforced concrete elements through bonding of advanced materials such as unidirecional Carbon Fiber Reinforced Polymer (CFRP), with the use of an epoxy adhesive. A research programme was carried out to develop this strengthening technology for retrofit or rehabilitation of concrete structures such as buildings and bridges. This programme was based on bending tests of scale-reduced beams and slab strips previously strengthened with CFRP. The first part of this work includes the state-of-art concerning FRP composites. Some aspects are more emphasised, such as the history of bonding with external reinforcement for strengthening of concrete structures, particularly the behaviour of reinforced structures by bonding of unidirectional CFRP composites. Issues such as modes of failure and the behaviour of bond between concrete, adhesive and composite were characterised. A second part describes experimental research developed at the Structures Laboratory of the “Faculdade de Engenharia da Universidade do Porto ( DECivil FEUP)”. This part is divided into two phases. The first phase consists of the description of tests carried out on three series of beams previously flexure strengthened by bonding ready-to-use carbon laminates (CarboDur S 512). Other than faileur mechanisms, various aspects that influence the structural behaviour were considered for each beam series, such as the anchorage length, the type of surface preparation, the bond stress distribution at the concrete-composite interface and the degree of concrete deterioration. The following phase deals with the assessment of the strengthening of scale-reduced slab strips with two different unidirectional CFRP systems regarding its efficiency. These systems consist of the ready-to-use laminates ( CarboDur S 512) and the prepreg sheet (Replark 20). The studies described in this phase led to a joint R & D project with the “Junta Autónoma das Estradas (J. A. E.)”, to assess the applicability of these systems for strengthening the top slab of the ”Nossa Senhora da Guia“ bridge at “Ponte de Lima” city. A further study comprised a thorough investigation into adhesion at the interface composite-adhesive-concrete. Different surface treatments were considered such as preparation with a needle hammer, sand paper and sand blasting followed or not by further application of a primary. Pull-off tests were carried out on beams, on slab strips and on concrete prismatic specimens with the different surface treatments. Finally, conclusions are drawn out and recommendations concerning the bonding technique for CFRP systems are presented. Work to be developed in the future is also suggested. |
| File Format | PDF HTM / HTML |
| Alternate Webpage(s) | https://repositorio-aberto.up.pt/bitstream/10216/11552/2/Texto%20integral.pdf |
| Language | English |
| Access Restriction | Open |
| Content Type | Text |
| Resource Type | Article |
