The non-corrodible nature of FRP bars along with their high strength, light weight and ease of installation made it attractive as reinforcement especially for structures exposed to aggressive environment. In addition, the transparency of FRP bars to magnetic and electrical fields makes them an ideal alternative to traditional steel reinforcement in applications sensitive to electromagnetic fields such as magnetic resonance imaging (MRI) units. Continuous concrete beams are commonly-used elements in structures such as parking garages and overpasses, which might be exposed to extreme weather conditions and the application of de-icing salts. In such structures, using the non-corrodible FRP bars is a viable alternative to avoid steel-corrosion problems. However, the linear-elastic behaviour of FRP materials makes the ability of continuous beams to redistribute loads and moments questionable. The objective of this research project is to investigate the flexural behaviour of continuous concrete beams reinforced with FRP and their capability of moment redistribution. An experimental program was conducted at the University of Manitoba to realize the research objectives. Ten full-scale continuous concrete beams were constructed and tested to failure in the laboratory. The specimens had a rectangular cross-section of 200×300 mm and continuous over two spans of 2,800 mm each. The main investigated parameters were the amount and material of longitudinal reinforcement, the amount and material of transverse reinforcement and the spacing of used stirrups. The experimental results showed that moment redistribution in FRP-reinforced continuous concrete beams is possible if the reinforcement configuration is chosen properly, and is improved by increasing the amount of transverse reinforcement. A finite element investigation was conducted using ANSYS-software. A 3-D model was created to simulate the behaviour of continuous beams reinforced with FRP. The model was verified against the experimental results obtained from the present study. This verified model was used to investigate the effect of the concrete compressive strength, longitudinal reinforcement ratio, midspan-to-middle support reinforcement ratio and the amount of transverse reinforcement on the behaviour of FRP-reinforced beams. The analytical results of this parametric investigation along with the experimental results were used to propose an allowable limit for moment redistribution in FRP-reinforced continuous concrete beams.

The non-corrodible nature of FRP bars along with their high strength, light weight and ease of installation made it attractive as reinforcement especially for structures exposed to aggressive environment. In addition, the transparency of FRP bars to magnetic and electrical fields makes them an ideal alternative to traditional steel reinforcement in applications sensitive to electromagnetic fields such as magnetic resonance imaging (MRI) units. Continuous concrete beams are commonly-used elements in structures such as parking garages and overpasses, which might be exposed to extreme weather conditions and the application of de-icing salts. In such structures, using the non-corrodible FRP bars is a viable alternative to avoid steel-corrosion problems. However, the linear-elastic behaviour of FRP materials makes the ability of continuous beams to redistribute loads and moments questionable. The objective of this research project is to investigate the flexural behaviour of continuous concrete beams reinforced with FRP and their capability of moment redistribution. An experimental program was conducted at the University of Manitoba to realize the research objectives. Ten full-scale continuous concrete beams were constructed and tested to failure in the laboratory. The specimens had a rectangular cross-section of 200×300 mm and continuous over two spans of 2,800 mm each. The main investigated parameters were the amount and material of longitudinal reinforcement, the amount and material of transverse reinforcement and the spacing of used stirrups. The experimental results showed that moment redistribution in FRP-reinforced continuous concrete beams is possible if the reinforcement configuration is chosen properly, and is improved by increasing the amount of transverse reinforcement. A finite element investigation was conducted using ANSYS-software. A 3-D model was created to simulate the behaviour of continuous beams reinforced with FRP. The model was verified against the experimental results obtained from the present study. This verified model was used to investigate the effect of the concrete compressive strength, longitudinal reinforcement ratio, midspan-to-middle support reinforcement ratio and the amount of transverse reinforcement on the behaviour of FRP-reinforced beams. The analytical results of this parametric investigation along with the experimental results were used to propose an allowable limit for moment redistribution in FRP-reinforced continuous concrete beams.

Les matériaux composites à matrice polymères renforcés aux fibres de carbone (PRFC) sont de plus en plus utilisés dans les avions, en raison de leur faible densité et de leurs propriétés mécaniques comparables aux alliages généralement utilisés. Ils sont cependant sensibles aux impacts répétés des particules solides et liquides intervenant au cours du cycle de vol d’un avion, et nécessitent d’être protégés. Cette thèse est inscrite dans ce contexte de protection des PRFC, plus particulièrement ceux à matrice époxy, par le biais de dépôts anti-usure réalisés par projection plasma sous air. De tels recherche ont été menées auparavant avec pour résultats des dépôts céramique et métallique peu adhérents, sur des composites fortement endommagés par le procédé. Les travaux de cette thèse ont donc été organisés autour de deux objectifs :- Objectif fondamental : comprendre les interactions entre les particules fondues et le composite. Grâce à une étude multiéchelles d’impacts de gouttes sur le composite, la résine époxy et sa dégradation thermique ont été identifiés comme responsable de la mauvaise adhérence des dépôts projetés par plasma sur les PRFC.- Objectif expérimental. Déterminer la faisabilité de réaliser un revêtement anti-usure par projection plasma sur PRFC. Deux traitements de surface avant dépôt ont été choisis puis testés, en conditions d’impacts de particules isolées et de formation de dépôts. Des dépôts d’alumine ont pu être obtenus, sans dégradation thermique ou mécanique du composite. / Carbon fiber reinforced polymers (CFRP) are increasingly used in aircraft structures, due to their good strength to weight ratio. However, they are more sensitive to the impacts of solid and liquid particles, occurring during the aircraft flight cycle, and thus need to be protected. This work focuses on the protection of carbon fiber reinforced epoxy by air plasma spraying (APS). Numerous studies have been conducted on applying such coatings, but the obtained metallic and ceramic coatings show poor adhesion strength, and the underlying composite material is damaged by the APS process. This PhD is organized around two objectives:- Fundamental objective: understand the interactions between molten particles and the composite. A multi-scale study of droplets impacts on the composite led to identify the epoxy resin as responsible for the poor adhesion strength of air plasma sprayed coatings on CFRPs.- Experimental objective: determine the feasibility of producing an anti-wear coating by plasma spraying on CFRP. Two surface treatments prior to APS were chosen and tested in single particles impacts and coating formation. Alumina coatings have been obtained, without thermal or mechanical degradation of the underlying composite.

Residential roofs have traditionally formed the weakest part of the structure. The connections of roofs to the walls has lacked a clear load path with the result that the structure is weak at this point, leading to the compromise of the structure. Indeed roofs have multiple points of failure that lead to the weakness of the residential structure as a whole. Even if structural failure does not occur, compromise the roofing membrane can lead to high repair costs and property loss. The failure lies in the complex forming of the roof components as the roof aesthetics are placed to protect the underlayment and the underlayment protects the sheathing and trusses. However, the aesthetics, such as the roof tile, not being structural can be damaged easily and lead to the compromise of the roofing system as well as endangering surrounding structures. The shape of the roof tile lends itself well to structural design. The wave motion leads to structural redundancy and provides a significant ability to provide stiffness. Using the shape of the roof tile, a structure can be created to encapsulate the shape and provide structural strength. The aesthetics are already accounted for in the shape and the shape is strengthened according to necessity. A system has been devised for flexural strength and applicable connections to demonstrate the constructability and feasibility of creating and using such a system. Design concepts are accounted for, the components are tested and confirmed, and a full-scale test is carried out to demonstrate the concepts ability as a system. The outgrowth of this work is to produce design tables that allow the designer the ability to design for certain building conditions. Taking the concepts of flexural strength and wall to roof, panel to panel, and ridge connections, the design is broken down into appropriate design parameters. Tables are developed that allow the concept to be used under different structural conditions and geographical needs. The conclusion allows us to show specifically how the concept can be applied in specific geographical regions.

Previous studies have demonstrated that the behavior of fiber reinforced polymers (FRPs) bonded to metallic utility poles are governed by the following failure modes; yielding of the metallic substrate, FRP tensile rupture, FRP compressive buckling, and debonding of FRP from the substrate. Therefore, an in situ method can be devised for the repair of utility poles, light poles, and mast arms that returns the poles to their original service strength. This thesis investigates the effect of damage due to vehicular impact on metallic poles, and the effectiveness of externally-bonded FRP repair systems in restoring their capacity. Damage is simulated experimentally by rapid, localized load application to pole sections, creating dents ranging in depth from 5 to 45% of the outer diameter. Four FRP composite repair systems were selected for characterization and investigation due to their mechanical properties, ability to balance the system failure modes, and installation effectiveness. Bending tests are conducted on dented utility poles, both unrepaired and repaired. Nonlinear finite element models of dented and repaired pole bending behavior are developed in MSC.Marc. These models show good agreement with experimental results, and can be used to predict behavior of full-scale repair system. A relationship between dent depth and reduced pole capacity is developed, and FRP repair system recommendations are presented

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No / This paper presents a numerical method for estimating the curvature, deflection and moment capacity of hybrid FRP/steel reinforced concrete beams. A sectional analysis is first carried out to predict the moment-curvature relationship from which beam deflection and moment capacity are then calculated. Based on the amount of FRP bars, different failure modes were identified, namely tensile rupture of FRP bars and concrete crushing before or after yielding of steel reinforcement. Comparisons between theoretical and experimental results of tests conducted elsewhere show that the proposed numerical technique can accurately predict moment capacity, curvature and deflection of hybrid FRP/steel reinforced concrete beams. The numerical results also indicated that beam ductility and stiffness are improved when steel reinforcement is added to FRP reinforced concrete beams. (C) 2015 Elsevier Ltd. All rights reserved,

In this thesis the experimental results of seven full-scale glass fiber-reinforced polymer (GFRP) reinforced concrete (RC) slab-column edge connections are presented. The dimensions of the slabs were 2,800×1,550×200 mm with a square column measuring 300×300×2,200 mm. The test connections were divided into two series. Series I included three connections investigating the effect of flexural reinforcement ratio (0.90, 1.35 and 1.80%) when high strength concrete (HSC) is used, while Series II included four connections investigating the effect of GFRP shear reinforcement type and pattern on normal strength concrete (NSC) connections. Test results showed that increasing the reinforcement ratio increased the punching capacity and the post-cracking stiffness of the HSC connections. Furthermore, the use of headed studs and corrugated bars increased the punching capacity and the deformability of the NSC connections. Test results were compared to the predictions of the Canadian and American design provisions for FRP-RC structures. / February 2017

The shear failure mechanisms of flexural reinforced concrete (RC) members is highly complex; its precise details cannot be explained with simple analytical relationships, and are the topic of considerable scientific debate. The studies described and examined the three most used shear theories in the world – the fixed angle truss model (45°TM), the variable angle truss model (VAT), and modified compression field theory (MCFT). These three theories rest on the assumption that a beam loaded in shear behaves as a truss. However, this assumption is applied in different ways in various codes. In this thesis, three major standards, each of which uses a different implementation of these theories (CEN, 2005; ACI-318, 2008; CSA-A23.3, 2009), were used to predict the shear force capacity of a RC railway bridge that was strengthened in flexure with near surface mounted (NSM) carbon fibre reinforced polymers (CFRP) and then tested to failure. The data obtained in this test indicated that the codes underestimated the real shear behaviour of the bridge. There are some accepted reasons for such inaccuracies, namely the use of empirically derived equations in the ACI (2008) and CSA (2009) standards and the omission of the concrete contribution in CEN (2005). Moreover, the NSM reinforcement material used exhibits elastic behaviour until the point of failure; it was found that the use of such materials introduces further decreases the accuracy of the models’ predictions. The strains that developed in the area of the bridge where shear failure was expected were monitored throughout the test using a specially-developed photographic method. The results obtained with this method were promising, especially for research purposes, since it generated reliable data using relatively affordable tools.The use of FRP for shear strengthening introduces further complications to the problem of shear in reinforced concrete members because introduces two new failure modes: debonding at the concrete interface and fibre rupture of the FRP. Extensive research has been carried out on FRP shear strengthening around the world. Much of the data gathered in these studies has been compiled in a database. By analysing this large database, it was found that the effectiveness of FRP shear strengthening is influenced by many factors, including the properties of the FRPs, the FRP strengthening configuration used, the nature of the beam’s cross-section, the shear span to depth ratio, the presence of stirrups, and the nature of the tensile reinforcement. Analysis of this database also demonstrated that most of the studies reported in the literature had focused on investigating the influence of the properties of the FRPs and the different configuration systems, and that the other factors mentioned above have been sparsely investigated if not totally ignored. The strengthening configuration and the amount of fibres influence the failure mode of the FRP and the shear force that it can carry. It appears that the side-bonded and the U-wrapped configurations are most prone to failure by debonding. This is consistent with the findings of various small experimental programs, and was confirmed by analysis of the larger dataset. These findings are relevant because failure of the FRP by debonding is more complex mechanism than is the rupture of the fibres mechanism. As is shown in this thesis, the extent to which the FRP variables (properties and strengthening configuration) can affect the point at which failure occurs and the mode by which it happens is dependent on the quantity of stirrups and tensile reinforcement in the beam, to the position of the load in relation to the size of the cross section (shear span to depth ratio), the type of strengthening configuration, the concrete and FRP properties. For design purposes, it is important to predict the shear failure of FRP shear strengthened beams with as much accuracy as possible. Therefore, a design model for debonding of the shear strengthening of concrete beams with FRP was developed and the limitations of the truss model analogy were highlighted. The fracture mechanics approach was used to analyse the behaviour of the bond between the FRP composites and the concrete. In this model, of the parameters examined, the fracture energy of concrete and the axial rigidity of the FRP are considered to be the most important. The effective strain in the FRP when debonding occurs was determined and the limitations of the anchorage length over the cross section were analysed; ultimately, a simple iterative method for shear debonding was proposed. Since the model’s predictions were considered satisfactory but not really precise, an extensive review of the literature was conducted. All of the significant theoretical models for predicting the shear capacity of FRP strengthened RC beams that have been reported over the years were analysed and commented on, and their predictions were compared to the results recorded in a preliminary experimental database. The predictions of the models that are most widely used in design were compared to the experimental results reported in the database; the model developed by the author was evaluated alongside these more established models. All of the models, including that presented in this thesis, were found to generate inaccurate predictions, but two models have been calibrated so as to provide safe estimates of the FRP shear capacity. Finally a new model for FRP shear strengthening was proposed for use in engineering. The new model was developed on the basis of an analysis of the contents of the database of experimental findings. The model incorporates several design equations adopted from various models and is set up for engineering use. The predictions of the shear force carried by the FRP strengthening material are found to be conservative. / Godkänd; 2011; 20110328 (gabsas); DISPUTATION Ämnesområde: Konstruktionsteknik/Structural Engineering Opponent: Professor Giorgio Monti, University of Rome, Italy Ordförande: Professor Björn Täljsten, Institutionen för samhällsbyggnad och naturresurser, Luleå tekniska universitet Tid: Fredag den 29 april 2011, kl 13.00 Plats: F1031, Luleå tekniska universitet