Flexural strengthening of concrete beams using CFRP, GFRP and hybrid FRP sheets

Fiber-reinforced polymer (FRP) composites are extensively used in advanced concrete technology given their superiority over traditional steel reinforcements. These materials possess high strength capacity and corrosion resistance and can be employed as the main reinforcements in combination with adhesives and anchorages to strengthen reinforced concrete (RC) beam members. RC beams are designed to provide resistance against flexure , shear, torsion, fatigue, impact, and blast loading. The strength and ductility of RC beams can be improved via FRP strengthening techniques with a combination of fibers. The overall strength of FRP composites in RC beams is controlled by fiber type , configuration, and materials and strengthening technique. This review focuses on the characteristics and behaviors of FRP-strengthened RC beams under various loading conditions. It also presents the typical FRP composites with the properties, features, and applications. This review demonstrates that FRP composites can be used to recover the strength of damaged and corroded beams and exhibit good durability and insulation performance. It also provides a straightforward perspective of strengthening and retrofitting techniques for RC beams using FRP composites.

Strengthening of reinforced concrete beams by using fiber-reinforced polymer composites: A review

Properties and applications of FRP in strengthening RC structures: A review

Performances, challenges and opportunities in strengthening reinforced concrete structures by using FRPs – A state-of-the-art review

Fiber Reinforced Polymer (FRP) composite products such as Carbon FRP (CFRP) or Glass FRP (GFRP) have been intensively studied for strengthening reinforced concrete (RC) and masonry structures. It has been reported that FRP strengthening is effective to enhance the structural load-carrying capacity. Basalt FRP (BFRP) is a promising material for the application to structure strengthening with its advantages of low cost, corrosion resistant and sound mechanical property, but only limited studies of using Basalt FRP to externally strengthen RC beam are available in the literature. This study is to experimentally explore the effectiveness of application of Basalt FRP to strengthen RC beam under three-point bending test. The damage modes and structural response of unstrengthened and BFRP strengthened RC beams were recorded and identified. The effects of various BFRP wrapping schemes, U-jacket anchorage and epoxy adhesives on the flexural capacity of RC beams were analysed and discussed. In addition, the formulae used to predict the flexural behaviour of RC beam strengthened by other FRP composites (e.g. CFRP/GFRP) were evaluated for their applicability to Basalt FRP strengthening.

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Experimental study of flexural behaviour of RC beams strengthened by longitudinal and U-shaped basalt FRP sheet

Seismic performance of reinforced concrete beam–column joint strengthening by frp sheets

The recent earthquakes have shown that the vulnerability and the defects of the concrete joints in beam– column framed structures were the main causes for many building collapses. Such vulnerability and defects are in general the consequences of many factors. External strengthening with composite materials represents an alternative and a sound and efficient technique to improve the performances and aptitude to withstand seismic action. However, while the use of such strengthening technique offers many advantages, it has some disadvantages, particularly a remarkable loss of ductility. The present study examines the effects of an external strengthening of reinforced concrete beam–column joints against cyclic loading using CFRP laminates and GFRP sheet. The experimental program is constituted of three beam–column reinforced concrete joints at a scale of one to three (1/3) tested under the effect of a prestressing axial load acting over the column. The beams were subjected at their ends to a reverse cyclic lo...

Efficiency of Beam–Column Joint Strengthened by FRP Laminates

The use of composite materials for the strengthening and repair of structural elements is being increasingly used throughout the world. However, in addition to its higher cost, the greater strength of the FRP is inducing fragile behaviour at or close to failure. This fragile behaviour is not recommended for structures in seismic regions. In this sense, the aims of the present study, is to evaluate the contribution of the external reinforcement of concrete beams, reinforced by hybrid FRP laminates; which consist of the combination of one-way glass and carbon fibres as well as a bidirectional hybrid fabric glass carbon, on their performance in term of ductility, strength and mode of failure. An experimental program on a total of ten concrete beams reinforced by various hybrid configurations of reinforcement , tested up to failure under a cyclic loading in four points bending, to determine the best combination of the strengthening scheme.

Strengthening Reinforced Concrete Beams Using Hybrid FRP Laminates

Each operation to strengthen or repair requires special consideration and requires the use of methods, tools and techniques appropriate to the situation and specific problems of each of the constructs. The aim of this paper is to study the pathology of building of reinforced concrete towards the earthquake and the vulnerability assessment using a non-linear Pushover analysis and to develop curves for a medium capacity building in order to estimate the damaged condition of the building.

N. Attari

Papers

Flexural strengthening of concrete beams using CFRP, GFRP and hybrid FRP sheets

Seismic performance of reinforced concrete beam–column joint strengthening by frp sheets

Efficiency of Beam–Column Joint Strengthened by FRP Laminates

Strengthening Reinforced Concrete Beams Using Hybrid FRP Laminates

Pushover Analysis of a Seismic Strengthening of an Existing Building Reinforced Concrete Structure