The lack of design guidance is thus a major impediment to the widespread implementation of frp anchors in the strengthening of rc structures. In 1948, an rc bridge deck in sweden needed to be upgraded in its negative moment region. Frp reinforcements are bonded to concrete surfaces by adhesives but frequently experience debonding failure at the interface between frp. An important difference in bond behavior between frp strengthened concrete structures and frp strengthened steel structures is the exact location of interfacial failure. Reliabilitybased design of frp flexural strengthened. An overview of sprayed frp retrofitting and strengthening of rc structures heangki lee1, sungkug ha2 summary the present paper summarizes an overview paper lee and ha, 2007 recapitulating representative papers regarding the previous and ongoing researches on sprayed frp retrofitting and strengthening of rc structures. Disbond detection with piezoelectric wafer active sensors. Finite element modeling of rc connections strengthened with frp laminates. Description of the book frpstrengthened rc structures. The strengthening of reinforced concrete rc structures using advanced fibrereinforced polymer frp composites, and in particular the behaviour of frpstrengthened rc structures is a topic which has become very popular in recent years. Experimental analysis of rc elements strengthened with.
An eb frp plate frequently shows debonding which is very brittle, while nsm strip strengthening can slips widely and provide higher rotational capacity 157, 159. Overview of main design guidelines for frp strengthened rc beams. Repair and strengthening of reinforced concrete structures. Near surface mounted nsm frp rods are now emerging as a promising technique, in addition to externally bonded frp laminates, for increasing flexural and shear strength of rc members. Article information, pdf download for experimental study on intermediate crack debonding in. It has recently been my experience to adopt such a strengthening method, using cfrp plates, to strengthen a structure so that it could accept seismic loads. According to the design equation utilized for lrfd, the design standards and guidelines for frp strengthened rc structures can be divided into two categories. Strengthening of reinforced concrete structures with near. Two design examples, based on those originally contained in aci 440. Modeling the fire performance of frpstrengthened reinforced. Some other powerups which may allow to swap letters etc.
In order to address such knowledge gap, a rational design methodology for frp anchors in frp strengthened rc structures is proposed herein. The strengthening of reinforced concrete rc structures using advanced fibre reinforced polymer frp composites, and in particular the behaviour of. The fiber reinforced polymer frp strengthening concepts have been in many studies usedto strengthen these rc structures in resisting progressive collapse, structural damage and. Durability considerations for frpstrengthened rc structures. Request pdf frpstrengthened rc structures the strengthening of reinforced concrete rc structures using advanced fibrereinforced polymer frp. The strengthening of reinforced concrete rc structures using advanced fibrereinforced polymer frp composites, and in particular the behaviour of frp strengthened rc structures is a topic which has become very popular in recent years. Thus, the focus of this paper is to present the development of a numerical model for predicting the performance of frp strengthened beams. Reliability assessment for flexural frpstrengthened. When an rc structure is strengthened with externally bonded frp, the bond between frp and concrete plays a crucial role in guaranteeing the effectiveness of the strengthening. Strengthening design of reinforced concrete with frp. Downloaddownload free pdf frp strengthened rc structures. Behaviour and strength of frpstrengthened rc structures.
Preface notation frp composites for strengthening rc structures bond strength of frptoconcrete joints flexural strengthening of beams shear. At present, there is very limited information in the area of fire resistance modeling to frp strengthened structures. This popularity has arisen due to the need to maintain and upgrade essential infrastructure in all parts of the world, combined with the. An overview of sprayed frp retrofitting and strengthening of. Repair of precracked reinforced concrete rc beams with. A design approach for frp anchor s in frpstrengthened rc structures enrique del rey castillo, jaso n m. The th international symposium on fiberreinforced polymer reinforcement for. This popularity has arisen due to the need to maintain and upgrade essential infrastructure in all parts of. An overview of sprayed frp retrofitting and strengthening. Strengthening of rc members using nearsurface mounted. Crack width and loadcarrying capacity of rc elements. Teng the hong kong polytechnic university, china j. Strengthening of steel structures with fiberreinforced. Frp reinforcement in rc structures pdf fib bulletins n 40.
In frp strengthened rc structures, one of the main failure modes is the separation of frp from concrete debonding 1. The tests in the database were conducted over a long time span from 1993 to 2018. This popularity has arisen due to the need to maintain and upgrade essential infrastructure in all parts of the world, combined with the wellknown. Flexural strengthening of slab typical frp strengthening applications flexural strengthening of beam shear strengthening and confinement of column wrapping of concrete tank shear strengthening of beamcolumn joint helza et al. The flexural behavior of pfrp strengthened rc beams was investigated. Very recent works about strengthening steel structures using frp are those of schnerch and rizkalla 30 and rizkalla et al. Flexural performance of rc beams strengthened with polyester. The strengthening of reinforced concrete rc structures using advanced fibre reinforced polymer frp composites, and in particular the behaviour of frpstrengthened rc structures is a topic which has become very popular in recent years. A design approach for frp anchors in frp strengthened rc structures. Nondestructive evaluation of rc structures strengthened.
Frpstrengthened rc structures request pdf researchgate. The need for strengthening a reinforced concrete beam or a number of beams in a structure is usually caused by problems due to degradation of characteristics of materials with time, reduction in cross section, corrosion, wrong initial design or the increase in the load demand on the building when its utilized for a new purpose other than. Fire endurance of insulated frpstrengthened square concrete. This popularity has arisen due to the need to maintain and upgrade essential infrastructure.
Among the various strengthening techniques that have been developed and applied to strengthen deteriorated rc structures, a number of applications using frp reinforcements have significantly increased recently. Using frp motivates civil engineers to strengthen existing rc structures and repair any deterioration. Strengthening of reinforced concrete structures different strengthening techniques. The dimension of these concrete beams used was 150 mm. Experimental investigation on flexural behavior of rc. Application of sprayed frp coating to fullscale rc structures conducted by researchers is then. Analytical design approach 4 mohammadali rezazadeh 21, joaquim a. Frpstrengthened rc structures provides readers with a comprehensive guide to the fundamental theory that underpins the use of bonded fibrereinforced polymers frp to strengthen structures. The background of the main physical and mechanical properties of frp. This work is the result of experimental research conducted to determine the contribution of a composite material to improving the mechanical behavior of old, fullsize reinforced tbeams in operation conditions under the action of shortterm loads. Highperformance laminates of fiber reinforced polymer frp, especially the carbon fiber reinforced polymer cfrp sheets, are widely used in the strengthening of reinforced concrete rc structures due to high strength toweight ratio, excellent corrosion resistance and easy installation. Fire endurance of insulated frp strengthened square concrete columns by v.
A design approach for frp anchors in frpstrengthened rc structures october 2017 conference. Otoom centre for built infrastructure research, faculty of engineering, university of technology, sydney, australia 1. Design approach for frp spike anchors in frpstrengthened rc. The overall objective of this research project was to investigate the effectiveness of nsm frp rods as a strengthening system for rc structures. Description of the book frp strengthened rc structures. Design approach for frp spike anchors in frpstrengthened. Necessity of strengthening of steel structures with frp. Guidelines with a resistance factor design format, i. In this study, costeffective polyester fiber reinforced polymer pfrp composite plates were used as external strengthening materials of conventional reinforced concrete rc beams.
It consolidates the information presented in research papers into one allencompassing reference on the subject. Generally, a strong frp concrete bond leads to brittle failure of the whole rc structure, whereas a weak bond may cause debonding and ductile failure of frp strengthened structures. Teng and others published design guidelines for fibre reinforced polymer frpstrengthened reinforced concrete rc structures find, read and cite all the. History of the technology the use of nsm reinforcement was developed in europe for strengthening of rc structures in the early 1950s. Free download ebooks 20080707 12 42 03 ad c documents and settings all users application data temp i think the 830 is an interesting device at its price. Because of the high strength of frp materials, most failures of frp strengthened rc members are caused by debonding along frp toconcrete interfaces. Barros, honeyeh ramezansefat 3, 5 6 abstract 7 fiber reinforced polymer frp composite materials applied according to the nearsurfacemounted nsm technique 8 are very effective for the flexural strengthening of reinforced. Frp strengthening of steel and steelconcrete composite.
Frp reinforcement in rc structures technical report. Download product flyer is to download pdf in new tab. A design approach for frp anchors in frpstrengthened rc. Increased use of fiber reinforced polymer frp materials for strengthening of concrete structures has raised concerns regarding the behavior of such frp systems in fire. Pdf a design approach for frp anchors in frpstrengthened. The strengthening of reinforced concrete rc structures using advanced fibrereinforced polymer frp composites, and in particular the behaviour of. Free download ebooks 20080707 12 42 03 ad c documents and settings all users application data temp i think the 830 is an interesting device at its price point. Frp reinforcement in rc structures fib bulletins n 40. Extensive research has been carried out in recent years on the use of fibrereinforced polymer frp composites in the strengthening of reinforced concrete rc structures. Two rc control beams and six pfrp strengthened rc beams were constructed and tested under fourpoint.
Durability considerations for frp strengthened rc structures in the australian environment s. Experimental study on intermediate crack debonding in frp. The beams are grouped into tw labeled s1 and s2 and each series have different percentage of steel reinforcement. Current design guide lines propose a method to predict the flexural behaviour of frp strengthened elements based on classic equilibrium and strain compatibility, usually within the elastic range of the materials. First, bond characterization of nsm rods was carried out on couponsize specimens, varying type of frp rebars, bonded length and groove size. Flexural performance of rc beams strengthened with. The th international symposium on fiber reinforced polymer reinforcement for concrete structure. Extensive research has been carried out in recent years on the use of fibrereinforced polymer frp composites in the strengthening of. Smith and lui lam, year2001 preface notation frp composites for strengthening rc structures bond strength of frp toconcrete joints flexural strengthening of beams shear. Reinforced concrete rc structures might subject to severe impulsive loadings due to shock wave, blast wave or direct impact in their service life. Pdf behaviour and strength of frpstrengthened rc structures. Proceedings of the th conference on fiber reinforced polymers in reinforced concrete structures frprcs, american concrete institute aci, anaheim, ca, usa, 2017. The tension side of their ribs were strengthened by carbon strips of different lengths. A design approach for frp anchors in frpstrengthened rc structures.
Extensive research has been carried out in recent years on the use of fibre reinforced polymer frp composites in the strengthening of. Strengthening structures via external bonding of advanced fibre reinforced polymer frp. In this regard, the evolving technology of using carbonbonded fibrereinforced polymers cfrp for strengthening of rc beams. Dec, 2012 the strengthening of reinforced concrete rc structures using advanced fibre reinforced polymer frp composites, and in particular the behaviour of frpstrengthened rc structures is a topic which has become very popular in recent years. This has led to extensive research, both experimentally and numerically, on. Nondestructive evaluation of rc structures strengthened with. The strengthening of reinforced concrete rc structures using advanced fibre reinforced polymer frp composites, and in particular the behaviour of frpstrengthened rc structures is a topic. Iranian journal of science and technology transaction bengineering 30 1 experimental investigation into bond behavior of cfrp sheets attached.
Some strengthening methods using highperformance protection layers 3 or coating layers 4 have been proposed in the practical repair and strengthening of structures, however, there are many frp repair materials used in strengthened. Strengthening rc beams using externally bonded cfrp sheets. In recent years, frp has been increasingly used as a substitute for traditional steel reinforcements in rc structures due to its superior material properties, such as. Frp strengthened rc structures civil engineering community. Pdf properties and applications of frp in strengthening. First, the disbond detection method were developed on coupon specimens consisting of concrete blocks covered with an frp composite layer.
In frpstrengthened rc structures, one of the main failure modes is the separation of frp from concrete debonding 1. Pdf synopsis extensive research has been carried out in recent years on the use of fibrereinforced polymer frp composites in the strengthening of. Fiber reinforced polymer frp composites are being utilized in a wide range of application areas in structural rehabilitations because these materials are less affected. Similar with reference, in this paper, a comprehensive test database of flexural frp strengthened rc beams is constructed. In order to address such knowledge gap, a rational design methodology for frp anchors in frpstrengthened rc structures is proposed herein. Disbond detection with piezoelectric wafer active sensors in. Similar to reinforced concrete rc structures strengthened with externally bonded frp reinforcement, interfacial debonding failures also control the loadcarrying capacity of steel structures strengthened with externally bonded frp reinforcement in many cases. International journal of adhesion and adhesives 48, 150158. In design process we must take two important points in considerations. In order to investigate the performance degradation of rc structures strengthened by various main frp materials under ultraviolet light, a series of simulated accelerated test investigations have. Anchorage systems for reinforced concrete structures. Two rc control beams and six pfrp strengthened rc beams were constructed and tested under fourpoint bending. A series of experiments conducted to characterize tensile strength, shear bond behavior and anchorbond capacities of the sprayed frp coating are summarized. Introduction to repair and strengthening of reinforced concrete structures 1.
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