The results of this active research have led to significant developments in seismic retrofitting and rehabilitation procedures. Research article materials and jacketing technique. Fiber reinforced polymers for seismic retrofitting of structures. Pdf seismic retrofitting by frp of a school building. Frp material are linear elastic under tension and do not yield, hence, the redistribution of the moments is not allowed and seismic energy cannot be. Frp materials as a retrofitting technique for the structures not designed to resist seismic action. In september 1999, the japan building disaster prevention association jbdpa published the seismic retrofitting design and construction guidelines for existing reinforced concrete rc and steelencased reinforced concrete src buildings with frp materials. While substandard structures are in need of retrofitting, particularly in seismic areas, problems such as high costs and disturbance to occupants are major obstacles.
Polymers free fulltext seismic behavior of substandard. Sikawrap seismic strengthening systems help ensure buildings, bridges, towers and other structures can withstand much higher earthquake loadings, and. Innovative applications of textilebased composites in. The authors have spent 3 years researching the technology and the available guidelines. The research in this report concentrates on retrofitting deficient rc columns by jacketing columns to improve their seismic performance and prevent the possible collapse of a structure. Pioneered since the 1980s by quakewrap president, professor mo ehsani. Frp composite wraps for seismic repair to assess the effectiveness of this repair technique, damaged column specimens from another experimental. Department of civil engineering and environmental engineering, stanford university, california, usa. For seismic retrofitting, it is essential that the frp material is tight against the structure.
The traditional method of repairing or strengthening reinforced concrete columns by means of concrete or steel jacketing involves difficult implementation procedures especially in building columns. Many existing reinforced concrete structures were constructed with substandard characteristics. Advancements in retrofitting reinforced concrete structures. Seismic retrofitting definition, techniques using modern. A relatively new paradigm, performancebased design, has also had an impact on seismic retrofitting and rehabilitation. This study aims to develop retrofitting scheme for restoring the structural performance of corroded confined concrete hinge regions of rc columns. Seismic retrofit, strengthening and repair by quakewrap. Two primary methods are used to attach frp composite materials to concrete structures and to masonry, timber, and even metallic structures for retrofitting purposes.
One method employs permanufactured rigid frp strips approximately 4 in. Textile reinforced mortars trm versus fiber reinforced. Aug, 2001 some key behaviour and design aspects for shear. Increasing the strength of existing building using frp. Seismic retrofit of framed buildings, fibrereinforcedpolymer structure, baseisolated structure, addeddamping structure, nonlinear dynamic analysis. The retrofit techniques are also applicable for other natural hazards such as tropical cyclones, tornadoes, and severe winds from thunderstorms. Life cycle assessment of sustainable infrastructure materials.
Also, changes in service conditions, often made arbitrarily, may lead to substantial changes in the structural behaviour resulting in a degradation of the. Seismic retrofit or rehabilitation strategies have been developed in the past few decades following the introduction of new seismic provisions and the availability of advanced materials e. The research developed in this paper concerns seismic frp reinforcement. Increasing the strength of existing building using frp materials in seismic zone vijay singh rawat department of civil engineering pacific university udaipur rajasthan. Research article materials and jacketing technique for. Seismic retrofitting techniques for concrete structures focuses procedures to improve evaluation of seismic vulnerability of reinforced concrete buildings and provide innovative retrofitting techniques such as base isolation and mass reduction. Frp materials as a means of strengthening civil engineering structures. Low quality concrete, poor transverse reinforcement details and insufficient flexural strength are among the most common deficiencies. The memberlevel retrofit approaches include the addition of concrete, steel, or fiber reinforced polymer frp jackets for use in confining rc columns and joints. Philosophy for strengthening seismic upgrade of structures located in seismic areas is generally aimed either at improving their seismic. Pioneered since the 1980s by quakewrap president, professor mo ehsani, frp is applied similar to wallpaper and becomes 23 times stronger than steel in 24 hours. Fiber reinforced polymers for structural retrofitting.
Retrofit of rectangular bridge columns using cfrp wrapping. Frp composite wraps for seismic repair to assess the effectiveness of this repair technique, damaged column specimens from. Seismic analysis of a rc frame building with frp retrofitted. Apr 26, 2012 the jbdpa guidelines mainly focus on seismic retrofitting of structural elements, which implies the strengthening for shear of deficient structural elements.
Consequently, new retrofitting methods for columns. Frp have attracted the attention of researchers and bridge owners as an alternative material for retrofitting reinforced concrete bridge elements. Repair of earthquakedamaged rc columns with frp wraps. Many strengthening techniques have been introduced aimed at improving the structural performance of existing structures that, if properly designed and applied, provide an effective contribution. Sikawrap fibre reinforced polymer structural strengthening. Seismic retrofitting by frp of a school building damaged by emiliaromagna earthquake article pdf available in key engineering materials 624. Research article materials and jacketing technique for retrofitting of structures shri. Educational and research university, chennai, tamil nadu, india. A brief explanation of this retrofitting method as given in the recently published version of turkish seismic design code is also included as well. However, as of this day, there is no national guideline available which sets down recommendations for the design and detailing of frp for strengthening of civil engineering structures. Seismic retrofitting of corroded rc columns using advanced.
A common frp strengthening methods used for shear enhancement or inadequate length lap splice enhancement are passive methods. To achieve widerange use of these materials, however, there is need for further research into a number of issues related to mechanics, design, and durability of frp retrofitted concrete and steel systems. Frp in form of fibre, when continuously and rigidly connected to the beams and columns of the frame, are able to carry out to absorb the horizontal forces, increasing the capacity to absorb seismic forces. Retrofitting of concrete, cfrp, gfrp, bfrp, seismic retrofitting, retrofitting of beam, column. Now apply the epoxy mixture on concrete cylinder with the help of brush to paste the glass fiber reinforced polymer gfrp.
In this paper we dealt with how the different frp materials could be used as a retrofitting material and be used based on cost effective 16. Appendix 11 section 11 japanese design and construction. This paper describes and comments on some of the design approaches provided by the jbdpa guidelines for the strengthening of reinforced concrete rc columns. Pdf retrofitting is a process that is used to improve the strength, durability and performance of the structure. It summarizes the scopes and uses of frp materials in seismic strengthening of rc structures and masonry retrofitting as well as the seismic retrofitting schemes for steel structures. A reliable numerical evaluation of the nonlinear behaviour of historical masonry structures, before and after a seismic retrofitting, is a fundamental issue in the design of the structural retrofitting. Such problems can be reduced through proper design and anchorage of the external frp reinforcement. Retrofitting highrise structures using frp composite materials by david white f iberreinforced polymer frp composite materials have become a viable and accepted means of upgrading, strengthening, and rehabilitating structures over the past three decades. Seismic retrofitting is a process to modify or upgrade existing structures to make them resistant to earthquakes. Whereas materials like fiber reinforced polymer frp, basalt fiber. Retrofitting using frp laminates make a mixture of epoxy resin and hardener in the ratio of 100. Retrofitting with frp materials is a technically sound and cost effective repair technology and is now extensively being used as a seismic retrofitting method all over the world.
The first seismic application of frp materials, thanks to their high strength, exhibited an effective performance for monotonic and seismic. Buildings free fulltext nonlinear modelling of curved. Jun 11, 20 sikawrap seismic strengthening systems help ensure buildings, bridges, towers and other structures can withstand much higher earthquake loadings, and meet new zealands new earthquake regulations too. Finally, key issues on the seismic retrofitting of masonry walls for in. This study employs advanced composite materials such as highperformance fibre reinforced concrete hpfrc and glass fibre reinforced polymer gfrp in.
The concrete must start to crack up and dilate before the composite can take over. The jbdpa guidelines mainly focus on seismic retrofitting of structural elements, which implies the strengthening for shear of deficient structural elements. This report presents the findings of an experimental study conducted on rectangular bridge columns retrofitted using frp. Retrofitting techniques for existing damaged buildings.
Seismic retrofitting of concrete members with frp composites free download as powerpoint presentation. In the research reported in this paper, the feasibility of using glass fiber composite laminates gfcl locally available in the egyptian market in retrofitting flexural reinforced concrete elements is studied. Frp composites are widely recognized for their potential use in seismic retrofitting applications. Thus, decision makers must approach using these materials with caution and must ensure that the design is performed with adequate knowledge and. Kobatake, technical research institute, obayashi corporation, japan abstract new retrofitting techniques using carbon fibers are presented.
Since the 1990s, composite materials applied by the wet layup method have become the main seismic reinforcement technology for civil engineering structures. Outline of the japanese guidelines for seismic retrofitting of rc buildings using frp materials open pdf. Seismic retrofitting techniques for concrete structures. The focus of this paper is mainly on the retrofitting of bridge superstructures and substructures including decks, girders, frames, and columns.
Seismic retrofit with frp materials has gained notable acceptance from the civil engineering community in recent years. For existing reinforced concrete columns, a cfrp winding technique is. Innovative materials for seismic and energy retrofitting of. Once the decision is made, seismic retrofitting can be performed through several methods with various objectives such as increasing the load, deformation. Effect of external frp retrofitting on reinforced concrete. Fiber reinforced polymers frp are investigated in this study in comparison with a new class of materials, textile reinforced mortars trm, for shear strengthening andor seismic retrofitting of concrete structures. Despite the low probability of occurrence, risks related to natural disasters are considered to be unacceptable. Retrofitting of concrete structure with fiber reinforced polymer.
We are a team of structural engineers and construction professionals focused on providing customized solutions for repair, retrofit and strengthening of structures using carbon fiber reinforced polymer frp products. The most of the structure throughout the world have seismic effect and are not capable of withstanding earthquake action according to the current code. Polymers frp as strengthening materials of concrete structures by t. Pdf fiber reinforced polymers for structural retrofitting. Innovative textilebased composites for strengthening and. Seismic retrofitting of concrete members with frp composites. Seismic retrofitting definition it is the modification of existing structures to make them more resistant to seismic activity, ground motion, or soil failure due to earthquakes. Column jacketing column retrofitting is often critical to the. Overview of the japanese guidelines for seismic retrofitting. They provide many advantages over conventional mate. Waghmare address for correspondence acharya shrimannarayan polytechnic,piprim, wardha maharashtra abstract seismic protection of buildings is a needbased concept aimed to improve the performance of any structure under future earthquakes.
Epoxy epoxy is one of the most versatile materials used in structural repair and retrofitting and it is used as a sealant, adhesive or mortar. This report presents the findings of an experimental study conducted on rectangular bridge columns retrofitted using frp composite materials. Wrapping the gfrp sheet or laminate tightly over a concrete cylinder in a two layers and apply the epoxy coat. The course drew on expertise both from outside turkey and from the large pool of local experts on this subject. Outline of the japanese guidelines for seismic retrofitting.
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