Seismic retrofitting involves modifying existing structures to increase their resistance to seismic activity like earthquakes. It is important for historically significant buildings, areas prone to earthquakes, and tall or expensive structures. Retrofitting techniques can strengthen structures by increasing lateral strength, ductility, and strength-ductility. Some common retrofitting methods include adding new shear walls, steel bracing, base isolation, and column jacketing. Column jacketing involves wrapping columns with steel, reinforced concrete, or fiber-reinforced polymers to improve shear and flexural capacity. The selection of a retrofitting technique depends on factors like the structure type, material condition, cost, and effectiveness for the situation.
CE 72.52 - Lecture 8a - Retrofitting of RC MembersFawad Najam
The document outlines a presentation on retrofitting concrete structures. It discusses two approaches to retrofitting: global (system) strengthening which adds new elements to enhance stiffness, and local (element) strengthening which targets insufficient member capacities. Examples of global retrofitting mentioned include adding reinforced concrete shear walls and buckling restrained braces. Local retrofitting examples discussed are reinforcement concrete jacketing of columns and beams.
MBrace is a composite strengthening system that uses carbon fiber sheets bonded to concrete structures with epoxy resin to improve their strength and durability. It has advantages over traditional strengthening techniques like steel plating in that it is lighter, easier to install, and does not change the structure's original alignment. The multi-step MBrace installation process involves surface preparation, application of epoxy primer and saturant, attaching pre-saturated carbon fiber sheets, and optional protective topcoating. MBrace increases structures' load-bearing capacity, ductility, blast resistance, and can be used to retrofit beams, columns, walls, and other elements.
This document discusses retrofitting of structures. Retrofitting is required when structures are damaged or do not meet current seismic standards. It summarizes various retrofitting techniques such as adding shear walls, infill walls, steel bracing, wall thickening, wing walls, mass reduction, base isolation, and jacketing structural elements. It provides examples of existing retrofitted structures in Gujarat. Retrofitting increases strength and ductility but can reduce space and increase foundation loads. Materials discussed include steel, fiber reinforced polymer, and reinforced concrete.
Repair & Rehabilitation of Concrete Structures Using FRP CompositesParvez Ahmad Hashmat
Fiber-reinforced polymers are furthermore referred to as materials known as composites.
They are produced by a mixture of two or more basic or parent materials to make and form an enriched compound having upgraded properties.
Generally, FRP materials contain high strength fibers as (carbon, glass, or aramid )with an enriched polymer resin(vinyl ester, epoxy or polyester thermosetting plastic..), whereas the enriched fibers act, as the key reinforcing element, where the polymer resin or polymer matrix works as a holding or binder which transfers loads between fibers and protects fibers.
The document summarizes a study on retrofitting beam-column joints with carbon fiber reinforced polymer (CFRP) composites under cyclic loading. It discusses how beam-column joints are vulnerable during earthquakes and describes traditional and CFRP retrofitting techniques. It outlines the objectives, methodology, modeling and analysis of retrofitted and non-retrofitted beam-column joints in ANSYS. The results show that the CFRP retrofitted joint had 27.7% less deflection and carried more load than the non-retrofitted joint. The conclusion is that CFRP improves joint confinement and capacity.
Retrofitting is the seismic strengthening of existing damaged or undamaged structures.
Retrofitting a building involves changing its systems or structure after its initial construction and occupation. This work can improve amenities for the building's occupants and improve the performance of the building
Seismic retrofitting involves modifying existing structures to increase their resistance to seismic activity like earthquakes. It is important for historically significant buildings, areas prone to earthquakes, and tall or expensive structures. Retrofitting techniques can strengthen structures by increasing lateral strength, ductility, and strength-ductility. Some common retrofitting methods include adding new shear walls, steel bracing, base isolation, and column jacketing. Column jacketing involves wrapping columns with steel, reinforced concrete, or fiber-reinforced polymers to improve shear and flexural capacity. The selection of a retrofitting technique depends on factors like the structure type, material condition, cost, and effectiveness for the situation.
CE 72.52 - Lecture 8a - Retrofitting of RC MembersFawad Najam
The document outlines a presentation on retrofitting concrete structures. It discusses two approaches to retrofitting: global (system) strengthening which adds new elements to enhance stiffness, and local (element) strengthening which targets insufficient member capacities. Examples of global retrofitting mentioned include adding reinforced concrete shear walls and buckling restrained braces. Local retrofitting examples discussed are reinforcement concrete jacketing of columns and beams.
MBrace is a composite strengthening system that uses carbon fiber sheets bonded to concrete structures with epoxy resin to improve their strength and durability. It has advantages over traditional strengthening techniques like steel plating in that it is lighter, easier to install, and does not change the structure's original alignment. The multi-step MBrace installation process involves surface preparation, application of epoxy primer and saturant, attaching pre-saturated carbon fiber sheets, and optional protective topcoating. MBrace increases structures' load-bearing capacity, ductility, blast resistance, and can be used to retrofit beams, columns, walls, and other elements.
This document discusses retrofitting of structures. Retrofitting is required when structures are damaged or do not meet current seismic standards. It summarizes various retrofitting techniques such as adding shear walls, infill walls, steel bracing, wall thickening, wing walls, mass reduction, base isolation, and jacketing structural elements. It provides examples of existing retrofitted structures in Gujarat. Retrofitting increases strength and ductility but can reduce space and increase foundation loads. Materials discussed include steel, fiber reinforced polymer, and reinforced concrete.
Repair & Rehabilitation of Concrete Structures Using FRP CompositesParvez Ahmad Hashmat
Fiber-reinforced polymers are furthermore referred to as materials known as composites.
They are produced by a mixture of two or more basic or parent materials to make and form an enriched compound having upgraded properties.
Generally, FRP materials contain high strength fibers as (carbon, glass, or aramid )with an enriched polymer resin(vinyl ester, epoxy or polyester thermosetting plastic..), whereas the enriched fibers act, as the key reinforcing element, where the polymer resin or polymer matrix works as a holding or binder which transfers loads between fibers and protects fibers.
The document summarizes a study on retrofitting beam-column joints with carbon fiber reinforced polymer (CFRP) composites under cyclic loading. It discusses how beam-column joints are vulnerable during earthquakes and describes traditional and CFRP retrofitting techniques. It outlines the objectives, methodology, modeling and analysis of retrofitted and non-retrofitted beam-column joints in ANSYS. The results show that the CFRP retrofitted joint had 27.7% less deflection and carried more load than the non-retrofitted joint. The conclusion is that CFRP improves joint confinement and capacity.
Retrofitting is the seismic strengthening of existing damaged or undamaged structures.
Retrofitting a building involves changing its systems or structure after its initial construction and occupation. This work can improve amenities for the building's occupants and improve the performance of the building
This document discusses various techniques for retrofitting existing structures to improve their resistance to seismic activity. It describes adding new shear walls, steel bracing, or jacketing columns as common retrofitting methods. Base isolation, which isolates the structure from foundations, is also discussed. The objectives of retrofitting are outlined as increasing strength, ductility, and protecting life safety. Different classification of retrofitting techniques are provided based on addressing local deficiencies or global irregularities.
Effect of infill walls on the seismic performance of the multistoried buildingseSAT Journals
Abstract The most commonly used structural system in our country for almost all types of building are multi-storey reinforced concrete frames with masonry infills. Therefore it is essential to understand the seismic behaviour of these structures when subjected to lateral forces. Several research works has been done on the masonry infilled reinforced concrete frames in the past decades. Mortar is used as a binder in normal brick construction in order to create continuous structural form and to bind together the individual units in brickwork. In the present study, analysis has been carried out by considering the increase in height of building from five to ten storied by using finite element software ANSYS 14.5. The seismic analysis of multi-storeyed building frames with infill walls and without infill walls are conducted. 3D analysis will give more realistic values of deflection and stresses. Since this type of study is not feasible in terms of analysis time taken, 2D model was adopted for the present study. A three bay two dimensional building frame is considered with the number of stories varying from 5 storied to 10 storied. The loading applied is as per IS 1893 (Part I): 2002. Equivalent diagonal strut method is adopted for modelling infill walls. The results showed that there is considerable decrease in deflection when infills are used in RC frames. Key Words: Deflection , Equivalent diagonal strut method, lateral load, Solid brick infills, Storey drift
Seismic retrofitting is the modification of existing structures to make them more resistant to seismic activity, ground motion, or soil failure due to earthquakes.
CE 72.52 - Lecture 8b - Retrofitting of RC MembersFawad Najam
This document contains a presentation by Dr. Pramin Norachan on fiber reinforced polymer (FRP) systems for strengthening concrete structures. The presentation covers flexural, shear, axial and confinement strengthening using FRP. It discusses various FRP materials, design considerations, and design equations. The key points covered include the materials and properties of FRP, how FRP is used to enhance load capacity, ductility and durability of structures, and design approaches for flexural, shear and confinement strengthening.
This Presentation covers the technique of retrofitting of existing as well as worn out structures using FRP laminates. Thermal stresses are imposed into the samples to mimic fire in a building. It is then tested for strength, repaired using 250 gsm glass fiber reinforced polymer and then tested for strength again. It was observed that the lost strength of the samples subjected to thermal stresses was regained.
Strengthening structures via external bonding of advanced fibre reinforced polymer (FRP) composite is becoming very
popular worldwide during the past decade because it provides a more economical and technically superior alternative
to the traditional techniques in many situations as it offers high strength, low weight, corrosion resistance, high fatigue
resistance, easy and rapid installation and minimal change in structural geometry. Although many in-situ RC beams
are continuous in construction, there has been very limited research work in the area of FRP strengthening of continuous
beams.
Strengthening Of Beams for flexure Using FRPReham fawzy
This document discusses fiber reinforced polymer (FRP) composites used for strengthening concrete structures. It covers various topics such as FRP materials and systems, causes of structural defects, strengthening techniques, and design considerations. Specifically, it describes the different types of fibers and matrices used in FRP, advantages of FRP over traditional materials, and applications of FRP like flexural, shear, and axial strengthening of beams, columns, slabs and walls. It also identifies potential structural defects in design, construction or over the service life of a structure that could require strengthening.
Repair and Retrofit on Beam and Column Jointsamerald24
A research experiment has been conducted on the structural performance of repaired minor damaged reinforced concrete beam and column Joints using composite known as CFRP (Carbon Fiber Reinforced Polymer) under simulated cyclic 2D loadings to find the practical lamination repair scheme for flexural strengthening, shear strengthening, and joint strengthening.
This document summarizes research on strengthening reinforced concrete beams using fiber reinforced polymer (FRP) sheets. It discusses how FRP strengthening has become a popular technique worldwide due to advantages like high strength, light weight, corrosion resistance, and easy installation. The document reviews literature on strengthening both simply supported and continuous beams. It outlines different FRP strengthening methods and discusses factors that influence the behavior and failure of strengthened beams, such as surface preparation, adhesive type, and concrete strength. The document also discusses design considerations and challenges for FRP strengthening, as well as disadvantages like lack of design codes and fire risk.
This document discusses retrofitting techniques to strengthen existing structures against seismic activity. It describes upgrading reinforced concrete and masonry structures through methods like reinforced concrete jacketing, steel plate bonding, and adding new structural elements. Recent trends in Pakistan involve using carbon fiber reinforced polymer composites for flexural and shear strengthening. The document provides examples of retrofitting projects completed in Pakistan using these composite systems.
The document discusses retrofitting of reinforced concrete beam-column joints through various techniques like jacketing, case studies, and concludes with key findings. Specifically, it summarizes three case studies: 1) Retrofitting using reinforced concrete jacketing improved strength and ductility over the brittle original joint. 2) Using carbon fiber reinforced polymer on a damaged joint improved shear strength and ductility. 3) Glass fiber reinforced polymer wrapping a joint improved its shear and bond-slip resistance, producing more ductile failures in beams.
This document is a project report on the design of a shear wall using STAAD Pro software. It includes an introduction to shear walls, which are vertical structural elements that resist lateral loads like wind and earthquakes. The report discusses the purpose, applications, advantages, and disadvantages of shear walls. It also describes the different types of shear walls and their behavior under loads. The design procedure for shear walls in STAAD Pro and as per reference codes is explained. The conclusion summarizes that shear walls provide strength and stiffness to resist lateral loads in buildings.
This document discusses materials used for repairing and rehabilitating reinforced concrete structures. It covers various repair strategies like load reduction, crack repair, and strengthening of structural elements. It also discusses different types of materials used for surface preparation, corrosion protection, bonding, structural repairs, and other purposes. Key materials mentioned include cement mortars, polymer-modified cement products, epoxies, acrylics, and chemicals. The document provides guidelines on selecting appropriate materials based on properties like shrinkage, bond strength, thermal expansion, and durability. It also outlines various applications of polymer mortars and epoxies in structural repair and rehabilitation work.
This document discusses smart concrete invented by Professor Deborah Chung. Smart concrete is concrete that can sense its own strain or stress without embedded sensors. It has been modified with admixtures so that changes in electrical resistance allow it to function as a sensor. Two types were studied: one with short carbon fibers and one with carbon nanotubes. Laboratory experiments showed that when molded into squares with electrodes, both types demonstrated piezoresistive properties and were able to detect internal stress and strain, showing potential as sensors for pavement monitoring.
retrofitting of fire damaged rcc slabs,colums,beamsNayana 54321
This document discusses techniques for retrofitting existing reinforced concrete structures. It introduces various problems that can occur in concrete structures like damage, excessive loading, cracks, and corrosion. Retrofitting aims to restore strength and improve serviceability. Factors influencing the selection of a retrofitting technique include cost, time constraints, and existing structure conditions. Conventional techniques discussed are section enlargement, external plate bonding, external post-tensioning, ferrocement covering, and grouting. An advanced technique of fiber reinforced polymer composites is also introduced, with carbon fiber reinforced polymer being highlighted. CFRP has advantages of high strength, corrosion resistance, and suitability for seismic retrofitting but also has high initial costs.
This document discusses various techniques for retrofitting concrete structures to make them more resistant to seismic activity and other natural hazards. It defines retrofitting as modifying existing structures to increase resistance. Key techniques mentioned include adding new shear walls, steel bracing, column and beam jacketing with steel or concrete, base isolation using seismic isolators, mass reduction by removing floors, and wall thickening. The document also discusses challenges in retrofitting and standards from Indian codes for earthquake-resistant design. The conclusion emphasizes that retrofitting has matured but expertise is still lacking, and optimization is needed to determine the most cost-effective technique for a given structure.
This document provides an introduction and manual for the design of hollow core slabs. It discusses the manufacturing of hollow core slabs and the materials used. It then covers advantages of hollow core slabs and common framing concepts. The bulk of the document focuses on guidelines for designing hollow core slabs, including flexural and shear design, camber and deflection, composite design, and strand development. It also covers special design considerations like load distribution, effects of openings, continuity, and cantilevers. Finally, it discusses using hollow core slabs as diaphragms to resist lateral loads. The manual is intended to provide design guidance and reference material for engineers and producers working with hollow core slab systems.
The construction industry worldwide needs innovative materials to resolve many longstanding issues such as reinforcement corrosion and concrete deterioration.
Glass fiber reinforced polymer (GFRP) rebars were inadvertently discovered in 1967 and have since become a staple in the building industry. GFRP rebars provide a non-corrosive alternative to steel rebar that increases the service life of concrete structures. They are impervious to chloride ions and chemical attacks, have greater tensile strength than steel, are only 1/4 the weight, and are transparent to magnetic fields. GFRP rebars have hundreds of applications in concrete structures in North America, including interior and exterior uses such as columns, panels, roofs, and more.
METHODS OF RETROFITTING EARTHQUAKE DAMAGESUmer Farooq
The primary purpose of earthquake retrofitting is to keep a home from being displaced from its concrete foundation. Retrofitting means making improvements to an existing building. The purpose is to make the building safer and less prone to major structural damage during an earthquake. Existing homes need to be retrofitted because our understanding of the effects of earthquakes as well as construction techniques have improved after the homes were built. The terms house bolting, foundation bolting and cripple wall bracing are often used synonymously with earthquake retrofitting
This document discusses various techniques for retrofitting existing structures to improve their resistance to seismic activity. It describes adding new shear walls, steel bracing, or jacketing columns as common retrofitting methods. Base isolation, which isolates the structure from foundations, is also discussed. The objectives of retrofitting are outlined as increasing strength, ductility, and protecting life safety. Different classification of retrofitting techniques are provided based on addressing local deficiencies or global irregularities.
Effect of infill walls on the seismic performance of the multistoried buildingseSAT Journals
Abstract The most commonly used structural system in our country for almost all types of building are multi-storey reinforced concrete frames with masonry infills. Therefore it is essential to understand the seismic behaviour of these structures when subjected to lateral forces. Several research works has been done on the masonry infilled reinforced concrete frames in the past decades. Mortar is used as a binder in normal brick construction in order to create continuous structural form and to bind together the individual units in brickwork. In the present study, analysis has been carried out by considering the increase in height of building from five to ten storied by using finite element software ANSYS 14.5. The seismic analysis of multi-storeyed building frames with infill walls and without infill walls are conducted. 3D analysis will give more realistic values of deflection and stresses. Since this type of study is not feasible in terms of analysis time taken, 2D model was adopted for the present study. A three bay two dimensional building frame is considered with the number of stories varying from 5 storied to 10 storied. The loading applied is as per IS 1893 (Part I): 2002. Equivalent diagonal strut method is adopted for modelling infill walls. The results showed that there is considerable decrease in deflection when infills are used in RC frames. Key Words: Deflection , Equivalent diagonal strut method, lateral load, Solid brick infills, Storey drift
Seismic retrofitting is the modification of existing structures to make them more resistant to seismic activity, ground motion, or soil failure due to earthquakes.
CE 72.52 - Lecture 8b - Retrofitting of RC MembersFawad Najam
This document contains a presentation by Dr. Pramin Norachan on fiber reinforced polymer (FRP) systems for strengthening concrete structures. The presentation covers flexural, shear, axial and confinement strengthening using FRP. It discusses various FRP materials, design considerations, and design equations. The key points covered include the materials and properties of FRP, how FRP is used to enhance load capacity, ductility and durability of structures, and design approaches for flexural, shear and confinement strengthening.
This Presentation covers the technique of retrofitting of existing as well as worn out structures using FRP laminates. Thermal stresses are imposed into the samples to mimic fire in a building. It is then tested for strength, repaired using 250 gsm glass fiber reinforced polymer and then tested for strength again. It was observed that the lost strength of the samples subjected to thermal stresses was regained.
Strengthening structures via external bonding of advanced fibre reinforced polymer (FRP) composite is becoming very
popular worldwide during the past decade because it provides a more economical and technically superior alternative
to the traditional techniques in many situations as it offers high strength, low weight, corrosion resistance, high fatigue
resistance, easy and rapid installation and minimal change in structural geometry. Although many in-situ RC beams
are continuous in construction, there has been very limited research work in the area of FRP strengthening of continuous
beams.
Strengthening Of Beams for flexure Using FRPReham fawzy
This document discusses fiber reinforced polymer (FRP) composites used for strengthening concrete structures. It covers various topics such as FRP materials and systems, causes of structural defects, strengthening techniques, and design considerations. Specifically, it describes the different types of fibers and matrices used in FRP, advantages of FRP over traditional materials, and applications of FRP like flexural, shear, and axial strengthening of beams, columns, slabs and walls. It also identifies potential structural defects in design, construction or over the service life of a structure that could require strengthening.
Repair and Retrofit on Beam and Column Jointsamerald24
A research experiment has been conducted on the structural performance of repaired minor damaged reinforced concrete beam and column Joints using composite known as CFRP (Carbon Fiber Reinforced Polymer) under simulated cyclic 2D loadings to find the practical lamination repair scheme for flexural strengthening, shear strengthening, and joint strengthening.
This document summarizes research on strengthening reinforced concrete beams using fiber reinforced polymer (FRP) sheets. It discusses how FRP strengthening has become a popular technique worldwide due to advantages like high strength, light weight, corrosion resistance, and easy installation. The document reviews literature on strengthening both simply supported and continuous beams. It outlines different FRP strengthening methods and discusses factors that influence the behavior and failure of strengthened beams, such as surface preparation, adhesive type, and concrete strength. The document also discusses design considerations and challenges for FRP strengthening, as well as disadvantages like lack of design codes and fire risk.
This document discusses retrofitting techniques to strengthen existing structures against seismic activity. It describes upgrading reinforced concrete and masonry structures through methods like reinforced concrete jacketing, steel plate bonding, and adding new structural elements. Recent trends in Pakistan involve using carbon fiber reinforced polymer composites for flexural and shear strengthening. The document provides examples of retrofitting projects completed in Pakistan using these composite systems.
The document discusses retrofitting of reinforced concrete beam-column joints through various techniques like jacketing, case studies, and concludes with key findings. Specifically, it summarizes three case studies: 1) Retrofitting using reinforced concrete jacketing improved strength and ductility over the brittle original joint. 2) Using carbon fiber reinforced polymer on a damaged joint improved shear strength and ductility. 3) Glass fiber reinforced polymer wrapping a joint improved its shear and bond-slip resistance, producing more ductile failures in beams.
This document is a project report on the design of a shear wall using STAAD Pro software. It includes an introduction to shear walls, which are vertical structural elements that resist lateral loads like wind and earthquakes. The report discusses the purpose, applications, advantages, and disadvantages of shear walls. It also describes the different types of shear walls and their behavior under loads. The design procedure for shear walls in STAAD Pro and as per reference codes is explained. The conclusion summarizes that shear walls provide strength and stiffness to resist lateral loads in buildings.
This document discusses materials used for repairing and rehabilitating reinforced concrete structures. It covers various repair strategies like load reduction, crack repair, and strengthening of structural elements. It also discusses different types of materials used for surface preparation, corrosion protection, bonding, structural repairs, and other purposes. Key materials mentioned include cement mortars, polymer-modified cement products, epoxies, acrylics, and chemicals. The document provides guidelines on selecting appropriate materials based on properties like shrinkage, bond strength, thermal expansion, and durability. It also outlines various applications of polymer mortars and epoxies in structural repair and rehabilitation work.
This document discusses smart concrete invented by Professor Deborah Chung. Smart concrete is concrete that can sense its own strain or stress without embedded sensors. It has been modified with admixtures so that changes in electrical resistance allow it to function as a sensor. Two types were studied: one with short carbon fibers and one with carbon nanotubes. Laboratory experiments showed that when molded into squares with electrodes, both types demonstrated piezoresistive properties and were able to detect internal stress and strain, showing potential as sensors for pavement monitoring.
retrofitting of fire damaged rcc slabs,colums,beamsNayana 54321
This document discusses techniques for retrofitting existing reinforced concrete structures. It introduces various problems that can occur in concrete structures like damage, excessive loading, cracks, and corrosion. Retrofitting aims to restore strength and improve serviceability. Factors influencing the selection of a retrofitting technique include cost, time constraints, and existing structure conditions. Conventional techniques discussed are section enlargement, external plate bonding, external post-tensioning, ferrocement covering, and grouting. An advanced technique of fiber reinforced polymer composites is also introduced, with carbon fiber reinforced polymer being highlighted. CFRP has advantages of high strength, corrosion resistance, and suitability for seismic retrofitting but also has high initial costs.
This document discusses various techniques for retrofitting concrete structures to make them more resistant to seismic activity and other natural hazards. It defines retrofitting as modifying existing structures to increase resistance. Key techniques mentioned include adding new shear walls, steel bracing, column and beam jacketing with steel or concrete, base isolation using seismic isolators, mass reduction by removing floors, and wall thickening. The document also discusses challenges in retrofitting and standards from Indian codes for earthquake-resistant design. The conclusion emphasizes that retrofitting has matured but expertise is still lacking, and optimization is needed to determine the most cost-effective technique for a given structure.
This document provides an introduction and manual for the design of hollow core slabs. It discusses the manufacturing of hollow core slabs and the materials used. It then covers advantages of hollow core slabs and common framing concepts. The bulk of the document focuses on guidelines for designing hollow core slabs, including flexural and shear design, camber and deflection, composite design, and strand development. It also covers special design considerations like load distribution, effects of openings, continuity, and cantilevers. Finally, it discusses using hollow core slabs as diaphragms to resist lateral loads. The manual is intended to provide design guidance and reference material for engineers and producers working with hollow core slab systems.
The construction industry worldwide needs innovative materials to resolve many longstanding issues such as reinforcement corrosion and concrete deterioration.
Glass fiber reinforced polymer (GFRP) rebars were inadvertently discovered in 1967 and have since become a staple in the building industry. GFRP rebars provide a non-corrosive alternative to steel rebar that increases the service life of concrete structures. They are impervious to chloride ions and chemical attacks, have greater tensile strength than steel, are only 1/4 the weight, and are transparent to magnetic fields. GFRP rebars have hundreds of applications in concrete structures in North America, including interior and exterior uses such as columns, panels, roofs, and more.
METHODS OF RETROFITTING EARTHQUAKE DAMAGESUmer Farooq
The primary purpose of earthquake retrofitting is to keep a home from being displaced from its concrete foundation. Retrofitting means making improvements to an existing building. The purpose is to make the building safer and less prone to major structural damage during an earthquake. Existing homes need to be retrofitted because our understanding of the effects of earthquakes as well as construction techniques have improved after the homes were built. The terms house bolting, foundation bolting and cripple wall bracing are often used synonymously with earthquake retrofitting
This document discusses repairs, rehabilitation, and retrofitting of structures. It begins by defining repair, rehabilitation, and retrofitting. Repair returns a structure to its previous condition without improving strength. Rehabilitation considers strength by repairing damage. Retrofitting modifies existing structures to increase resistance to hazards like earthquakes. It provides examples of each process. The document outlines evaluation and quality control methods for repairs. It also discusses materials and techniques used for crack repair in structures, including epoxy injection grouting. Overall, the document provides an overview of restoring and upgrading structures through various repair, rehabilitation, and retrofitting methods.
The document discusses seismic retrofitting of buildings to make them more resistant to earthquakes. It describes how seismic retrofitting includes strengthening structural elements like connections, walls, and foundations. It outlines several methods for retrofitting such as adding new structural elements like walls, using innovative materials like fiber reinforced plastics, implementing base isolation systems, and supplemental energy dissipation. The document provides details on evaluating seismic vulnerability and the need for retrofitting to improve building safety, reduce hazards, and limit losses from earthquakes.
Retrofitting of RCC structural members is necessary to prevent further distress in concrete. Retrofitting of RCC members should start with investigation and diagnosis of cracks and then by applying suitable retrofitting measures.
ABSTRACT
Ferrocement addition in cement mortar or concrete increases the performance of material. The present paper describes the results of testing flat ferrocement panels reinforced with different number of wire mesh layers. The main objective of these experimental tests is to study the effect of using different numbers of wire mesh layers on the flexural strength of flat ferrocement panels and to compare the effect of varying the number of wire mesh layers on the ductility and the ultimate strength of these types of ferrocement structures.
The used number of wire mesh layers is one, two, three and four layers.
The experimental results show that flexural strength of the folded panels increased by 37% and 90% for panels having 2 and 3 wire mesh layers respectively, copared with that having single layer, while for flat panel the increase in flexural strength compared with panel of plan mortar is 4.5%, 65% and 68% for panels having 1, 2 and 3 wire mesh layers respectively. The strength capacity of the folded panels, having the particular geometry used in the present study, is in the order of 3.5 to 5 times that of the corresponding flat panels having the same number of wire mesh layers. Both types are also analyzed using finite element method to check the flexural stresses in these panels under self weight and cracking load.
Keywords: Ferrocement, Flat Panel, Mortar, Wire Mesh.
Ferrocement is a thin reinforced concrete construction where wire meshes are embedded in cement mortar. It was developed by Italian architect P.L. Nervi in 1940. Ferrocement provides benefits such as low self-weight, lack of need for skilled workers, no formwork requirement, low maintenance costs, and versatility in shapes. Some drawbacks include vulnerability to punctures and corrosion of reinforcing materials. Ferrocement construction is suitable for housing, marine, agricultural, and industrial applications in developing countries due to use of locally available materials, low capital requirements, and less need for heavy machinery. While still developing, ferrocement shows promise as an economical construction material.
retrofitting of existing rcc members Different strengthening techniquessuraj prasanna kumar
This document discusses different techniques for retrofitting existing reinforced concrete (RCC) structures. It begins by introducing the problems that can occur in RCC structures like damage, excessive loading, and seismic damage. It then discusses factors to consider when deciding between retrofitting versus reconstruction. Several conventional retrofitting techniques are described such as section enlargement, external plate bonding, and grouting. The document focuses on fiber reinforced polymer (FRP) composites as an advanced technique, describing how carbon FRP is used to wrap or apply strips to structural members to improve strength, ductility, corrosion resistance, and seismic performance in a minimally invasive manner.
Ferrocement is a thin reinforced concrete made of cement mortar and wire mesh. It is strong, durable, and low-cost. Common applications include walls, floors, roofs, water tanks, bridges, and marine structures. Ferrocement is 2-5 cm thick and has a cement mortar mix reinforced with steel mesh or rods. It was invented in the 1850s and methods of construction include skeletal armature, closed mould, integral mould, and open mould. Ferrocement is used Residential buildings, marine applications, water and sanitation infrastructure, agriculture, renewable energy, and other structures.
FERROCRETE - MATERIAL AND CONSTRUCTION METHODSjagrutib22
Ferrocrete is a type of reinforced concrete that uses closely spaced wire mesh or small diameter rods infiltrated with mortar. It has high density and durability to withstand various climates. Ferrocrete structures are lighter than regular reinforced concrete and do not require formwork. Some applications of ferrocrete include roofing, water tanks, bridges, and precast building components. Ferrocrete is constructed by first making a wire mesh framework, applying mortar that is worked into the mesh, and compacting it. This produces a strong, lightweight material suitable for many construction applications.
1. Concrete repair refers to modifying damaged concrete structures to restore their load-bearing capacity and durability.
2. Common repair techniques include removing damaged concrete and replacing it with new concrete.
3. Shotcreting is a repair method that projects a concrete mixture at high velocity to repair large areas or strengthen structures. It produces a dense, homogeneous material without formwork.
The document provides guidelines for repair and rehabilitation of existing reinforced concrete buildings. It discusses causes of concrete deterioration like permeability, aggressive agents, and condition surveys. Non-destructive tests are recommended to evaluate concrete quality, cracking, and corrosion. The approach involves identifying deterioration causes, assessing damage extent, and selecting appropriate repair materials and methods to rehabilitate structures in a systematic and cost-effective manner.
The document discusses various aspects of waterproofing systems. It explains that conventional waterproofing involves applying membrane barriers to prevent water passage. It also notes that quality waterproofing is essential to preserve building envelope water-tightness, as below-grade areas and plaza decks experience hydrostatic pressure. The document then provides definitions for waterproofing versus damp-proofing and discusses different waterproofing materials and methods, including sheet membranes, liquid systems, bentonite, metal oxide, and cementitious options. It emphasizes that substrate preparation and multiple protective layers are important for effective waterproofing.
FRP (fiber reinforced polymers) are a composite material made of fibers encapsulated in a polymer resin matrix. They are used for structural strengthening and repair in construction. FRP provides high tensile strength along the fiber orientation and the resin provides stability, shear strength, and bonding to the substrate. Common fiber types include carbon, glass, and aramid. FRP has advantages over conventional repair methods as it is lightweight, corrosion resistant, and can be applied in occupied spaces. Applications include seismic retrofitting of columns, beams and walls, repairing deteriorated concrete, and strengthening structures like bridges and industrial facilities. FRP installation involves surface preparation, applying primer, saturating fabric with resin, and allowing it to cure. FRP
This document provides guidelines for ductile detailing of reinforced concrete structures subjected to seismic forces. Some key points:
- It covers requirements for designing and detailing reinforced concrete buildings to have adequate toughness and ductility during earthquakes.
- Provisions include constraints on member dimensions, reinforcement ratios and placement, splice locations, and special confinement in potential plastic hinge regions.
- Shear walls, coupling beams, and joints are to be designed and detailed to dissipate seismic energy in a stable manner through extensive inelastic deformations.
Ecofriendly christmas gifting ideas for CorporatesUsha Mallya
This document provides eco-friendly corporate gifting ideas for Christmas, including jute pouches, bags, and wine bottle holders, as well as baskets made from bamboo, palm leaves, and banana leaves. It also lists aroma candle sets as an option and provides contact information for Usha Mallya to discuss environmentally conscious gift options.
The document summarizes an experimental study on using carbon fiber reinforced polymer (CFRP) sheets to rehabilitate and strengthen reinforced concrete beams. Twelve beams were fabricated and strengthened with different CFRP configurations. Beams were loaded to different magnitudes prior to strengthening to study the effect of initial loading. Beams were then retrofitted with one or two CFRP layers and reloaded until failure. Results showed shear strength increased significantly with CFRP sheets. Orienting the sheets at 45 degrees was most effective. The literature review discussed previous research on using CFRP to strengthen beams in flexure and shear. Parameters like CFRP amount and configuration affected failure modes and structural performance.
In the last ten years or a little more, CFRP strips and fabrics have been successfully externally bonded to rehabilitate the concrete structures. Most of the previous research focused on the use of CFRP as an enhanced material to improve flexural, shear, ductility and ductility behaviour and confinement of concrete structural members, while limited attention was paid to the investigation of strengthened reinforced concrete (RC) members against torsion, particularly continuous concrete beams. This study aims to detect experimentally the CFRP strengthening technique for continuous RC beams exposed to pure torsion. The experimental program includes investigation of two groups of beams; the first group was composed of twelve un-strengthened beam specimens and the second one includes a total of twelve strengthened beam specimens; all were experienced under pure torsion. Factors considered in the testing program included the effects of concrete compressive strength and the angel of a twist. The angle of twist at each level of force applications, torque at first crack, ultimate torque was to be in comparison with for control and strengthened beams. The outcomes of the tests indicated that all beams wrapped with CFRP fabrics resulted in improvement in tensional resistance as compared with the reference specimens.
This document presents an analytical model to simulate a single story brick masonry in-filled frame strengthened with carbon fiber reinforced polymer (CFRP) to resist lateral loads. The model is based on experimental testing of half-scale in-filled frame specimens with different CFRP strengthening techniques. The analytical model represents the in-filled frame as diagonal struts acting in compression. Based on this model, the document derives two formulas to determine the required amount of CFRP to resist lateral loads - an accurate solution and a simplified empirical design equation. Both formulas showed good agreement with results from the experimental testing.
Analytical Model and Design Guidelines for Using FRP System in Strengthening In-filled Frames
The document presents an analytical model for simulating a single story brick masonry in-filled frame strengthened with carbon–fiber reinforced polymer (CFRP) sheets or strips. The model represents the masonry wall as a diagonal compression strut and the CFRP as a diagonal tension tie. Two equations are derived from the model: one calculates the required CFRP force and a simplified equation for preliminary design. Both equations showed good agreement with experimental test results on CFRP-strengthened in-filled frames.
Flexural Analysis of RC Beam Strengthened with Side Near Surface Mounted-CFRP...IRJET Journal
1) The document analyzes the flexural behavior of reinforced concrete beams strengthened with side near surface mounted carbon fiber reinforced polymer (CFRP) techniques through analytical, numerical, and experimental methods.
2) Finite element analysis software ANSYS was used to numerically model beam geometry and compare results with hand calculations. The results showed good agreement between analytical and numerical methods.
3) The study found that strengthening RC beams with side near surface mounted CFRP rebar and strips led to a significant reduction in beam deflection compared to unstrengthened beams. It also analyzed parameters like flexural strength, shear capacity, strain energy, stresses, and strains.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
An Analytical Study on Static and Fatigue Analysis of High Strength Concrete ...Stephen Raj
In recent years FRP stands as a better alternative to restore and upgrade deficient structures. The deficiency may be due to change in design standards, improper construction practices (or) adverse environmental conditions. Under such circumstances, adoption of appropriate technique for restoring the structure becoming challenging task. The objective of this thesis work is to evaluate the static and fatigue response of HSC beams with externally bonded FRP laminates using ANSYS software. The modeling and analysis is done using the software for HSC beam. The beams were strengthened with FRP laminates. The models are provided with carbon types of Fiber Reinforced Polymer (FRP) laminates. The available experimental data of HSC beam in flexure behavior is the source material of this analysis work. All the relevant data are taken from that source material. The static and fatigue load cases are applied and the results are discussed. The comparison is made between the available experimental results of HSC beam with analytical based results of HSC beam.
This document reviews 10 articles on carbon fiber reinforced polymer (CFRP) strengthened reinforced concrete beams. The articles studied parameters like CFRP orientation, anchorage techniques, beam dimensions, and fiber direction. Tests showed that CFRP increased beam shear capacity and flexural strength when anchored properly to prevent premature debonding. Larger beams saw less improvement from CFRP sheets due to size effects. Orienting CFRP fibers at 45 degrees perpendicular to cracks optimized shear strengthening.
Numerical Study on Retrofitting Of Beam Column Joint Strengthened With CFRPIRJET Journal
This document presents a numerical study on retrofitting an exterior beam-column joint with carbon fiber reinforced polymer (CFRP). A finite element model of an unstrengthened joint and a joint strengthened with CFRP wrapping is created in ANSYS. The models are subjected to cyclic loading and their stress distributions and deformations are analyzed and compared. The results show that strengthening the joint with CFRP increases its structural stiffness, strength, and energy dissipation capacity. The load-carrying capacity of the strengthened joint is 30% higher than the unstrengthened joint. CFRP wrapping is an effective rehabilitation technique for improving the seismic performance of damaged reinforced concrete beam-column joints.
COMPARATIVE STUDY ON RETEROFITTING OF RCC BEAM AND COLUMN JOINT BY USING FERR...IRJET Journal
This document summarizes research on retrofitting reinforced concrete beam-column joints using ferrocement, glass fiber reinforced polymer (GFRP), and carbon fiber reinforced polymer (CFRP). It presents the methodology, results, and conclusions of finite element modeling conducted using ANSYS. The modeling analyzed exterior beam-column joints under different retrofitting conditions: without retrofitting, with ferrocement, with GFRP, and with CFRP. The results showed that retrofitted joints had 30% higher load carrying capacity and improved load-deformation behavior compared to unretrofitted joints. Specifically, CFRP retrofitting shifted the failure from the column to the beam, preventing progressive collapse. In conclusion, fiber-reinforced polymer
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1. The document discusses strengthening of reinforced concrete (RC) beams with externally bonded glass fiber reinforced polymers (GFRPs).
2. Shear failure of RC beams is identified as a disastrous failure mode, and GFRP composites have become a popular technique for shear strengthening due to advantages like high strength and corrosion resistance.
3. The document reviews several studies that have examined using GFRP wraps, strips, and grids for shear strengthening RC beams, finding they can increase shear capacity significantly.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
EFFECT OF CARBON LAMINATION ON THE STRENGTH OF CONCRETE STRUCTURESIAEME Publication
This work consists of preparation and testing of different structural model like cubes, Beams and Columns. They are tested for Compression test, Flexural test and Split tensile Test. The comparison between Laminated and un-laminated Structural Models was made in order to know how much strength gain after testing of these structural models, so by which the rehabilitation of any structure can be done without demolishing it with less weight to strength ratio.
Strengthening of Masonry Structures: A ReviewIRJET Journal
1) The document discusses techniques for strengthening masonry structures, including fibre reinforced polymer (FRP), engineered cementitious composite (ECC), and geotextiles.
2) Different types of FRPs like carbon, glass, and basalt are explored for their ability to enhance structural strength when applied to masonry.
3) Near surface mounted (NSM) FRP and continuous FRP overlays are highlighted as effective techniques for improving load capacity and ductility of masonry walls.
This document discusses strengthening concrete beams using fiber reinforced polymer (FRP). It begins with an introduction to FRP, including its history and advantages over traditional materials. Methods of strengthening beams for flexure using externally bonded FRP are then described. Design considerations like failure modes, stress-strain relationships, and ensuring bond are discussed. Strengthening calculations and variables in FRP composite design are also covered at a high level.
State-of-the-art review of FRP strengthened RC slabsIJSRD
1) The document reviews different techniques for strengthening reinforced concrete slabs using fibre reinforced polymers (FRP), including externally bonded reinforcement and near surface mounted reinforcement.
2) It summarizes the advantages of FRP including corrosion resistance, ease of installation, and simplicity, and discusses how FRP can be used to strengthen beams, columns, and slabs.
3) The literature review found that FRP is effective at increasing load capacity of slabs with openings when used to strengthen, though debonding is a risk, and other techniques like steel plates can provide some strengthening but are limited.
Beam-Column joints are critical regions in reinforced con
which are most vulnerable or sensitive to seismic forces. Hence strengthening and
rehabilitant beam-column joint is imperative to save the structure and its inhabitants
in case of earthquake forces. Numerous and large scale retrofit
reinforced polymer (FRP) composites are being undertaken worldwide. This
experimental study aims to investigate the effectiveness of strengthening beam
joints using synthetic fibres. In this study, Aramid fiber (synthetic fibr
strengthening and rehabilitant of beam
and tested under monotonic loading with the help of universal testing machine. At the
end, test results of control and rehabilitated samples were compared t
experimental conclusions in all tested specimens will embolden future investigations
in same direction for long term performance to enhancing this AFRP in structural
applications.
IRJET- Strengthening of Column using CFRPIRJET Journal
This document discusses strengthening concrete columns using carbon fiber reinforced polymer (CFRP) wrapping. It first provides background on CFRP, including its advantages over other fiber reinforced polymers like aramid and glass. The document then discusses an study that aims to investigate the effects of wrapping reinforced concrete columns with CFRP. In the study, some columns will be unwrapped control specimens while others will be wrapped with CFRP. Parameters like the number of CFRP layers and the compressive strength of the original concrete will be varied. The results will be analyzed to determine how CFRP wrapping affects factors like failure mode, ultimate load capacity, and strength of the columns. The goal is to evaluate if CFRP wrapping can effectively
IRJET- Flexural Behaviour of Reinforced Concrete Beams Retrofitted with Fibre...IRJET Journal
This document summarizes an experimental study that tested reinforced concrete beams retrofitted with different combinations of carbon fiber reinforced polymer (CFRP) and glass fiber reinforced polymer (GFRP) sheets. Thirty-six beams were tested with variations in the number of layers (two or three) and sequence of the fiber sheets applied. The results showed that the strengthening effects on ultimate strength and ductility depended on the order of the fiber layers. Beams retrofitted after being preloaded to 70% of their capacity also exhibited improvement, demonstrating FRP retrofitting is effective for damaged structures.
Introduction- e - waste – definition - sources of e-waste– hazardous substances in e-waste - effects of e-waste on environment and human health- need for e-waste management– e-waste handling rules - waste minimization techniques for managing e-waste – recycling of e-waste - disposal treatment methods of e- waste – mechanism of extraction of precious metal from leaching solution-global Scenario of E-waste – E-waste in India- case studies.
Comparative analysis between traditional aquaponics and reconstructed aquapon...bijceesjournal
The aquaponic system of planting is a method that does not require soil usage. It is a method that only needs water, fish, lava rocks (a substitute for soil), and plants. Aquaponic systems are sustainable and environmentally friendly. Its use not only helps to plant in small spaces but also helps reduce artificial chemical use and minimizes excess water use, as aquaponics consumes 90% less water than soil-based gardening. The study applied a descriptive and experimental design to assess and compare conventional and reconstructed aquaponic methods for reproducing tomatoes. The researchers created an observation checklist to determine the significant factors of the study. The study aims to determine the significant difference between traditional aquaponics and reconstructed aquaponics systems propagating tomatoes in terms of height, weight, girth, and number of fruits. The reconstructed aquaponics system’s higher growth yield results in a much more nourished crop than the traditional aquaponics system. It is superior in its number of fruits, height, weight, and girth measurement. Moreover, the reconstructed aquaponics system is proven to eliminate all the hindrances present in the traditional aquaponics system, which are overcrowding of fish, algae growth, pest problems, contaminated water, and dead fish.
A review on techniques and modelling methodologies used for checking electrom...nooriasukmaningtyas
The proper function of the integrated circuit (IC) in an inhibiting electromagnetic environment has always been a serious concern throughout the decades of revolution in the world of electronics, from disjunct devices to today’s integrated circuit technology, where billions of transistors are combined on a single chip. The automotive industry and smart vehicles in particular, are confronting design issues such as being prone to electromagnetic interference (EMI). Electronic control devices calculate incorrect outputs because of EMI and sensors give misleading values which can prove fatal in case of automotives. In this paper, the authors have non exhaustively tried to review research work concerned with the investigation of EMI in ICs and prediction of this EMI using various modelling methodologies and measurement setups.
Presentation of IEEE Slovenia CIS (Computational Intelligence Society) Chapte...University of Maribor
Slides from talk presenting:
Aleš Zamuda: Presentation of IEEE Slovenia CIS (Computational Intelligence Society) Chapter and Networking.
Presentation at IcETRAN 2024 session:
"Inter-Society Networking Panel GRSS/MTT-S/CIS
Panel Session: Promoting Connection and Cooperation"
IEEE Slovenia GRSS
IEEE Serbia and Montenegro MTT-S
IEEE Slovenia CIS
11TH INTERNATIONAL CONFERENCE ON ELECTRICAL, ELECTRONIC AND COMPUTING ENGINEERING
3-6 June 2024, Niš, Serbia
Embedded machine learning-based road conditions and driving behavior monitoringIJECEIAES
Car accident rates have increased in recent years, resulting in losses in human lives, properties, and other financial costs. An embedded machine learning-based system is developed to address this critical issue. The system can monitor road conditions, detect driving patterns, and identify aggressive driving behaviors. The system is based on neural networks trained on a comprehensive dataset of driving events, driving styles, and road conditions. The system effectively detects potential risks and helps mitigate the frequency and impact of accidents. The primary goal is to ensure the safety of drivers and vehicles. Collecting data involved gathering information on three key road events: normal street and normal drive, speed bumps, circular yellow speed bumps, and three aggressive driving actions: sudden start, sudden stop, and sudden entry. The gathered data is processed and analyzed using a machine learning system designed for limited power and memory devices. The developed system resulted in 91.9% accuracy, 93.6% precision, and 92% recall. The achieved inference time on an Arduino Nano 33 BLE Sense with a 32-bit CPU running at 64 MHz is 34 ms and requires 2.6 kB peak RAM and 139.9 kB program flash memory, making it suitable for resource-constrained embedded systems.
Using recycled concrete aggregates (RCA) for pavements is crucial to achieving sustainability. Implementing RCA for new pavement can minimize carbon footprint, conserve natural resources, reduce harmful emissions, and lower life cycle costs. Compared to natural aggregate (NA), RCA pavement has fewer comprehensive studies and sustainability assessments.
Literature Review Basics and Understanding Reference Management.pptxDr Ramhari Poudyal
Three-day training on academic research focuses on analytical tools at United Technical College, supported by the University Grant Commission, Nepal. 24-26 May 2024
Literature Review Basics and Understanding Reference Management.pptx
Retrrofitting
1.
2. The discussion is divided into following
section:
1.Objective of research
2.What is retrofitting
3.What is Ferrocement,Why Ferorocement is suitable for
retrofitting
3.Methodology of ferrocement retrofitting
4.What is FRP ,Why FRP is suitable for retrofitting,Methodology
of FRP retrofitting
5. Comparative study on Ferrocement and FRP …Which process
is more effective and economical??
3. Retrofitting of the existing structures has become a large part
of the construction activity. Columns are the most
authoritative structural element in any structure that transfers
the entire loads to the foundation. strengthening of deficient
columns is necessary to increase the load carrying capacity,
ductility and energy absorption capacity that can be achieved
by external confinement of column. External confinement can
be done by retrofitting……
The main objective of the experimental program is to study
the behavior of reinforced concrete short columns subjected
to axial load and flexure strengthened with Ferrocement and
Fiber reinforcement polymer. And to observe which process
is better for our country considering both economical and
seismic strength
4. Upgrading of certain building system (existing structures) to make
them more resistant to seismic activity such as earthquake resistance
Structure can be:
-Earthquake damaged
-Earthquake vulnerable
Retrofitting of Column and Beam
5. Due to damages by earthquake, changes in codes, rezoning of
seismic intensity, poor detailing practice, and wrong design et
al, many existing reinforced concrete buildings are seismically
deficient. A large number of existing buildings and bridges
have indicated that the major deficient of reinforced. The lack
of sufficient transverse reinforcement in short columns may
lead to a brittle shear failure due to inadequate shear strength
under earthquake which clearly demonstrated a need for their
retrofit.
Retrofitting proves to be a better economic consideration and
immediate shelter to problems rather than replacement of
building
6.
7. There are considerable number of reinforcement concrete structure
in Bangladesh, which do not meet the correct design standard
because of inadequate design or construction error (such as Rana
Plaza).
8. After recent earth quake and Rana plaza disester
the need of structural upgrading specially to meet
seismic design requirement should increase .And
for existing structure of Bangladesh retrofitting is
the best solution.
And in our country there is a notion that
retrofitting is very expensive and it is not viable for
economy like Bangladesh. But it is totally wrong.
Usually it only costs 10-30 percent of new
construction
9. Recently JICA (Japan International Cooperation Agency) start
working in Bangladesh to make earthquake-resistant
structure by systematic retrofitting .And JICA team expert
says The retrofitting works will have a positive impact on
Bangladesh.
10.
11. An FRP composite is defined as a polymer that is reinforced
with a fiber. The primary function of fiber reinforcement is to
carry load along the length of the fiber and to provide strength
and stiffness in one direction. FRP represents a class of
materials that falls into a category referred to as composite
materials, The fibers are usually glass, carbon, or aramid,
although other fibers such as paper or wood or asbestos have
been sometimes used.
Fiber reinforced polymer (FRP) are used in advanced
civil engineering structure such as Building ,Bridges
etc.
12. Strengthening of Columns:
The repair and strengthening of reinforced concrete (RC) columns through FRP
composites includes external FRP wrapping, FRP encasement, and FRP spraying.
Columns can be strengthened to increase the axial, shear, and flexural capacities for
a variety of reasons such as lack of confinement,
eccentric loading, seismic loading, accidental impacts, and corrosion. In the
following sections, these
topics are discussed in further detail.
FRP encasement FRP wrapping FRP spraying
13. FRP used to increase the axial load carrying
capacity of the column with minimal increase in the
cross-sectional area. Confinement consists of
wrapping the column with FRP sheets ,The use of
confinement increases the lateral pressure on the
member which results in more ductility and higher
load capacity.
14. Carbon fiber has very high tensile strength and is
also very lightweight. When bonded to the exterior
of a concrete column, beam, or slab
Carbon fiber reinforcement polymer
15. Carbon fiber reinforcement polymer can add significant
strength without adding weight that would increase the
load on foundations and other structural members.
CFRP wraps are easy to apply and can be used on any
size or shape of structural member.
CFRP wrapping
16. Ferro cement jacketing is one of the alternate
method of repair and strengthening of column
which is low cost and easy to apply to existing
column.
17. Advantages of ferrocement are high ductility, reduce number of cracks
and crack width, high
deformation capacity, improve impact resistance and toughness, good
fire resistance, low
permeability, low cost of maintenance and high strength to weight ratio.
18. Ferrocement confined columns are constructed with
ferrocement as a skin on the periphery surface. These skins
consist of layers of wire mesh. Due to its better crack
arresting property and high ductility this arrangement
increases the resistance to bending moment, shear, and
torsion
19. Comparison between Frp and Ferrocement retrofitting:
CFRP is thus not primarily a load carrying member,but its
geometric properties will beneficially affect the elastic
buckling of the section. This is also congruent with the fact
that the CFRP is not extended to the end of the specimens
and is not in contact with the loading platens of the
machine, and is thus not directly carrying axial load.
The study was of Ferrocement able to predict ultimate
flexural capacity and deflections and crack widths
ferrocement beams under loading. The study also observed
the load-deflection curves, crack distribution, and crack
widths for ferrocement beams up to ultimate. From test
measurement of stress-strain curves for mortar in
compression (including the descending portion) and steel
meshes in tension, an analytical model was developed to
generate the nonlinear moment-curvature and load-
deflection curves of ferrocement beams.