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fiber-reinforced-plastics
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Total 62 records
Fracture Modeling of Strengthened Arc Concrete Structures with FRP by Concrete Damage Plasticity and XFEM
, M.Sc. Thesis Sharif University of Technology ; Khoei, Amir Reza (Supervisor)
Abstract
Usage of FRP material is developed in recent year, because advantages of this material researcher studied the effect of this strengthening method on beam column and masonry structures, but few research’s related to RC arches that strengthen with FRP. This studies showed performance of structure properties but many parameters influence. In this research, a model developed that can model RC arch with FRP till complete failure, after verifying model with experimental result parametric study done. This parameter are effect of strengthening scheme, influence of shape of arch and geometry of arches. Concrete damage plasticity used for modeling behavior of concrete, also for modeling interface...
Investigation of Dynamic Behavior of Concrete Slabs Reinforced with GFRP Bars and Prestressed Concrete Slabs under Impact Loading
, Ph.D. Dissertation Sharif University of Technology ; Khaloo, Alireza (Supervisor)
Abstract
Prestressed and reinforced concrete slabs are common structural elements that could be exposed to impact loading. Although, use of reinforced concrete slabs and utilization of Fiber Reinforced Polymer (FRP) as alternative to traditional steel reinforcement slabs are growing, but the influence of various parameters on their response under impact loads is not properly evaluated. In addition, studies on steel reinforced concrete slabs have been found in literature, but investigation of prestressed slabs and GFRP reinforced concrete slabs under impact load is limited. This study investigated the effect of rebar’s material, amount and arrangement of reinforcements, concrete strength and slab...
Strengthening Reinforced Concrete Deep Beams Using FRP Systems
, M.Sc. Thesis Sharif University of Technology ; Kazemi, Mohammad Taghi (Supervisor)
Abstract
In recent years, the development of the plate bonding repair technique has been shown to be applicable to many existing strengthening problems in the building industry. This technique may be defined as one in which composite sheets or plates of relatively small thickness are bonded with an epoxy adhesive to, in most cases, a concrete structure to improve its structural behaviour and strength. The sheets or plates do not require much space and give a composite action between the adherents. The old structure and the new bonded-on material create a new structural element that has a higher strength and stiffness than original one. According to the available methods of analysis and design for...
A Study on the Effect of Different Lubrication Methods on Surface Integrity and Tool Wear during Ultrasonic-Assisted Milling of CFRP
, M.Sc. Thesis Sharif University of Technology ; Akbari, Javad (Supervisor)
Abstract
The aim of this study was to compare the effect of different cooling conditions (dry, flood, mql) on machined surface parameters (smoothness and protrusion of fibers) and tool erosion in carbon fiber reinforced plastic composite materials (CFRP) in the presence of ultrasonic vibrations or without it. Is. Today, carbon fiber reinforced plastic composite materials or CFRP have become one of the most widely used materials in industry due to their strength and light properties. For example, these materials have been used in the manufacture of products from commercial aircraft to shoes, tennis rackets, golf clubs, fishing rods, etc. The combination of carbon fibers woven with resin in alternating...
Behavior of Concrete Frames Reinforced with FRP Bars
, M.Sc. Thesis Sharif University of Technology ; Khaloo, Alireza (Supervisor)
Abstract
FRP rebars due to various properties such as high resistance to weight ratio, high corrosion resistance, high tensile strength, low weight, resistance to electrical and magnetic conductivity, and other desirable properties, have always been an interesting topic for researchers as an alternative to steel rebars in special conditions.In this research, a two-dimensional sway intermediate concrete frame with three stories and two bays reinforced with GFRP bars was designed and studied. Unlike previous researches and design codes, the compressive strength of the bars was considered in the design process. With computer coding in Matlab software, column interaction diagrams and a special contour...
Fabrication and Investigation of Structure and Mechanical Properties of Bagasse Fibers Reinforced PP: Role of Alkalization and Calcium Carbonate Filler
, M.Sc. Thesis Sharif University of Technology ; Bagheri, Reza (Supervisor)
Abstract
The consumption of plastics in the world is increasing and this is accompanied by the challenges of production from oil products and carbon footprint, waste production and environmental issues. The solutions to these challenges are material recycling and the production of biocompatible plastics. Polypropylene is a widely used polymer that is commonly used in conjunction with reinforcements such as fiberglass. Natural fibers can be substituted to increase the biocompatibility of the composite, which, despite its many advantages, presents challenges. The most important challenge is the poor adhesion of the fibers and the matrix due to the hydrophilicity of natural fibers and hydrophobicity of...
Effect Of Longitudinally Ultrasonic Assisted Milling On Surface Integrity of CFRP Composites
, M.Sc. Thesis Sharif University of Technology ; Akbari, Javad (Supervisor)
Abstract
Nowadays, processes with the ability to machine advanced materials are very much needed by industries. Therefore, compare of a rotary ultrasonic-assisted machining process with a conventional machining process is carried out in this study. In order to evaluate this process, the milling and drilling processes are conducted on the carbon fiber-reinforced polymer composite and titanium materials where cutting forces, surface roughness, and fiber pull-out are selected as critical factors for analysis. As a result, it is seen that rotary ultrasonic-assisted machining has a good performance in the milling and drilling of advanced materials. In particular, it is shown that fiber pull-out is...
Finite element analysis of a CFRP reinforced retaining wall
, Article Geomechanics and Engineering ; Volume 10, Issue 6 , 2016 , Pages 757-774 ; 2005307X (ISSN) ; Toufigh, V ; Desai, C ; Toufigh, V ; Saadatmanesh, H ; Sharif University of Technology
Techno Press
Abstract
Soils are usually weak in tension therefore different materials such as geosynthetics are used to address this inadequacy. Worldwide annual consumption of geosynthetics is close to 1000 million m2, and the value of these materials is probably close to US$1500 million. Since the total cost of the construction is at least four or five times the cost of the geosynthetic itself, the impact of these materials on civil engineering construction is very large indeed. Nevertheless, there are several significant problems associated with geosynthetics, such as creep, low modulus of elasticity, and susceptibility to aggressive environment. Carbon fiber reinforced polymer (CFRP) was introduced over two...
Behavior of polymer concrete beam/pile confined with CFRP sleeves
, Article Mechanics of Advanced Materials and Structures ; Volume 26, Issue 4 , 2019 , Pages 333-340 ; 15376494 (ISSN) ; Toufigh, V ; Saadatmanesh, H ; Ahmari, S ; Kabiri, E ; Sharif University of Technology
Taylor and Francis Inc
2019
Abstract
This research investigates the flexural behavior of a polymer concrete beam/pile encased with carbon fiber sleeve. The mechanical properties of carbon fiber sleeves in tension and cement and polymer concrete in compression were determined. Polymer concrete beams were tested in flexure to determine the bending moment capacity. Then, the test results were compared to the theoretical model results. Finally, a parametric study was conducted to determine the influence of beam/pile parameters on the capacity of the element. Based on the investigation, carbon fiber sleeve filled with polymer concrete exhibits outstanding structural performance including ductility and bending capacity
Environmental effects on the bond at the interface between FRP and wood
, Article European Journal of Wood and Wood Products ; Volume 76, Issue 1 , 2018 , Pages 163-174 ; 00183768 (ISSN) ; Toufigh, V ; Mofid, M ; Sharif University of Technology
Springer Verlag
2018
Abstract
The advantages of fiber reinforced polymer (FRP), such as high specific strength, resistance against corrosion and formability, have made it a more acceptable alternative to conventional materials regarding repairing and retrofitting of structures. Although investigations in recent years have proved the concern of civil engineers about the environmental effects on the bond between FRP and concrete or masonry (especially moisture and temperature), only few researches have been reported on FRP-wood interfaces. This research investigated the effect of five different environments on the bond at the interface between FRP and wood. A series of pull-out tests were performed on 375 wood specimens...
Experimental comparison of cyclic behavior of RC columns strengthened with TRC and FRP
, Article Bulletin of Earthquake Engineering ; Volume 19, Issue 7 , 2021 , Pages 2941-2970 ; 1570761X (ISSN) ; Zargaran, M ; Rahimzadeh Rofooei, F ; Attari, N. K. A ; Sharif University of Technology
Springer Science and Business Media B.V
2021
Abstract
Seven half-scale reinforced concrete (RC) columns with supporting beam were experimentally studied under combined axial and lateral cyclic loading. The specimens were categorized in two groups based on reinforcement ratios. Three specimens were strengthened with carbon fiber reinforced polymer (CFRP) and glass fiber reinforced polymer (GFRP) sheets. Other specimens were strengthened using a high strength mortar reinforced with textile mesh (textile reinforced concrete (TRC)). Strengthening of specimens were carried out using a vertical layer and a horizontal layer of FRP sheet or two vertical and two horizontal layers of textile meshes for TRC specimens. Since the weight of each layer of...
Experimental investigation of square RC column strengthened with near surface mounted GFRP bars subjected to axial and cyclic lateral loads
, Article Scientia Iranica ; Volume 20, Issue 5 , 2013 , Pages 1361-1371 ; 10263098 (ISSN) ; Nicknam, A ; Barkhordari, M. A ; Hosseini, A ; Mehdizad, S ; Sharif University of Technology
Sharif University of Technology
2013
Abstract
This article is intended to highlight the effectiveness of longitudinal Glass Fiber Reinforced Polymer (GFRP) bars in combination with GFRP sheets on the flexural capacity of Reinforced Concrete (RC) columns. Seven half-scale RC columns including five strengthened and two control unstrengthened specimens were experimentally tested under axial and cyclic lateral loads. The strengthened columns with two different longitudinal GFRP bar ratios were tested under three different axial load levels. The flexural strength and ductility parameters of the specimens were calculated by obtaining their deformations and measuring the loads from load cells. The experimental results indicate significant...
Effect of utilizing glass fiber-reinforced polymer on exural strengthening of rc arches
, Article Scientia Iranica ; Volume 26, Issue 4A , 2019 , Pages 2299-2309 ; 10263098 (ISSN) ; Khaloo, A. R ; Shekarchi, M ; Kazemian, A ; Sharif University of Technology
Sharif University of Technology
2019
Abstract
An experimental study of the. flexural behavior of Reinforced-Concrete (RC) arches strengthened with Glass Fiber-Reinforced Polymer (GFRP) layers was performed. A total of 36 specimens including 3 un-strengthenod (control) and 33 strengthened RC arches were tested under centrally concentrated point load. The variables of this study were steel reinforcement ratio, number of GFRP layers, and location and arrangement of GFRP layers. Failure mode, load-displacement response of specimens, crack propagation patterns, and GFRP debonding were examined. The extrados strengthening method was shown to Ix1 more effective than the intrados strengthening one in improving the failure load and rigidity of...
Effect of utilizing glass fiber-reinforced polymer on exural strengthening of rc arches
, Article Scientia Iranica ; Volume 26, Issue 4A , 2019 , Pages 2299-2309 ; 10263098 (ISSN) ; Khaloo, A. R ; Shekarchi, M ; Kazemian, A ; Sharif University of Technology
Sharif University of Technology
2019
Abstract
An experimental study of the. flexural behavior of Reinforced-Concrete (RC) arches strengthened with Glass Fiber-Reinforced Polymer (GFRP) layers was performed. A total of 36 specimens including 3 un-strengthenod (control) and 33 strengthened RC arches were tested under centrally concentrated point load. The variables of this study were steel reinforcement ratio, number of GFRP layers, and location and arrangement of GFRP layers. Failure mode, load-displacement response of specimens, crack propagation patterns, and GFRP debonding were examined. The extrados strengthening method was shown to Ix1 more effective than the intrados strengthening one in improving the failure load and rigidity of...
Strengthening design limitations of an RC frames using FRP column wrapping considering column-to-beam strength ratio
, Article Scientia Iranica ; Volume 14, Issue 5 , 2007 , Pages 405-413 ; 10263098 (ISSN) ; Esmaili, A ; Sharif University of Technology
Sharif University of Technology
2007
Abstract
The aim of this paper is to study the influence of the column-to-beam strength ratio on the seismic strengthening of a column with a Fiber-Reinforced Plastic (FRP) wrapping system. FRP wrapped Reinforced Concrete (RC) columns are analyzed to obtain moment-curvature curves using FRP confined concrete characteristics. A pushover analysis of a 2D model was performed on one and three-story moment-resisting frames, with different column-to-beam strength ratios. The results indicate that FRP strengthening is more efficient in frames with a low ratio of column-to-beam strength, due to the type of lateral failure mechanism of the frame. Also, high values of the column-to-beam strength ratio can be...
Seismic behavior comparison of RC shear walls strengthened using FRP composites and steel elements
, Article Scientia Iranica ; Volume 28, Issue 3 A , 2021 , Pages 1-27 ; 10263098 (ISSN) ; Khaloo, A ; Abdoos, H ; Sharif University of Technology
Sharif University of Technology
2021
Abstract
This paper aims at investigating the seismic behavior of strengthened reinforced concrete (RC) shear walls using a 3D finite element analysis. A series of four different configurations of carbon fiber reinforced polymer (CFRP) composites and four different schemes of steel elements are utilized to compare the two methods of retrofitting RC shear walls with similar dimensions and reinforcement ratios. Nonlinear simulations of the RC shear walls are conducted under the action of lateral cyclic loading in ABAQUS Explicit software. In addition, the numerical modeling for RC walls strengthened by CFRP composites as well as steel elements are validated according to the previous experimental...
Durability of glass-fibre-reinforced polymer composites under seawater and sea-sand concrete coupled with harsh outdoor environments
, Article Advances in Structural Engineering ; 2020 ; Zhao, X. L ; Jafari, A ; Ashrafi, H ; Raman, R. K. S ; Bai, Y ; Khezrzadeh, H ; Sharif University of Technology
SAGE Publications Inc
2020
Abstract
This article presents an investigation on the durability of different glass-fibre-reinforced polymer composites when subjected to harsh outdoor conditions, including freeze/thaw cycles, ultraviolet radiation and moisture, as well as when used with seawater sea-sand concrete for construction applications. To achieve this, the effects of a number of parameters, including the environment of exposure, exposure time, profile cross-sectional configuration and orientation of fibres, on the mechanical properties of different glass-fibre-reinforced polymer composites were studied. To investigate the degradation of the mechanical properties, three-point bending, compression and tension tests were...
Durability of glass-fibre-reinforced polymer composites under seawater and sea-sand concrete coupled with harsh outdoor environments
, Article Advances in Structural Engineering ; Volume 24, Issue 6 , 2021 , Pages 1090-1109 ; 13694332 (ISSN) ; Zhao, X. L ; Jafari, A ; Ashrafi, H ; Raman, RK. S ; Bai, Y ; Khezrzadeh, H ; Sharif University of Technology
SAGE Publications Inc
2021
Abstract
This article presents an investigation on the durability of different glass-fibre-reinforced polymer composites when subjected to harsh outdoor conditions, including freeze/thaw cycles, ultraviolet radiation and moisture, as well as when used with seawater sea-sand concrete for construction applications. To achieve this, the effects of a number of parameters, including the environment of exposure, exposure time, profile cross-sectional configuration and orientation of fibres, on the mechanical properties of different glass-fibre-reinforced polymer composites were studied. To investigate the degradation of the mechanical properties, three-point bending, compression and tension tests were...
Developing a market-oriented approach for supplying flexibility ramping products in a multimicrogrid distribution system
, Article IEEE Transactions on Industrial Informatics ; Volume 17, Issue 10 , 2021 , Pages 6765-6775 ; 15513203 (ISSN) ; Salehi, J ; Moeini Aghtaie, M ; Sharif University of Technology
IEEE Computer Society
2021
Abstract
Rapid growth of the variable and intermittent renewable generation in multimicrogrid distribution network (MMG-DN) has derived a gross violation in power balance due to the scarcity of ramp capacity. To neutralize this shortage, the present study develops a market-oriented approach for supplying flexibility ramping products (FRPs) in an MMG-DN. In this article, the proposed approach appraises a ramping capacity of local microgrids (MGs), which encompass various distributed energy resources through a bilevel programming. To do so, an interval-based security constraint economic dispatch process is accomplished at the upper level considering the network's requirement of upward/downward ramp...
Parametric study of strain rate effects on nanoparticle-reinforced polymer composites
, Article Journal of Nanomaterials ; Volume 2016 , 2016 ; 16874110 (ISSN) ; Haji Gholami, I ; Masajedian, S ; Mertiny, P ; Sameoto, D ; Taheri, F ; Sharif University of Technology
Hindawi Publishing Corporation
2016
Abstract
Crashworthiness, energy absorption capacity, and safety are important factors in the design of lightweight vehicles made of fiber-reinforced polymer composite (FRP) components. The relatively recent emergence of the nanotechnology industry has presented a novel means to augment the mechanical properties of various materials. As a result, recent attempts have contemplated the use of nanoparticles to further improve the resiliency of resins, especially when resins are used for mating FRP components. Therefore, a comprehensive understanding of the response of nanoreinforced polymer composites, subjected to various rates of loading, is of paramount importance for developing reliable structures....