CFRP Laminates Reinforcing Performance of Short-Span Wedge-Blocks Segmental Beams

Two of the main advantages of segmental construction are economics, as well as the rapid construction technique. One of the forms of segmental construction, for structural elements, is the segmental beams that built-in short sections, which referred to segments. This research aims to exhibit a new technique for the fabrication of short-span segmental beams from wedge-shaped concrete segments and carbon fiber reinforced polymers (CFRP) in laminate form. The experimental campaign included eight short-span segmental beams. In this study, two selected parameters were considered. These parameters are; the number of layers of CFRP laminates and the adhesive material that used to bond segments to each other, forming short-span segmental beams. The test results showed that for segmental beams reinforced by 2-layer of CFRP laminates, undergoes less deflection and sustained considerable ultimate loading value of 38.4%–104% than beams reinforced by 1-layer. Moreover, the test of segmental beams fabricated by adhering to the concrete segments with epoxy resin exhibited an increase in ultimate loading by 16%–65% than beams constructed using cementitious adhesive for bonding the wedge-shaped segments. Theoretically, segmental beams were analyzed by the American Concrete Institute (ACI) 440.2R-17 procedure with slight modifications. The analysis gave an overestimation of flexural strength for segmental beams when compared with experimental outcomes.

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Evaluation of Wedge-Block Concrete Beams Reinforced with EBR-CFRP Laminates by Modified ACI 440.2R-2017 Guide

10.20944/preprints201906.0097.v1 ◽

2019 ◽

Author(s):

Ali Abdulhameed ◽

AbdulMuttalib Said

Keyword(s):

Concrete Beams ◽

American Concrete Institute ◽

Cementitious Materials ◽

Fiber Reinforced Polymers ◽

Small Scale ◽

Carbon Fiber Reinforced Polymers ◽

Reinforced Polymers ◽

Cfrp Laminates ◽

A New Technique ◽

Two Parameters

Concrete beams built from individual segments connected to each other by special mechanism referred as segmental beam. The aim of this research is to exhibit a new technique for fabrication of small scale segmental beams from wedge shape unreinforced concrete segments and pultruded carbon fiber reinforced polymers (CFRP) in laminate form. Eight segmental beams including two parameters are tested experimentally. The first parameter is the area of CFRP and second is the adhesive material used to bond segments of the beams. The test shows that segmental beams have a higher ratio of CFRP area undergoes less deflection and sustain higher ultimate loading value of 38.4%. Moreover, the test of beams with concrete segments adhered by epoxy resin sustain a higher load than segments adhered by cementitious materials about 11.87%. Theoretically, segmental beams were analyzed by modified American Concrete Institute ACI 440.2R-17 report with slight modifications. The analysis results in an overestimation of flexural strength of segmental beams when compared with experimental outcomes.

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Bond between Concrete and Multi-Directional CFRP Laminates

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.133-134.917 ◽

2010 ◽

Vol 133-134 ◽

pp. 917-922 ◽

Cited By ~ 2

Author(s):

José Sena-Cruz ◽

Joaquim Barros ◽

Mário Coelho

Keyword(s):

Carbon Fiber ◽

Civil Engineering ◽

Fiber Reinforced Polymers ◽

Structural Elements ◽

Engineering Applications ◽

Carbon Fiber Reinforced Polymers ◽

Reinforced Polymers ◽

Cfrp Laminate ◽

Cfrp Laminates ◽

Pullout Tests

Recently, laminates of multi-directional carbon fiber reinforced polymers (MDL-CFRP) have been developed for Civil Engineering applications. A MDL-CFRP laminate has fibers in distinct directions that can be arranged in order to optimize stiffness and/or strength requisites. These laminates can be conceived in order to be fixed to structural elements with anchors, resulting high effective strengthening systems. To evaluate the strengthening potentialities of this type of laminates, pullout tests were carried out. The influence of the number of anchors, their geometric location and the applied pre-stress are analyzed. The present work describes the carried-out tests and presents and analyzes the most significant obtained results.

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Experimental Study of a New Strengthening Technique of RC Beams Using Prestressed NSM CFRP Bars

Sustainability ◽

10.3390/su11051374 ◽

2019 ◽

Vol 11 (5) ◽

pp. 1374 ◽

Cited By ~ 1

Author(s):

Vicente Alcaraz Carrillo de Albornoz ◽

Eva García del Toro ◽

M. Isabel Más-López ◽

Alfredo Luizaga Patiño

Keyword(s):

High Performance ◽

Fiber Reinforced Polymers ◽

Carbon Fiber Reinforced Polymers ◽

Reinforced Polymers ◽

Near Surface ◽

Environmentally Sustainable ◽

Sustainable Solutions ◽

Reinforced Beams ◽

A New Technique ◽

Strengthening Technique

The reinforcement of structural elements subjected to bending with carbon fiber reinforced polymers (CFRP) located on the underside of the element to be reinforced (known as near surface mounted or NSM) is an effective technique that provides environmentally sustainable solutions in the field of civil engineering. Introducing preloads on the reinforcing elements allows us to maximize the high performance of CFRPs, besides recovering deformations. A new technique to perform the pre-stressing of CFRP bars in NSM configuration is described in this paper. The technique introduces the preload on the rods after they have been placed in the grooves, and with a system that acts and reacts against the beam itself. We also present the results of a testing campaign conducted to determine the effectiveness of said technique. Breakage of the control beams (without reinforcement) was ductile, while breakage of reinforced beams was explosive. Pre-stressing the reinforcing elements allowed us to increase the bearing capacity of the beams 170% compared to the control beams, also resulting in an increase in the rigidity of the reinforced elements and a decreased cracking of the beam. The results however are only slightly better than those of a conventional CFRP NSM reinforcement, due to the appearance of cavities in the groove where the adhesive didn’t manage to penetrate.

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A Study of Cutting Force and Force Coefficients in Orthogonal Cutting of High-Strength CFRP T700 Laminates

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.693.704 ◽

2016 ◽

Vol 693 ◽

pp. 704-709

Author(s):

Kun Xian Qiu ◽

Ya Xing Bie ◽

Sheng Qin ◽

Qing Long An ◽

Ming Chen

Keyword(s):

Cutting Force ◽

Orthogonal Cutting ◽

Cutting Tools ◽

High Strength ◽

Fiber Reinforced Polymers ◽

Force Model ◽

Carbon Fiber Reinforced Polymers ◽

Reinforced Polymers ◽

Cfrp Laminates ◽

Force Coefficients

High strength carbon fiber reinforced polymers (CFRP) with unidirectional laminate structure have gradually developed into major materials in load-bearing aerospace components, and the cutting demand of CFRP is increasing. In this work, orthogonal cutting tests were conducted on T700 high-strength CFRP laminates to get the mechanistic force model of special cutting tools. Also cutting force coefficients were obtained when cutting T700 high-strength CFRP laminates under different fiber orientations. Experimental results showed that the lowest cutting force was obtained when fiber orientation was between 120° and 150°.

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