• The International Concrete Abstracts Portal is an ACI led collaboration with leading technical organizations from within the international concrete industry and offers the most comprehensive collection of published concrete abstracts.

International Concrete Abstracts Portal


Title: Investigation of CFRP Torsional Strengthening of RC Beams using DIC Photogrammetry

Author(s): Ghaidak Al-Bayati, Riadh Al-Mahaidi and Robin Kalfat

Publication: Symposium Paper

Volume: 327


Appears on pages(s): 47.1-47.20

Keywords: Photogrammetry, torsion, crack width, CFRP laminates, NSM, concrete beam, epoxy, morta

DOI: 10.14359/51713368

Date: 11/1/2018

In recent research, the use of the near-surface mounted (NSM) technique has been proven to increase the torsional strength of reinforced concrete (RC) members. In this paper, an investigation into the torsional deformation characteristics of the ten RC beams strengthened using the NSM technique is reported and evaluated using photogrammetry. The experimental results of two control beams and eight beams strengthened using CFRP laminate embedded into pre-cut grooves using epoxy and mortar are evaluated. The Digital Image Correlation Photogrammetry (DIC) is used to determine the three-dimensional displacement of targets placed on the north and south faces of the beams at selected load levels up to failure. The main aim of this study was to measure the propagation of torsional crack width with increasing torque for each beam. The torsional deformations of the beams are evaluated and verified with the photogrammetry measurements and the differences in the width of the large torsional cracks across the tested beams are highlighted and compared. The width of the torsional cracks for the strengthened beams was smaller than that that of the control beams at the same load level. Similar deformation mechanisms were observed for the strengthened and control beams.