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
Appears on pages(s): 47.1-47.20
Keywords: Photogrammetry, torsion, crack width, CFRP laminates, NSM, concrete beam, epoxy, morta
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.