Techno Press
Techno Press

Steel and Composite Structures   Volume 29, Number 2, October25 2018, pages 187-200
DOI: http://dx.doi.org/10.12989/scs.2018.29.2.187
 
Experimental and FE investigation of repairing deficient square CFST beams using FRP
Suzan A.A. Mustafa

 
Abstract     [Full Text]
    This paper handles the repairing of deficient square Concrete-Filled Steel-Tube (CFST) beams subject to bending through an experimental and numerical program. Eight square-CFST beams were tested. A 5-mm artificial notch was induced at mid-span of seven beams, four of them were repaired by using CFRP sheets and two were repaired by using GFRP sheets. The beam deflection, strain and ultimate moments were recorded. It was found that providing different cut-off points for the different layers of FRP sheets prohibited failure at termination points due to stress concentrations. Using different lengths of FRP sheets around the notch retarded crack propagation and prevented FRP rupture at the crack position. Finite element analysis was then conducted and the proposed FE model was verified against the recorded experimental data. The influence of various parameters as FRP sheet length, tensile modulus and the number of layers were studied. The moment capacity of damaged square-CFST beams was improved up to 77.6% when repaired by using four layers of CFRP, however, this caused a dramatic decrease in beam deflection. U-wrapping of notched-CFST beam with 0.75 of its length provided a comparable behaviour as wrapping the full length of the beam.
 
Key Words
    CFST; deficient; damaged; composite; FRP; beam; experimental; finite element
 
Address
Department of Structural Engineering, Faculty of Engineering, Zagazig University, Egypt.
 

Techno-Press: Publishers of international journals and conference proceedings.       Copyright © 2019 Techno Press
P.O. Box 33, Yuseong, Daejeon 305-600 Korea, Tel: +82-42-828-7996, Fax : +82-42-828-7997, Email: technop@chol.com