Retrofitting of squat masonry walls by FRP grids bonded by cement-based mortar

  • Popa, Viorel (Department of Reinforced Concrete Structures, Technical University of Civil Engineering of Bucharest) ;
  • Pascu, Radu (Department of Reinforced Concrete Structures, Technical University of Civil Engineering of Bucharest) ;
  • Papurcu, Andrei (Department of Reinforced Concrete Structures, Technical University of Civil Engineering of Bucharest) ;
  • Albota, Emil (Department of Structural Mechanics, Technical University of Civil Engineering of Bucharest)
  • Received : 2014.11.10
  • Accepted : 2015.11.02
  • Published : 2016.01.25


For seismic retrofitting of masonry walls, the use of fibre reinforced cement-based mortar for bonding the fibre grids can eliminate some of the shortcomings related to the use of resin as bonding material. The results of an experimental testing program on masonry walls retrofitted with fibre reinforced mortar and fibre grids are presented in this paper. Seven squat masonry walls were tested under unidirectional lateral displacement reversals and constant axial load. Steel anchors were used to increase the effectiveness of the bond between the fibre grids and the masonry walls. Application of fibre grids on both lateral faces of the walls effectively improved the hysteretic behaviour and specimens could be loaded until slip occurred in the horizontal joint between the masonry and the bottom concrete stub. Application of the fibre grids on a single face did not effectively improve the hysteretic behaviour. Retrofitting with fibre reinforced mortar only prevented the early damage but did not effectively increase deformation capacity. When the boundaries of the cross sections were not properly confined, midplane splitting of the masonry walls occurred. Steel anchors embedded in the walls in the corners area effectively prevented this type of failure.


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