Rehabilitation of masonry walls using unobtrusive FRP techniques for enhanced out-of-plane seismic resistance.

摘要

Earthquake damage to unreinforced masonry buildings has shown the vulnerability of perimeter walls to out-of-plane failure. Many of the existing masonry buildings are of historic significance and the damage or collapse of their facades represents a serious cultural loss. The human losses, economic losses in the billion of dollars, and loss of history due to such failures were motivations for this research.; This study was carried out to develop and test innovative FRP rehabilitation techniques that meet the stringent requirements of restoration of historical buildings and to be cost-effective alternatives applicable to existing masonry structures. Unobtrusive FRP rehabilitation techniques that utilize carbon fibre rope impregnated with an epoxy saturant and flexible carbon fibre composite cables, both mounted near the surface of the facade walls in epoxy-filled grooves in the bed and head joints, were developed.; Forty-two wallettes and ten full size walls were constructed of solid clay bricks and were retrofitted by the developed FRP rehabilitation techniques. The effectiveness of the developed techniques was examined under both monotonic loading and quasi-static cyclic loading. The test results demonstrated the high efficiency of the proposed techniques. Significant increases in ultimate capacities, energy absorption and deformability were achieved for various reinforcing schemes compared to the behaviour of the unreinforced specimens. In order to analyze performance, extend the range of the investigated parameters and define limitations, a rigid body analytical model was developed to predict the post-cracking lateral pressure-displacement response of the FRP-reinforced walls under biaxial bending.; The implementation of these techniques could have a significant economic impact in addition to the cultural and social impacts of conservation of the architectural heritage. Since the developed techniques are applicable to existing masonry buildings in general, it is anticipated that they will contribute to the Canadian economy through upgrading existing masonry buildings and extending their service life.