Strengthening of Reinforced Concrete Bridge Columns with FRP, Using Wrapping, Near-surface Mounted and Combined Methods

Bridges are considered as part of the infrastructure of each country, which dedicate themselves a large part of the cost of road construction. Due to their structural elegancy, bridges have high degree of vulnerability to natural disasters such as earthquake, especially bridge columns that carry loads from deck to foundation. So, precise and safe design of bridge components, especially columns, should be considered. The earthquakes which have occurred in the United States, Japan, Taiwan, and Turkey in the 1990s, have caused significant damages to bridges. Bridges require column retrofit due to reasons such as increased loads because of increased traffic, service to vehicles heavier than initial loads, low quality of implementation, seismic issues, environmental issues such as corrosion of reinforcement, pre-stressed losses due to concrete creep and wrapping, change of codes and short column effect in sloping bridges made due to bases with variable height. One of the significant damages in bridge columns depends on shear failure due to the short column effect and inadequate shear capacity of the bridge columns. In this paper, using finite element method, new and combined methods of bridge strengthening with FRP are considered. For this purpose, a short column which was weak in shear, has been modeled and retrofitted by different methods such as wrapping, NSM, and combination methods, and has been analyzed by finite element method. Results showed that the combination method is the best method for retrofitting of short columns bridges.