Analytical and Experimental Behavior of a Novel Anchorage Layout for FRP Confined Rectangular Columns

In the last two decades, FRP systems have been largely used to improve the performance of structural members, due to their high strength to weight ratio and corrosion resistance. Application of this strengthening procedure in circular columns has resulted quite beneficial in increasing their seismic and axial capacity. Whereas in the rectangular ones, strength enhancement was considerably less. Hence this paper aims in introducing the FRP strengthening mechanism of rectangular columns and highlighting its limitations in strength enhancement when compared to the circular counterparts. The corner radii, aspect ratio and concrete compressive strength effect on the capacity increase rate are evaluated as well, based on the results of the large database provided by different experimental studies performed until now. A novel anchorage configuration is suggested to overcome the existing limitations for enhancement of axial strength in this column category. Analysis of the improvement that this solution provides to the confinement pressure distribution was performed by ANSYS Software. Experimental and analytical results supported the increase of stress distribution uniformity in the anchored rectangular column section.

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