Search

Results of the behavior of pultruded fiber-reinforced polymer (FRP) I-shaped beams subjected to concentrated loads in the plane of the web are presented. Twenty beams with nominal depths from 152.4 to 304.8 mm were tested in three-point bending with a span-to-depth ratio of four. Load was applied to the top flange directly above the web—12 without bearing plates and 8 with bearing plates of varying width and thickness. All test specimens failed with a wedgelike shear failure at the upper web-flange junction. Finite-element results support experimental findings from strain gauge and digital image correlation data. Bearing plates increased beam capacity by 35% or more as a function of bearing plate width and thickness. Bearing plates increased average shear stress in the web at failure from 17.4 to 27.2 MPa—below the accepted value of in-plane shear strength (69 MPa). A design equation is presented, and predicted capacities are compared with experimental results. The average value of experimental capacity t...

Five 609.5-mm deep fiber-reinforced polymer (FRP) beams with a span-to-depth ratio of 4∶1 were tested in three-point bending with the beam ends constrained to prevent global failure. A concentrated load was applied at midspan either directly to the top flange or through a 101.6 mm wide by 12.7-mm thick FRP bearing plate resting on the top flange. VIC-3D Digital Image Correlation Measurement Software from Correlated Solutions captured out-of-plane displacement of the webs, and Southwell plots were generated to determine buckling loads. Each specimen experienced a stability failure of the web before undergoing material failure in the upper web-flange junction. On average, web buckling occurred at 90% of the ultimate load. The introduction of a bearing plate did not significantly affect the buckling load or ultimate capacity of the specimens. One specimen was tested into the postbuckling range, unloaded, and reloaded to material failure and experienced no loss of strength or stiffness. Another specim...