Experimental studies on perforated plate girders with inclined stiffeners

Ultimate load behaviour of perforated steel plate girders with inclined stiffeners is presented in this paper. A series of experimental tests on ten simply supported girders were tested to failure under shear load applied at the centre of gravity of the section. Centrally located circular web openings of various diameters were introduced at the middle panels of the girders. Effects of different inclination angles of intermediate stiffeners on the post-buckling behaviour are the main focus of the present study. Five different angles, viz., 90°, 75°, 60°, 45° and 30°, measured from the bottom flange, were accounted for in the tests. Considerable variations of strength, failure characteristic, and load-deflection response may be observed due to effects of such inclinations. Test results show significant increases in the ultimate strength to the extent of 92% as the angle of inclined stiffeners reduced. Non-linear finite element analyses were also carried out to provide additional support for the test results. A reasonably close agreement between the two sets of results establishes the accuracy of the numerical analysis.