Abstract
This paper addresses the design of stainless steel sections with large circular openings subject to shear and bending. A total of nine tests on pairs of C sections using 2 and 3 mm thick stainless steel in austenitic 1.4301 and lean duplex 1.4162 grades was performed. The tests showed that the shear resistance at an opening is controlled by local compression at a radial cross-section at approximately 25° to the vertical. For closely spaced openings, the angle of highest stress increases to about 65° to the vertical. The shear resistance of a Class 4 web is also affected by local buckling around the opening, which is a function of its diameter to steel thickness ratio. An equilibrium model is presented which predicts the normal stress on the radial planes around an opening. A simplified formula for the local buckling strength around circular web openings is also presented, which agrees well with the test results.