Shear strength of welded aluminium plate girders

摘要

Experimental studies of the ultimate shear resistance of welded aluminium alloy plate girders have indicated that at failure, the girders exhibit shear sway characteristics, diagonal buckling of the web and development of plastic hinges within the flanges. Failure generally occurs due to rupture of the heat affected web boundary, during the development of a typical shear failure mechanism. Theoretical procedures for predicting ultimate shear resistance, based on tension-field theory and including material strength reduction factors to allow for welding, are now incorporated in BS8118, Part 1, Structural use of aluminium. However, when compared with available test data, theoretical predictions in accordance with BS8118 appear unduly conservative. Available test results for the ultimate shear resistance of welded aluminium alloy plate girders are reviewed and discussed. An improved theoretical procedure for predicting ultimate shear resistance, similar to that incorporated in BS8118 but retain the rigour of the original tension-field theory, is presented which shows consistent and significantly improved correlation with the test data.