INTERACTION EFFECTS OF BENDING AND TROSION ON STEEL BOX GIRDERS

The purpose of this study is to investigate the ultimate strength behavior of box girders when subjected to simultaneously applied bending and torsional loads. The study was conducted by experimentally testing several straight box girder models. Both non-composite and composite girders were tested. The results were compared to expected behavior based on available analytical methods. From the test results a non-dimensional interaction curve was developed to expedite the load factor design of box girders. Simple relationships are also presented to relate straight box girders to curved box girders. With these relationships, the interaction curves can be applied to curved box girder designs. Application of these relationships are given by a design example. /FHWA/