Open PRAIRIE: Open Public Research Access Institutional Repository and Information Exchange
Abstract
Common bridge construction practice in South Dakota involves suspending the deck finishing machine and the freshly poured deck overhang from temporary metal brackets. These brackets are attached to the webs of the exterior plate girders. When loaded during construction, the brackets transmit to the web a vertical shearing force plus a couple. Since the webs are not designed for carrying horizontal loads, this type of loading could overstress the webs and appreciably lower their ultimate resistance to buckling. With specifications now permitting large depth to thickness ratios, deflections as well as stresses may be excessive. Rotation of the brackets, caused by deflection of the webs, lowers the paving machine and could result in undesirable thinning of the slab. To reduce stresses and deflections, contractors are now required to place the brackets within six inches of a lateral stiffener. However, because stiffener spacing varies from bridge to bridge, standardization of formwork becomes impossible and the resulting bracket spacing may not always be the most economical. By developing a bracket which could be used without regard to stiffener spacing, construction time and cost could be reduced
