Highway Bridge Impact Studies using A Simple Load Model

This paper suggests a simple load model in which each axle load consists of a constant load plus a sinusoidally varying component. Field tests have been carried out to measure the impact fraction, I, for Six Mile Creek bridge, an 11.28 m span composite steel and concrete girder bridge. The field data have been used to calibrate the simple load model. This model has been used to predict upper bound values of I for bridges of varying span, with this dynamic component set at 4, 6, and 10%. The resulting values are larger than those that have been commonly used, particularly for shorter spans