Dynamic characterization of slab on steel stringer bridges

A parametric study of critical dynamic characteristics of steel stringer highway bridges is presented in this paper. In the modal testing of highway bridges, it is very important to distinguish different mode types and compare the same type of modes between analytical models and experiments. A complete naming system of mode types is developed to aid in sorting all the modes for steel stringer bridges. The naming system is applied to a set Of three dimensional, three span, five girder and four span, five girder bridge models. Basic properties of bridges include length, width and skew. In this paper, the parametric study is done by varying the span ratio of the bridge models. The mode type arrangements are analyzed based on mode shapes, natural frequencies and modal contribution coefficients. Finally, the naming system is applied to the calibration of a nominal bridge model of a representative bridge in Ohio. The study summarized in this paper can be widely used in bridge modeling and analysis.