Mobile impact testing of a simply-supported steel stringer bridge with reference-free measurement

Mobile impact testing of a simply-supported steel stringer bridge is investigated for efficient structural flexibility identification. The classical impact test method requires a number of sensors deployed on the entire structure; in contrast, this paper proposes a novel mobile impact test method that sequentially measures segments of the entire structure with much fewer sensors. The advantage of the proposed approach lies in that it greatly reduces the experimental cost, and it can output the same results of the entire structure's flexibility matrix as the traditional impact test method. In the proposed method, the data processing algorithm is developed to integrate the measurements of all segments for identifying the entire structure's flexibility matrix. Especially, it does not need any transitional nodes to be references by adopting the principle of minimum potential energy, which greatly improves the efficiency of mobile impact testing. Application of the proposed approach to a simply-supported steel stringer bridge successfully verifies its feasibility and efficiency.