A Three-Dimensional Pedestrian–Structure Interaction Model for General Applications

A three-dimensional (3D) pedestrian–structure interaction (PSI) system based on the biomechanical bipedal model is presented for general applications. The pedestrian is modeled by a bipedal mobile system with one lump mass and two compliant legs, which comprise damping and spring elements. The continuous gaits of the pedestrian are maintained by a self-driven walking kinetic energy, which is a new driven mechanism for the mobile unit. This self-driven mechanism enables the pedestrian to operate at a varying total energy level, as an important component for further modeling of the crowd-structure dynamic interaction. Numerical studies show that the pedestrian walking on the structure leads to a reduction in the natural frequency, but an increase in the damping ratio of the structure. This model can also reproduce the reaction forces between the feet and structure, similar to those measured in the field. In addition, the proposed model can well describe the 3D pedestrian–structure dynamic interaction. It is recommended for use in further study of more complicated scenarios such as the dynamic interaction between a large scale kinetic crowd and slender footbridge.