Walking Model to Simulate Interaction Effects between Pedestrians and Lively Structures

Abstract

This paper focuses on evaluating the vertical movements that appear when a pedestrian is walking on a slender platelike structure. For this, the pedestrian is modeled by a dynamic system consisting of a concentrated mass, located in the pedestrian’s center of mass, supported by two springs that simulate the stiffness of the legs. The success of this simple mechanical model is that the resulting contact forces are well adjusted to those observed experimentally for human gait. In this way, the structure is undergoing the moving mass and is loaded with realistic forces, resulting in a proper assembly to study interaction effects. The dynamic response is obtained at any coordinate by the modal superposition method, considering a finite number of modes. Differential equations of the resulting coupled problem are solved using proper numerical techniques (constant time step Runge-Kutta method). Solutions obtained for different scenarios (depending on the dimensions and boundary conditions of the plate and on the mass of the pedestrian with respect to the mass of the floor) are presented and compared with the response of the structure when the pedestrian load is treated as a moving force, as suggested in some design guidelines.