A framework for experimental determination of localised vertical pedestrian forces on full-scale structures using wireless attitude and heading reference systems. (18th August 2016)

• Record Type: Journal Article
• Authors: Bocian, M.; Brownjohn, J.M.W.; Racic, V.; Hester, D.; Quattrone, A.; Monnickendam, R.
• Is Part Of: Journal of sound and vibration. Volume 376(2016)
• Page Start: 217
• Page End: 243
• Publication Date: 2016-08-18
• Subjects: Loading from walking pedestrians -- Force location tracking -- Human–structure interaction -- Wireless sensor network -- Vibration serviceability of structures -- Pedestrian dead reckoning; Sound -- Periodicals; Vibration -- Periodicals; Son -- Périodiques; Vibration -- Périodiques; Sound; Vibration; Periodicals; Electronic journals; 620.205
• DOI: 10.1016/j.jsv.2016.05.010
• Languages: English
• ISSNs: 0022-460X

Abstract

Abstract: A major weakness among loading models for pedestrians walking on flexible structures proposed in recent years is the various uncorroborated assumptions made in their development. This applies to spatio-temporal characteristics of pedestrian loading and the nature of multi-object interactions. To alleviate this problem, a framework for the determination of localised pedestrian forces on full-scale structures is presented using a wireless attitude and heading reference systems (AHRS). An AHRS comprises a triad of tri-axial accelerometers, gyroscopes and magnetometers managed by a dedicated data processing unit, allowing motion in three-dimensional space to be reconstructed. A pedestrian loading model based on a single point inertial measurement from an AHRS is derived and shown to perform well against benchmark data collected on an instrumented treadmill. Unlike other models, the current model does not take any predefined form nor does it require any extrapolations as to the timing and amplitude of pedestrian loading. In order to assess correctly the influence of the moving pedestrian on behaviour of a structure, an algorithm for tracking the point of application of pedestrian force is developed based on data from a single AHRS attached to a foot. A set of controlled walking tests with a single pedestrian is conducted on a real footbridge for validation purposes. A remarkably good match between the measured and simulated bridge response is found, indeed confirming applicability of the proposed framework. Highlights: A framework for experimental studies on crowd–structure system is proposed. Wireless network of smart motion monitors is used. Vertical force from walking pedestrian and structural response are captured in situ. Single 3D motion monitor can be used to reconstruct pedestrian vertical force. Single 3D motion monitor can be used to get point of application of that force.