Faculty of Engineering and the Environment, University of the Witwatersrand, Johannesburg, South Africa; Department of Architecture and Civil Engineering, University of Bath, Bath, BA2 7AY, United Kingdom
Lil, K., Faculty of Engineering and the Environment, University of the Witwatersrand, Johannesburg, South Africa; Darby, A.P., Department of Architecture and Civil Engineering, University of Bath, Bath, BA2 7AY, United Kingdom
This paper presents a simple, practical method of modelling non-destructive impacts macroscopically, where the impact force and post-impact motion of the impacting bodies are of primary concern. The main focus is use of the model for simulating the dynamics of impact dampers used to control the response complex structures. A spring-damper pair is used to model the contact surface between the damper mass and the structure. The key to such a model is the ability to define the contact surface spring stiffness and damping parameters, which does not relate to simple mechanical properties under high-rate loading. A method is developed to derive these parameters by making use of experimentally measured coefficient of restitution and contact time of an impact. The model is able to represent contact force and elastic deformation during an impact process. A simple structure, controlled by an impact damper, is used to compare theoretical and experimental results and demonstrate the validity of the resulting spring-damper model. The results demonstrate that the spring-damper model can be effectively used in situations where the impulse-momentum model fails. © 2008 John Wiley & Sons, Ltd.
Coefficient of restitutions; Contact forces; Contact surfaces; Contact time; Damper models; Damping parameters; High rates; Impact; Impact dampers; Impact forces; Impact process; Impulsive loads; Non-destructive; Passive damping; Practical methods; Response complexes; Simple structures; Spring stiffness; Automobile seats; Dynamics; Mechanical properties; Model structures; Stiffness; Structural dynamics; Damping