Biodynamic modelling of human rhythmic activities

Abstract

Excessive vibration problems related to building floors concerning the human comfort have been reported by several researchers in the past two decades. The reason for those vibrations is mainly related with the current trend for the design of slender and flexible structural systems, with the inherent low damping. Consequently, such floors are prone to resonant motion which may reach high vibration levels once their natural frequencies lie in the same range of the human induced forces. In this sense, the human activities, such as walking, jumping or bouncing have been described in some design guides by pure forces acting on the structure. This assumption has conducted to a more or less conservative structural design depending on the chosen loading model function. Recent studies have demonstrated that the use of biodynamics models in order to represent the human behaviour may lead to a more realistic, reasonable and economical design, as they take into account the human body dynamic properties. This paper aims at evaluating the body dynamic parameters by means of a force plate and an accelerometer mounted on the human body when a rhythmic activity (jumping) is developed. This way, experimental tests are carried out both on a rigid surface and on a vibrating floor so that the mass, spring and damping of the identified human biodynamic model can be obtained through an optimisation method.