The paper provides a model of continuous walking load in the vertical
direction based on the available measured force-time histories
induced by a single foot of an individual walking. The characteristics
and models of people walking are examined and all the parameters
defining the load model, including walking velocity and frequency,
Fourier coefficients and phase lags, are investigated. The velocity and
frequency of people walking are determined from site survey and the
relation between walking velocity and frequency are introduced. The
available measured force-time histories of four types of walking
(normal, brisk, slow and fast) are digitised and expressed by
polynomials. The forces produced by two adjacent foot steps are
combined based on the principle that the integration of walking force
in a period is equal to the product of the period and the weight of the
walker. Fourier integration is used to determine the first six Fourier
coefficients and phase lags. The load models of the four types
walking are assessed. It is concluded that the normal walking of the
four types of walking is suitable for the use in design and analysis. |