Abstract
Empirical studies of traffic flow variations and theoretical analyses have been conducted in order to derive characteristics of traffic flow variability, particularly in relation to peak periods. The length of flow counting interval, tr, as well as profiles of flow rate variations for peak periods have been determined. The flow profiles are based on a time scale divided into units tr, within which demand flow is assumed as stationary. A computer simulation program .has been developed' for modelling of traffic flow with varying flow rates accordingly to an assumed curve.