The structural life of a road section is one of the aspects to be considered when recommending specific pavement structures. Structural life can be determined by falling weight deflection measurements. If only one single deflection measuring point is available on the road section involved, it is vital to avoid potential error sources. Avoiding error sources is, of course, to be recommended at all times; however, if several measuring points are available on the road section, the errors will be averaged to some degree. The present paper deals with two aspects of processing the results of the falling weight deflection measurements. The first aspect is the premature disruption of an iteration process by curve fitting the various model parameters. Particularly in the case of pavements with bound roadbase such disruption can apparently lead to relatively major over or underestimates of the structural life. The second aspect is the amount of repetitive measurements per measuring point needed to limit the effect upon the calculation of the structural life of the random measuring error using the deflection curve measurement. The effect of the random measuring error can be eliminated by performing a small number of repetitive measurements (about 3 or 4). The paper does not discuss other potential error sources, such as errors in the assumed values for poisson ratio's, and mass inertia effects.
Abstract