THE HEAVY VEHICLE SIMULATOR TEST ON FREEWAY P157 (1 AND 2) BETWEEN PRETORIA AND JAN SMUTS AIRPORT

A heavy vehicle simulator test was performed on freeway P157/(1 and 2) near Olifantsfontein, between Pretoria and Jan Smuts airport. The pavement structure consists of a relatively thin surface layer, a crushed-stone base and a stabilized subbase. The behaviour of the pavement was monitored and analysed by means of a mechanistic analysis. The pavement performed very well but deteriorated when water was sprayed onto the surface. The behaviour and mechanistic analysis indicated that the equivalency coefficient is dependent on a range of factors such as the pavement layer, wheel load, number of repetitions and environmental conditions. Untreated crushed-stone base pavements can be expected to carry traffic well into the E4 traffic class (12 to 50 million E80s) in the moderate climates of the country. For this purpose good drainage and timely maintenance of the surface layer are required. For freeway P157/(1 and 2) it is recommended that a surface treatment or a thin premix overlay should be applied within the next two to three years. (Author)