THE PERFORMANCE OF JOINTED CONCRETE PAVEMENTS AS AFFECTED BY FACTORS OTHER THAN TRAFFIC INDUCED STRESS

Abstract

Design and construction techniques as developed overseas have been used in Southern Africa on Portland cement concrete pavements with little variation based on local experience, This paper describes methodology by which Portland cement jointed unreinfored pavements are being evaluated with the aim of improving local design and contruction techniques. Indications are that failures found on the pavements can primarily be attributed to inadequate construction techniques and control. Although the pavements are performing very well (only 11 % of the road system have cracked outside the joints) it is felt that an improvement in performance is possible if subgrades are compacted properly to reduce settlement, non erodible subbases are constructed, load transfer at joints are enhanced by using low shrinking concrete, joints are kept properly sealed and Portland cement paved shoulders are used.