Design and construction of continuously reinforced concrete composite pavement for the A63 South Docks Road Hull

The paper describes the approach adopted for the design and construction of a continuously reinforced concrete road base (CRCB) pavement for a major trunk road proect in the north-east region of the United Kingdom. The trunk road, known as the South Docks Road, is currently under construction and programmed for completion in Autumn 1985. Continuously reinforced concrete construction has been used extensively in Belgium and the United States. However, because there is little experience of the use of CRCB in Britain it is regarded as a "special" form of pavement construction. South Docks Road will carry a large volume of heavy commercial traffic to and from the commercial port, docks and city centre of Kingston-Upon-Hull. The mainline pavement has been designed to carry a loading in excess of 200 million standard axles and comprises 100 mm bituminous surfacing material overlaying a 240- mm-thick, continuously reinforced concrete slab. The CRCB for the complete 8 km dual 2-lane carriageway was completed within a period of 29 days utilising prefabricated mats of reinforcement laid within a continuous two stage operation. The average length of 8.225-m-wide carriageway slab laid in one day varied between 600 - 700 m; the maximum achieved was 858 m. The new road is constructed on the northern foreshore of the river Humber and traverses poor ground conditions, consisting glacial deposits overlain by alluvium and two areas of made ground from refuse tips. The paper briefly discusses the appropriateness of composite CRCB construction in condition of poor subsoils and high axle loading. Design modification introduced by the Consultant concerning the continuity, content and placement of reinforcement and the requirement for longitudinal joints are discussed. Construction problems associated with edge detailing of composite pavements in the rural and urban environments are reviewed. Reference is made to the design methodology, and factors affecting the performance of continuously reinforced concrete pavements examined. Construction is described identifying paving methods and techniques employed, plant and equipment, materials and quality control. Aspects of critical construction planning and the design/construction economics of CRCB are discussed Land areas where future research could usefully be concentrated are briefly outlined.