DESIGN AND OPTIMISATION OF HEATED ROAD AND BRIDGE SURFACES

In this research report a description is provided of the state of the art concerning surface heating, and the influence of cable spacing and cover upon heat generation in various carriageway constructions is theoretically investigated. The surface heating system model upon which the trials were based is described, together with its optimisation and the basis of the calculation of the temperature fields and the evaluation processes. A flow diagram is provided to explain the computer program. The calculations were carried out for bituminous carriageway surfaces and concrete roads with and without thermal insulating courses, and in the case of bridge surfaces with plastic material coatings, for different cable spacings (0.5 - 20 cm) and depths (2.0 - 22.5 cm). The results of the numerical calculations are graphically presented. The appendix contains statements on investment and operational costs using electric current from high- and low-voltage networks, as at 25th May 1976. (TRRL)