Compressive Stresses in Concrete Pavements and Related Maintenance Problems

The M20 motorway between Junctions 3 and 5 near Maidstone (UK) is an unreinforced pavement with joint spacings of 5m and 6m, comprising warping joints with contraction joints every 30m. The pavement was constructed at the beginning of the 1 970s. A contract for maintenance between Junctions 4 and 5 in 1991 was plagued by problems. Saw-cutting operations for full depth repairs released substantial compressive stresses, with significant movement of the pavement slabs. Nevertheless some newly constructed bays suffered from transverse tension cracking, to the extent that load transfer was compromised, requiring the bays to be reconstructed.