experimental overlays using rolled asphalt and asphaltic concrete a1, stilton (1970)

an experiment to strengthen the northbound carriageway of trunk road a1 near stilton, huntingdonshire, is described. four experimental overlays 50 mm thick were laid on both lanes; three were of rolled asphalt with differing binders and the fourth was of asphaltic concrete that was subsequently surface dressed. the binders used in the rolled asphalts were 50 pen pitch-bitumen (control) a 50 pen bitumen with a high penetration index and a 35 pen bitumen. the structural performance, the resistance to skidding, and the resistance to deformation are being studied. (a)