ABSTRACT
The new Ceres Dam is unique in Southern Africa in having an asphaltic concrete core.
This is particularly appropriate for the site since the core provides the required flexibility to sustain Maximum Credible Earthquakes of magnitude 7.0 and high differential settlements due to variable founding conditions. In addition the asphalt core is cost-effective because of local unavailability of clay materials and because it allowed all-weather construction.
The asphaltic concrete design is similar to that for road pavements but the emphasis is on minimum permeability – achieved by dense mixes (<2% air voids), and maximum flexibility-achieved by using bitumen contents of about 7%.
Rigorous monitoring of the computer controlled batch plant ensured that the mix produced as correct. Hence the core laying proceeded according to specification and within a tight schedule.
