Investigation into the early trafficking of emulsion treated (ETB) foamed bitumen (FB) bases treated in combination with cement and cement (OPC) only

Abstract

The South African Road Agency Limited (SANRAL Northern Region) requested that more information be generated to determine the early trafficking potential of ETB, FB and Cement stabilized materials, in order to determine when the traffic could safely be placed on the recycled layer. The ETB and FB treatments are usually done in combination with cement. The dynamic mechanical triaxial test (K-Mould test) was used to evaluate the maturity of all three stabilized materials in the laboratory after different curing periods. To compare the different treatment methods the results were converted into predicted life expectancy of 80 kN axle loads required to cause a surface rut of 10 mm in the 200 mm stabilized layer. What the results showed was that the greatest contribution to the final strength came from the cement. This result was later confirmed by independent tests done on another project comparing the contributions of the stabilization agents towards the ITS of the stabilized material