Performance prediction of emulsion treated base layer mixes using indirect tensile strength and resilient modulus test parameters

Emulsion Treated Base layer (ETB) is one of the most emerging base layer stabilization techniques which can effectively reduce the consumption of virgin aggregate in pavement construction industry. ETB mixes exhibit a wide range of strength properties depending on the proportion of its constituents and the method of preparation. Hence, it is essential to predict the performance of ETB from simple test methods such as the resilient modulus test and Indirect Tensile Strength (ITS) test. The study in hand considers ETB with varying emulsion contents, active filler contents, compaction efforts and Reclaimed Asphalt Pavement material (RAP) incorporation, for developing the resilient modulus-ITS relationship. The time lag observed in the resilient modulus test was correlated with the maximum rut depth observed in the wheel tracking test. The rut depths were found to vary between 4 and 11 mm, as the time lags varied from 4 to 18 milli seconds. The resilient modulus of different ETB combinations was found to vary between 1011 and 2950 MPa, as the ITS values varied from 90 to 220 kPa. In the present study, area under the load deformation curve was correlated with the fracture energy and cracking resistance of ETB mixes. Although RAP incorporation in ETB was found to increase the resilient modulus and fracture energy, RAP incorporation possesses serious concerns due to the reduction in the rutting resistance of the resulting ETB mix. The study concluded that ETB with 3-4% emulsion, 1-2% cement (active filler) and compaction effort not less than 50 Marshall Blows can ensure crack and rut resistant mixes.