Ductile Concrete Material with Self-Healing Capacity for Jointless Concrete Pavement Use

The existence of joints in concrete pavement tends to cause many distresses and driving discomfort, thus resulting in high maintenance and shortened service life. This study achieved jointless function in concrete pavement by utilizing the high ductility and self-healing capacity of engineered cementitious composite (ECC). From the preliminary experimental results, ECC showed high strain capacity of 4.4% and deflection capacity of 7.9 mm under tension and bending, overcoming the brittleness of normal concrete. The flexural and compressive strengths of ECC are 12.2 and 45.8 MPa, respectively, which could meet the requirements of heavy-duty concrete pavement in accordance with design guidance in China. Under restrained shrinkage, ECC also shows a very low tendency to form fracture failure. In addition, the self-healing phenomenon is observed in ECC. Its stiffness, tensile strain capacity, tensile strength, and resonant frequency value show a very high recovery level after self-healing, nearly approaching that of virgin ECC of the same age. The water permeability coefficient of predamaged ECC decreases gradually with self-healing age, and eventually is close to that of the undamaged specimens. Based on the experimental results, it is concluded that ECC material, as expected, has the potential to be used in jointless concrete pavement.