Determination of cementitious grouts for semi-rigid pavements

With the increasing traffic flow and traffic loads, the traditional asphalt pavement and concrete pavement cannot satisfy the pavement requirement in the long term. Therefore, researchers have been looking for new techniques and methods to develop durable and cost-effective pavement structures. The semi-rigid pavement is a composite pavement that is composed of a porous asphalt mixture with air voids between 25-30% and cementitious grout with high fluidity. This laboratory investigation aims at developing cementitious grout as well as evaluating its contribution in the resultant semi-rigid pavement. In the first phase of this research, different cementitious grout mixtures prepared with the maximum particle size of 0.6mm sand, cement, two types of superplasticizer and two water-cement ratios. Four laboratory tests, including fluidity test, compressive strength test, flexural strength test and drying shrinkage test, were adopted to evaluate the workability and mechanical properties of cementitious grouts. According to these properties, the most suitable mixture is proposed for semi-rigid pavement. In the second phase, the performance of semi-rigid pavement is investigated by applying the proposed cementitious grout to 65 mm porous asphalt specimens. The research concludes that the grout mixture proportion proposed in this study, has good grouting ability and the semi-rigid pavement have superior performances.