Doped With Fly Ash High-performance Pavement Concrete Durability

Pavement high performance concrete (PHPC) is new high-tech concrete designed meticulously for pavement, which adopt ordinary concrete raw materials and take durability performance as design object, is favorable to the environmental protection and sustainable development of highway construction, and have extensive development prospects.The paper presents the demand of raw material used in PHPC firstly, then proposes the mixture ratio design method of PHPC mixing fly ash on the basis of orthogonal design theory, and studied the workability, air content, tensile and compression strength by the means of orthogonal experiment, analyzes the influence of fly ash to the workability, air content, tensile and compression strength. On the other hand, the paper also studied durability about pavement, including frost resistance, anti-permeability, shrinking performance, wear-resisting performance, fatigue property etc, and analyzes the influence of fly ash to the pavement performance. The optimum design is decided by the means of the mixture ratio design. As a result of durability evaluation, the concrete of the optimum design has excellent durability.In order to study PHPC further, fly ash—cement mortar and interface structure of PHPC are tested by using Micro structural analysis technology such as mercury intrusion porosimetry and SEM. And mechanism about fly ash to improve PHPC performance is also discussed.