Experimental Study of Stress and Deformation of Reclaimed Asphalt Concrete at Different Temperatures

Asphalt concrete has been used as a material for dam core walls because of its impermeability, durability and reliability. Firstly, asphalt is a temperature-sensitive material, and many of its characteristics are related to temperature. Secondly, because of the increasing construction height of the dam, the pressure on the asphalt concrete core wall is also great. Finally, for the purpose of resource utilization, it is necessary to verify whether the reclaimed asphalt concrete can be used in dam construction. Therefore, it is necessary to study the stress and deformation characteristics of recycled asphalt concrete under different temperatures and confining pressures. In this study, three groups of triaxial tests of reclaimed asphalt concrete were carried out for the first time in a new temperature-controlled room. Duncan Zhang's E-v model was used to fit the test results. The results show that the stress-strain curves of reclaimed asphalt concrete show softening characteristics at low temperatures and low confining pressure. It evolves to a hardening type with the increase in temperature and confining pressure. The bulk curve is first contracts but is followed by dilatancy. The dilatancy characteristics become more obvious at low temperatures and low confining pressure. With the increase in temperature and confining pressure, the dilatancy characteristics will weaken. Duncan Zhang's E-v model has a good fitting effect on the stress-strain relationship but a poor fitting effect on the volumetric curve. The research of this paper can better combine the utilization of waste resources with engineering and achieve the aim of resource-saving and waste utilization under the premise of ensuring the safety of the engineering.