Research On Self-healing Technology Of Dense Asphalt Concrete By Induction Heating

Asphalt concrete pavement under the action of long-term vehicle load and the external environment, there will be different types of diseases, road performance will be reduced in different degrees, at the same time reducing the service life of asphalt road. Polymer materials such as waterproofing agent and asphalt regenerant was applied to the maintenance and repair of the asphalt pavement, these materials will be different degree influence on the performance of the pavement and the use of the maintenance fee, etc. Utilizing the healing ability of asphalt binder crack itself exists,and temperature sensitivity of asphalt binder, electromagnetic induction heating technology was applied to the repair of asphalt surface, through the electromagnetic induction heating asphalt concrete mixed conductive materials to improve its crack healing properties is advanced technology among the repair methods of asphalt pavement at present stage.This article is researched through the AC-13 C asphalt concrete mixed with conductive material- steel wool, on the basis of the composition design, mixing process and mechanical properties of asphalt concrete mixed with steel wool,electromagnetic induction heating asphalt concrete mixed with steel wool to study the change of the temperature and crack healing ability.First, after the composition design of asphalt concrete mixed with three different types of steel wool, the steel wool used 3.5 mm and 6.5 mm 2 # steel wool and 3.5 mm4#steel wool, and steel wool content including 2%, 4% and 6%, through the study of composition design and mixing process determining the best mixing way and mixing time.Second, the mechanical performance test experiment of asphalt concrete mixed steel wool was carried out, in order to study whether the addition of steel wool have a negative impact to the asphalt concrete and the influence law. Mechanical properties test research, such as high temperature, low temperature and water stable performance,shows that different type and dosage of steel wool has different influence on mechanical performance of asphalt concrete, such high temperature and water stability performance with steel wool of a certain dosage is increased, while the low temperature performance due to the addition of steel wool shows negative effect.Then, based on the induction heating efficiency test on the Marshall specimen and beam specimen of asphalt concrete mixed steel wool, researching the heating temperature scattered and change of the specimen under the condition of the induction heating, including temperature gradient and the rate of temperature rise and fall. After determining the rate of induction heating, beam specimen is heated to 50 ℃, 60 ℃,75 ℃ and 90 ℃, using three point bending test to study the healing performance of induction heating asphalt concrete, the test shows that induction heating can increase the healing properties of asphalt concrete with steel wool in different degrees.Finally, combining the mechanical properties and induction heating healing properties of asphalt concrete mixed steel wool, the optimization design for the mixed steel wool is proceeded for studying the best type and dosage of steel wool.