Geopolymer-based soft magnetic material, preparation method thereof and application of geopolymer-based soft magnetic material in detection of asphalt pavement base crack width

The invention discloses a geopolymer-based soft magnetic material, a preparation method thereof and an application of the geopolymer-based soft magnetic material in detecting the width of a crack of an asphalt pavement base. The geopolymer-based soft magnetic material is composed of soft magnetic powder and geopolymer slurry and is arranged on a traditional asphalt pavement base layer. Wherein the soft magnetic powder is iron powder with the particle size of 10-200 microns, and the geopolymer slurry is mainly composed of water, fly ash, granulated blast furnace slag and an alkaline activator. The mass ratio of SiO2 to Al2O3 in the geopolymer slurry is 0.35 to 0.50. The road base crack direction and width condition can be directly obtained by combining a vehicle-mounted fluxgate sensor, comprehensive, rapid and nondestructive detection on the base crack is achieved, and the road base crack detection device has the advantages of being low in cost, high in reliability, energy-saving, environmentally friendly and