Geopolymer-Cold Regeneration Strengthening Process of Heavy-load Transportation Road in Open-pit Mine and Its Application

In view of the current existing problems of low efficiency, poor quality and others in roads of open-pit mines, a new type of geopolymer-cold regeneration machine road construction process is proposed. Through a series of tests such as pavement material screening test, aggregate compaction test, geopolymer mix ratio test, and delayed sample preparation test with simulated on-site working condition, etc, the optimal mix ratio of geopolymer raw materials is determined: when the modulus of alkali activator is 1.75, slag fly ash accounts for 12%, moisture content is 11%, and alkali activator accounts for 70%, and the construction application is conducted on the 1055 test road section of Ha’erwusu Open-pit Coal Mine. The on-site soil foundation load-bearing plate test and road drilling core sampling test results indicate that the road surface roughness, load-bearing capacity, and durability are significantly improved, the uniaxial compressive strength is improved from 5 MPa of the original road to 15 MPa, and the rebound modulus value is improved by more than 50%. Compared with the traditional process, the material cost of this process is decreased by over 50%, providing an efficient, economical, and environmentally friendly solution for the road construction in open-pit mines.