FLY ASH-BASED GEOPOLYMER FOR SUSTAINABLE SUBGRADE STABILIZATION: PHYSICAL AND MECHANICAL PROPERTIES

Low soil bearing capacity can accelerate road damage and reduce efficiency, especially with high traffic. This percentage is lower than minimum California Bearing Ratio (CBR) of 6% needed for subgrade soil, according to Revised Road Pavement Design Manual No. 02/M/B/2017. Consequently, the problem was addressed by using fly ash geopolymer that chemically bond with soil particles to increase soil strength and contribute to waste management. Therefore, this research aimed to assess stabilization capacity of fly ash geopolymer and examine the effect on mechanical and physical properties of subgrade soil Mechanical property were assessed using unconfined compressive strength (UCS) test at 0, 7, 14, and 28 days of curing. Meanwhile, physical and material characterizationwere examined using plastic limit, liquid limit, X-ray diffraction (XRD), and Scanning Electron Microscope-Energy Dispersive X-ray (SEM-EDX). This research utilizes fly ash as an environmentally friendly construction material, supporting waste management and sustainable development with wide application potential.