Stabilization of marble wastes using cement and nano materials for subgrade applications

Marble has been widely used as a construction material for many centuries. Due to its wide use, managing of marble wastes has become a pressing issue for authorities as of the environmental threat driven by its increased stockpiles in roadside or abandoned lands. This study investigates a new use of marble waste in weak field soils as subgrade application using additive based stabilization. Raw marble waste was first stabilized with Fly ash based - Portland Pozzolana Cement (PPC) having various PPC content (0.5 to 10%) to investigate the behaviour changes of physical and mechanical characteristics. Then, the modified matrix with cement (1% and 10%) was further stabilized using nano materials of 0.1% reduce Graphene Oxide (rGO) powder by weight in order to enhance the strength properties. The improvements in strengths and mechanisms were characterised using detailed morphological studies to identify new formations of elements, functional groups and microstructure changes during stabilization process. Results showed significant increase of strength in the modified matrix (800% increase of CBR and 3 MPa increase of UCS from negligible strength) compared to raw marble waste due to the efficacy of adopted stabilization in the current study. Outcomes revealed that the novel marble matrix derived from this research using wastes and additives does not only indicate great potential in replacing weak subgrade soil which usually is the route problem for many road defects, but also provides an efficient solution for waste management crisis.