Feasibility and performance assessment of novel framework for soil stabilization using multiple industrial wastes

Abstract

The utilization of industrial wastes as feedstock for binders in soil stabilization is a promising approach toward environmental consequences; however, the optimization of chemical compositions and gradation are commonly disregarded especially for binders derived from multiple industrial wastes. This study presents a novel framework for designing multiple industrial waste blends (MIWB) consisting of ground blast furnace slag (GB), fly ash (FA), silica fume (SF), and calcium carbide residue (CR) and assesses its feasibility and performance in soil stabilization. The concept of three chemical moduli (TCM) and the strength activity index (SAI) are applied to control chemical composition, and Dinger–Funk particle size distribution is adopted to attain optimal gradation. A case study exemplifies sediment stabilization utilizing MIWB designed, and sodium hydroxide (NH), sodium metasilicate nonahydrate (NS), sodium sulfate (SS), and aluminum sulfate (AS) are used as chemical additives, the mechanical and microstructural studies by Atterberg limits, compaction, unconfined compressive strength, one-dimensional consolidation, cyclic wetting-drying, X-ray diffraction, scanning electron microscopy and nuclear magnetic resonance tests are comprehensively examined. The outcomes demonstrate that: (ⅰ) MIWB is more efficient than ordinary Portland cement (OPC) in enhancing the compressibility and durability of stabilized sediment, and the optimal mix design of the composite binder was 14.25, 47.5, 9.5, 23.75, and 5 wt% of GB, FA, SF, CR, and AS respectively. (ⅱ) The sulfate additives can dramatically improve the strength development of designed MIWB stabilized sediment than that of alkaline additives, (ⅲ) The C-S-H, C-A-S-H, and AFt crystals are identified as the primary reaction products, arising from pozzolanic reactions between active phases present in the industrial waste. (ⅳ)The pore volume of stabilized samples is reduced due to the excellent filling and cementation effects, contributing to higher mechanical properties. In particular, MIWB has been applied and proven effective in engineering practice.