Evaluation of the microstructural and physico-mechanical characteristics of cement-stabilized termite hill soil for construction application

Abstract

This study investigates the potential of termite hill soil (TS) as an environmentally friendly alternative to cement. By reducing reliance on cement, this approach could decrease the environmental footprint of the construction industry. Portland cement was used to stabilize TS at contents of 5%, 10%, and 15% by weight (wt%). Key engineering properties of the stabilized and un-stabilized specimens were analyzed to assess the suitability of TS for construction applications. Physical properties were evaluated using particle size distribution analysis, dimensional stability testing, and density measurements. Microstructural analysis employed Scanning Electron Microscopy (SEM) coupled with Energy-Dispersive X-ray spectroscopy (EDX), Fourier Transform Infrared (FTIR) spectroscopy, and X-ray fluorescence (XRF) to investigate the effects of stabilization on the microstructure and its influence on bulk properties. Compressive and flexural strength tests were conducted to assess the mechanical properties of the specimens. Compressive strength results showed that the 10–15 wt% stabilization level achieved the highest values, reaching 3.81 MPa, 4.58 MPa, and 5.91 MPa at 7, 14, and 28 days, respectively. Flexural strength values for the same specimens at these curing times were 0.98 MPa, 1.72 MPa, and 1.94 MPa, respectively. The findings of this investigation can serve as a reference for treating other soils to achieve properties similar to TS, making them suitable for durable construction applications. Additionally, this study demonstrates the feasibility of developing and using TS as construction material for housing solutions in regions with abundant and currently undervalued termite hill resources.