Development of Sustainable and Eco-Friendly Materials from Termite Hill Soil Stabilized with Cement for Low-Cost Housing in Chad

Abstract

This paper explores the effects of cement stabilization (5, 10, 15 and 20 wt%) on the structural and mechanical properties (compressive/flexural strengths and fracture toughness) of abandoned termite mound soil. The crystal structures and crystallinity of the constituents were determined using X-ray diffraction (XRD), while the microstructure was characterized via scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). The functional groups were also identified using Fourier transform infra-red spectroscopy (FTIR). The compressive/flexural strengths of the stabilized and un-stabilized termite mound soil were also studied after curing for 7, 14 and 28 days. The fracture toughness mechanism was analyzed with the aid of the R-curve method. Additionally, the underlying deformation and cracking mechanisms are elucidated via in-situ/ex-situ optical and scanning electron microscopy. The stabilized termite mound soil displayed the highest mechanical properties of 13.91 MPa, 10.25 MPa and 3.52 kPa·m1/2 for compressive strength, flexural strength and fracture toughness, respectively. Besides displaying good mechanical properties and being locally available at no cost, renewable and an eco-friendly material, the termite mound soil will contribute to lowering the cost of housing in Sub-Saharan Africa, particularly in Chad.

Dimensionnal stability and strength appraisal of termite hill soil stabilisation using hybrid bio-waste and cement for eco-friendly housing

“…The processing of the termite hill's soil and the results of its Atterberg limits, particle size distribution, moisture content, density are presented in Figure 1 . Meanwhile its chemical composition is reported elsewhere [ 6 ].

Figure 1 Physical characteristics of the termite hill soil.

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“…Hence, the morphology, chemical component and existing bonds were examined through scanning electron microscope (SEM)-energy dispersive spectroscopy (EDS) and Fourier transform infra-red (FTIR) respectively. Those characterizations have been proceeded on a Thermo Scientific Nicolet iS5 FTIR system (Thermo Scientific Nicolet, Worcester, MS, USA), Carl Zeiss Model EVO LS10 (Carl Zeiss, Pleasanton, CA, USA) for the FTIR and SEM-EDX respectively as reported elsewhere [ 6 ]. All the microstructural observations were carried out on the mechanically tested samples at 28 days.…”

“…[ 5 ] resulting in very expensive and detrimental materials. The conventional construction materials are not accessible and affordable in some eroded regions [ 6 ] (some sub-Saharan African countries). Consequently, these precited problems motivate to consider/promote the development of eco-friendly materials.…”

Innovative Industrial Use of Bamboo as Key “Green” Material

“…The search for solutions related to alternative materials has turned attention toward bamboo as a reinforcing material. Organic waste (e.g., bamboo leaves or a mixture of straw) can be used, after thermal activation, during cement production and have been identified as a cheap alternative to the production of composites reinforced with natural fibres and as significantly improving the mechanical properties [40]. The values of the mechanical properties for bamboo presented in Table 1 are given in numerical intervals, because their value depends on the diameter of the culm and the wall thickness of the tested material sample.…”

Mineralogical, geochemical, and geotechnical features of lateritic soils from termite mounds in two contrasting savannah areas (central Cameroon) as raw materials for brick making

“…Termite mound soils are used as fertilizer in agriculture, material for brick manufacturing, research of groundwater, and prospection of mineral resources like gold and diamond [ 5 ]. Numerous studies focus on termite mound soils as raw materials for construction [ [6] , [7] , [8] ]. Millogo et al [ 6 ] show that those from Kofila in Burkina Faso are made up of quartz, kaolinite, and feldspar.…”