Journal Article

Clayey soils from Boulgou (North Cameroon): geotechnical, mineralogical, chemical characteristics and properties of their fired products

Kagonbé Pagna, B., Nzeukou Nzeugang, A., Balo Madi, A., Nkoumbou, C., Tsozué, D., Ngos, S., Fagel, N., Fankam Deumeni, A.

2021

Overview

In this study, clayey soils are characterized as backfill and potential fusible raw materials for engineering. Geotechnical tests (particle size distribution, Atterberg limits, densities) and chemico-mineralogical analyses (X-ray fluorescence, X-ray diffraction and Fourier transform infrared) were carried out on samples collected from field in the locality of Boulgou (North Cameroon) followed by the determination of mechanical properties of fired bricks (850–1200 °C). The excavations carried out have revealed a thick layer of clayey soils (~ 2 to 2.5 m) over a sandy layer. This clay formation presents some stratifications with limited influence variation in terms of mineralogy. Mean grain size distribution is dominated by sand (62–80%), clay (12–25%) and silt (6–9%). It corresponds to silty–clayey soils regarding their methylene blue values (3.3–5.6), with low plastic (13–22%) to high plastic (33%) characteristics. They are classified by USCS as clayey sand/silty clay, while one sample is a poorly graded sand (SP). Clay minerals observed are kaolinite (6–12%), montmorillonite (2–6%) and illite (8–10%). Those parameters associated with their fine nature and high compressibility make them suitable engineering applications for backfill material and barriers. From chemical analyses, relatively high contents in alkali and alkaline earth elements (~ 4 to 6%) to be used as potential fusible raw materials for fired bricks or gres ceramics were revealed. Bricks characteristics are varied: linear shrinkage (0.3 to 9%), bulk density (1.8 to 2.3 g/cm 3 ), water absorption (19.7 to 1.3%) and flexural strength (0.3 to 17.4 MPa). Overall, the requirement for fired brick (< 20%) is met up by the water absorption values. As from 1050 °C, these soils are made suitable for brick-making with good characteristics (metallic sound, good cohesion and flexural strength).

• Publisher: Springer International Publishing,Springer Nature B.V,Springer
• Subject: 2. Earth and Environmental Sciences (general) / Absorption / Alkaline-earth elements / Altitude / Applied and Technical Physics / Atterberg limits / Backfill / Backfill material / Bricks / Bulk density / Cameroon / Ceramics / Chemical characteristic / Chemical Engineering (all) / Chemistry/Food Science / Clay / Clay minerals / Clay soils / Clayey soil characteristics / Compressibility / Earth and Planetary Sciences (all) / Earth Sciences / Earth sciences & physical geography / Engineering / Engineering (all) / Engineering applications / Environment / Environmental Science (all) / Fired products / Flexural strength / Fourier transform infra reds / Fourier transforms / General Chemical Engineering / General Earth and Planetary Sciences / General Engineering / General Environmental Science / General Materials Science / General Physics and Astronomy / Geology / Geotechnical tests / Grain size distribution / Illite / Infrared analysis / Kaolinite / Materials Science / Materials Science (all) / Mechanical properties / Methylene blue / Mineralogical analysis / Mineralogy / Montmorillonite / Particle size / Particle size distribution / Physical, chemical, mathematical & earth Sciences / Physics and Astronomy (all) / Physique, chimie, mathématiques & sciences de la terre / Raw materials / Research Article / Sand / Sciences de la terre & géographie physique / Seasons / Size distribution / Soil compressibility / Soil layers / Soils / Water absorption / X ray fluorescence / X-ray diffraction