Malaysian Journal of Geosciences (MJG)

Assessment into the source of building failure was conducted within the Bauchi metropolis, northeastern Nigeria. Recently, the loss of lives and properties in the area was due to building failures. Geotechnical, geochemical, mineralogical, and geophysical methods of investigations were employed to test likely features responsible for this anomaly. Results from sieve analysis showed that the proportion amount of clay ranges from 1.0 – 70.0%, Optimum Moisture Content (OMC) ranges from 9.3 – 15.3%, Liquid Limit (LL) 25.8 – 43.2%, Plastic Limit (PL) 20.8 – 34.2%, Plasticity Index (PI) 4 – 14%, Maximum Dry Density (MDD) 1605 – 2005 kg/cm3, specific gravity (SP) range from 2.7 to 2.8%, permeability (k) 2×10¯5 to 21×10¯5 m/s. Triaxial test result also shows high cohesion values of 81.30105.00 kPa, and low angle of internal friction in the range of 11.750 – 20.460, with a low bearing capacity of 35-209 KNm2. Clay mineral predominates the studied soil as smectite shown by X-Ray Diffraction (XRD). Results from Vertical Electrical Sounding (VES) revealed a three-layered formation, comprise of Topsoil, with resistivity values ranging from 64.13 to 352 m, and a weathered layer (saprolite), with resistivity of 11.99 to 118 m and fresh Basement. Hence, a significant amount of smectite with high swelling and shrinkage potential, low permeability, and low resistivity among others as factors responsible for the basis of building failure experienced in the study area. These make the soils unsuitable for siting of a building. Thus, the need for stabilization and improvement before building construction.