Integrated Geophysical and Geotechnical Methods for Pre-Foundation Investigations

Abstract

An integrated geophysical and geotechnical investigation for a proposed building foundation of an industrial plant layout was carried out to determine the competency of the subsoil as foundation materials. Electrical Resistivity Imaging (ERI) and soil analyses techniques were adopted. Two traverses of four Vertical Electrical Sounding (VES) points were carried out and 8 Boreholes for Standard Penetration Test (SPT) were drilled. In addition soil samples were taken at 1.5 m and 10 m depths and subjected to various laboratory analyses. Three geoelectric layers were delineated from VES including topsoil, saturated sandy clay soil and limestone. The SPT N value indicates that the relative density of the soils is medium dense to very dense while the result of the geotechnical analyses shows that maximum dry density of the soils range from 1680-1900 kg/m 3 and 1600-1850 kg/m 3 respectively at 1.5 m and 10 m while the optimum moisture content range from 14-19% and 13-19% respectively at 1.5 m and 10 m. The soils are silty sand with low plasticity depiting low to medium swelling potential. Conclusively, the subsurface on which the foundation of the industrial structures will be located within the study area is safe and fairly competent for any engineering work. Owning to the water lodge nature of the area it is advice that the building should rest on pill between 5 m and 10 m depth.

Application of Geoinformatics in Civil Engineering Design and Construction: A Case Study of Ile Oluji, SW Nigeria

“…Groundwater can influence the type of construction methodology that should be adopted to allow construction to proceed, knowing the depth of groundwater through groundwater assessment is good to know at the design stage and well before project/construction begins (Bell, 2007(Bell, , 2004Arora, 2008). Consequently, Geophysics and geotechnics through insitu and/or laboratory test are powerful tools used complimentarily in engineering site investigation (Coker, 2015;Olayanju et al, 2017;Alabi et al, 2017;Adewuyi and Philips, 2018;Adejumo et al, 2015). Geophysics can aid in the detection of anomalous regions linked with important subsurface characteristics.…”

Seismic Risk Analysis of Hospital Buildings: A Novel Interval-Valued Spherical Fuzzy ARAS

“…C3 Foundation system. Foundation system is also an important part of a structure which transmits vertical loadings to the soil and may be responsible for failure under seismicity [30].…”

Assessing the physical and geotechnical properties of subsoils within an active municipal solid waste dumpsite for secured future urban growth

“…The stability of engineering structures depends on factors such as foundation design, nature of building materials, geotechnical behaviours of receiving sub-soil amongst others [25,26]. Soil provides the needed support for engineering structure placed on it, thus the need to check the suitability of near surface soils that are used for foundation, landfill liner or as a construction materials [27][28][29][30]. In addition, the durability and strength of building materials is a function of its efficiency in response to the load placed on the near-surface soil, thus a detailed understanding of the soil properties with depths will provide needed information to avert likely engineering and environmental problems [23,29].…”