Physics http://ir.library.ui.edu.ng/handle/123456789/358 2025-09-27T08:34:42Z 2025-09-27T08:34:42Z Adebo, B. Adetoyinbo, A. http://ir.library.ui.edu.ng/handle/123456789/9341 2024-06-24T11:47:18Z 2017-01-01T00:00:00Z

Title: Groundwater abstraction: a model for saltwater intrusion of coastal fresh water Authors: Adebo, B.; Adetoyinbo, A. Abstract: The knowledge of salinity level and intrusion of saltwater into freshwater aquifer is necessary for groundwater monitoring and prediction in the coastal areas. In this work, an advection-dispersion saltwater intrusion model is used to study and simulate saltwater intrusion in a typical coastal aquifer. The aquifer portion was divided into grid with elements and nodes. Map of the study area indicating well locations was overlain on the grid system such that these locations coincide with the nodes. Chlorides at these wells were considered as initial nodal salinities. Results showed a highest and lowest increase in simulated chloride of 37.89 mg/L and 0.8 mg/L respectively. It also revealed that the chloride concentration of most of the considered well may climb unacceptable level in the next few years, if the current abstraction rate continues unabated

2017-01-01T00:00:00Z Adetoyinbo, A. A. Bello, A. K. http://ir.library.ui.edu.ng/handle/123456789/9340 2024-06-24T11:46:50Z 2019-06-01T00:00:00Z

Title: Determination of temperature profile of the lithosphere between zero and 150 km penetration at Itagunmodi, Nigeria Authors: Adetoyinbo, A. A.; Bello, A. K. Abstract: In this work the temperature profile for the lithosphere was determined using data from radiogenic heat source and heat from other sources from 0 to 150 km depth was determined using a suitable mathematical expression. The temperature at the base of the lithosphere was given between 1200°C to 1600°C. The Fourier’s law was applied and the results showed that the profile range from 27.0°C to 1483.3°C. These results compared favourably well with existing literature values.

2019-06-01T00:00:00Z Adetoyinbo, A. A. http://ir.library.ui.edu.ng/handle/123456789/9339 2024-06-24T11:39:11Z 2019-07-01T00:00:00Z

Title: Assessment of building failure within and around quarries Authors: Adetoyinbo, A. A. Abstract: The substructures of various engineering structures that were erected on the earth are being were been supported by the soil. Hence, the nature of the soil supporting these structures becomes an important issue. Quarry blasting peak particle velocity (QBPPV) is not sufficient to ascertain the causes of foundation failure, therefore, the physical parameters governing the competency of the soil supporting engineering structures need to be determine. This work investigated the possible causes of foundation failure of buildings within the vicinity of quarries. The investigation was done by carrying out Vertical Electrical Sounding (VES) and Radial Vertical Electrical Sounding (RVES) using Campus omega terrameter. The results show that buildings found within this area have shallow foundation and their foundations founded on sandy clay which can still support foundation The values of the degree of fracturing was found not to exceed 1.53 in this region which was not the case with the previous radial vertical electrical soundings, 1.94 was calculated as the highest degree of fracturing for RVES 1 while 1.83 was calculated for RVES 2. In all the RVES, degree of fracturing ranges between 1.02 to 1.94.

2019-07-01T00:00:00Z Soge, A. O. Popoola, O. I. Adetoyinbo, A. A. http://ir.library.ui.edu.ng/handle/123456789/9338 2024-06-24T11:35:23Z 2019-05-01T00:00:00Z

Title: A four-point electrical resistivity method for detecting wood decay and hollows in living trees Authors: Soge, A. O.; Popoola, O. I.; Adetoyinbo, A. A. Abstract: An accurate method of detecting wood decay and hollows or cavities in living trees is useful for risk assessment and maintenance of both forest and urban trees. This study presents the implementation of the four-point electrical resistivity method for the early detection of the presence, location and extent of wood decay and hollows in living acacia trees (Senna cilata L.). Electrical resistivity measurement of randomly selected living acacia trees and a freshly-cut acacia tree with decay and hollows were taken to obtain electrical resistivity profiles for sound, decayed and hollowed trees. A laboratory experiment was set up to replicate the resistivity profiles. Wood decay and hollows were replicated at different depths in the laboratory prototype using good electrical conductors and insulators respectively. Resistivity profiles for the sound, decayed and hollowed trees were obtained from the experimental and field results. The resistivity profiles were applied to detect decay and hollows of similar dimensions in living trees through resistivity curve matching. The electrical resistivity of the decayed acacia tree was markedly lowered by an average factor of 5 compared to that of the sound acacia tree. Likewise, the electrical resistivity of the hollowed acacia tree was noticeably greater than that of the sound acacia tree by an average factor of 4. Wood decay and hollows modelled into the laboratory prototype were detected with relatively lower and higher resistivity anomalies respectively. The method indicated that 80% of the randomly selected living trees were sound, healthy trees, whilst 20% had decay and hollow at the time of measurements. This method is suitable for early detection of decay and hollows in hardwood trees.

2019-05-01T00:00:00Z