An Integrated Survey For Site Investigation At The Abandoned Senate Auditorium Of University Of Nigeria, Nsukka Behind Eco Bank And Uba

ABSTRACT

An integrated investigation involving electrical resistivity method, Induced polarization method, and triaxial tests were used to investigate an abandoned senate auditorium in university of Nigeria, Nsukka, southeastern Nigeria. This was with a view to determining or imaging the subsurface structure as they may cause instability and led to multiple cracks of the building. The building in the study area is intensively affected by severe cracks. The electrical resistivity and induced polarization method were carried out using Abem Terameter SAS 1000. The latitude and longitude data of each electrode position were collected and keyed into Google Earth software to imagine the exact spatial positions. In the study area the survey pattern was designed in a way that survey lines were carried out in a form of trapezium following the shape of the building fig.10, each of the profile lines was executed using a Wenner array method with a minimum electrode spread (a) of 10m and maximum of 30m and extended about 160m respectively.  The acquired data were processed and interpreted to elucidate the subsurface geologic structure of the study area. The interpretation of the data acquired led to the delineation of resistivity anomaly. The resistivity anomaly that is typically of a vertical structure (seemed to be a fault that filled up with low resistivity materials) was delineated along traverse one (fig.11) and three (fig.15), and it is surrounded with high background of high resistivity, showing fault zone. In profile line ERT2, it shows an inclined anomalous zone of relatively low resistivity fig.13. Profile line four is opposite of profile line two picked a similar low resistivity anomaly at the same spatial location. Fig.17. Data acquired in field were plotted using suffer 9 software to determine the 3D view of raw apparent resistivity, fig.12, 14, 16 and 18.  The traixial tests conducted on the soil samples collected at the same locations of profile lines revealed that there is a failure in the soil mass in which the building is erected.