Abstract:
In the last few years, there have been incessant reports of the collapse of buildings resulting in the loss of lives and properties in Nigeria. There has, however, been a dearth of information regarding any findings about the collapse of the building structures.
An extensive study of causes of selected building collapse in Nigeria and abroad
is carried out in the work. Questionnaires were used in the investigation. Also used
were oral interviews, site inspections, appraisal of the structural drawings and
laboratory tests on materials collected from the collapsed building sites.
The results show that over-reinforcement and over loading contributed to the
col/apse of the buildings. The average concrete crushing strength of these materials
was measured as 4.9N/mm2, which is much lower than the code required minimum
strength of 21 N/mm2 for the assumed 1:2: 4 mix proportion. In addition, the coarse
aggregate used in the construction contained impurities like biotite and muscovite,
which are easy oxidizing agents capable of accelerating building collapse. However, the
bearing capacity of the soil measured between 140kN/m2 - 260kN/m2 indicating that
the soil is adequate to support the building foundations. The followings are also identified as some of the causes of building collapse: the use of inferior building materials, inadequate planning and design, poor management and workmanship, improper supervision during construction, occurrence of natural disasters such as earthquakes and improper use of explosives. Based on the results obtained through this study as well as the recommendations on them, the further occurrence of building collapse will be greatly reduced.
