NBRRI attributes Gwarinpa building collapsed to water-logged land, overloading
NAN-H-76
Collapse
By Constance Athekame
Abuja, Sept. 28, 2016 (NAN) The Nigerian Building and Road Research Institute (NBRRI) has attributed the recent building collapse in Gwarinpa, Abuja, to water logged land and “overloading from superstructure.’’
Mr Peter Mashem, Public Relations Officer of NBRRI, said this when he was speaking on the preliminary report produced by the institute with the News Agency of Nigeria (NAN) on Wednesday in Abuja.
NAN reports that a building under construction located at Jummai Kwanashie Crescent, behind Road 44 Citec Villas, Gwarinpa, Abuja, collapsed at about 1.00 a.m. on Aug. 29.
Mashem said that physical and reconnaissance survey was conducted and the observations were assumed based on the soil condition.
He said that report also attributed foundation failure from differential settlement as a result of overloading from the superstructure as one of the contributing factor to the collapse.
Mashem said that during investigation the team discovered that there were a lot of excavations around the footing of the ongoing structure that collapsed.
According to him, this could possibly affect the stress in the soil mass due to footing pressure.
He said that the Geotechnical Team visited the site immediately but was limited in carrying out all its functions due to the rescue operation going on as at the time of visits.
Mashem explained that access to the collapsed building was hindered by the security operatives.
According to him, the collapsed site which is located at plot 432 reserved as green area on a natural drained area.
“The site was converted to hotel, shopping mall and park for commercial purposes instead of green area,’’ he said.
He said the report listed the observations in the construction defaults as follows; nature of disintegration of concrete from the reinforcement members suggested a weak concrete mix.
According to the report, it appears the ultimate capacity of compression zone of the concrete is reached leading to flexural failure.
“Inadequate column sizes and inconsistency in the sizes of the columns; one size of coarse aggregate 20mm was used in the concrete mix throughout the construction; floor beams are also under reinforced.
“Structural members were not properly anchored together. This restricted the transfer of movement from the top floor down to the columns and into the foundation.
“As a result, movement is imminent and can lead to crack and pull out the reinforcement, which will make the members separate from one another,” he said quoting the report. (NAN)
COA/MO/AFA
Edited by Morayo Omolade/Felix Ajide
===========================