‘Partially demolished buildings risk collapse’
Deeply worried about on-going improvements in old buildings or partially demolished buildings across the country, experts have warned that living in such structures pose risk of collapse, loss of life and property.
They told The Guardian, that building sliced into half to accommodate road development doesn’t have full integrity anymore, describing it as a recipe for disaster and contribute to high rate of building collapse in the country.
Demolition, which is one of the most dangerous exercises in construction sector, comes by some natural or artificial forces like; storms, floods, fire accidents, as well as governments’ redevelopment efforts.
In cities, because of the need to improve infrastructure, attempts are made by authorities to expand the scope of existing facilities most especially roads to accommodate more users. As a result, residential and public buildings are often modified.
For instance, in places like; Lagos, Ibadan, Abuja, Kaduna, Port Harcourt and Kano and others, major road projects have taken place or on-going after officials partially demolished buildings.
The aftermath of such efforts is that owners’ often embark on patching up of the affected parts to continue using the buildings.
According to them, modifying partially demolished buildings contribute to defects in the structural integrity of building.
Speaking on the issue, a past president of the Nigerian Institution of Structural Engineers, (NISTRUCTE); Mr. Kunle Adebajo, explained that modifying partially demolished building could be a major cause of structure collapse if existing occupants believe that the portion left standing can be satisfactorily be lived in without carrying out a test on the building by a certified structural engineer.
He said when the entire building is visually sliced into half to accommodate road development; the structure doesn’t have full integrity anymore. According to him, some of the structural supports must have been removed and a lot of instabilities could have set in.
Adebajo who chaired the institution for two years said; “In the process some buildings are not just demolished fully but some parts are cut off expecting the owner to re-do the remaining.
It’s almost like a person who goes into a room and because the room is filled, parts of the body is out of the room and somebody just comes and uses a knife to slice off that portion. There is no way the rest of the body won’t feel it, it would have an effect like structural weakness”.
He said it is the responsibility of government and building owners to ensure that when some forms of demolition occurred; structural engineers should be brought in to advise on necessary steps to take on the building to avoid disaster.
“Government must involve their own engineer to ensure that when they are breaking or partially breaking, they would not leave a structure that is exposed and unstable to the environment.
For example, the staircase must have been tapered with. Valuable parts that should be examined include, the structural frames, and support system to make sure that every part is intact. The structural beam supports must be examined as well as full fundamental engineering assessment”, he stated.
Also speaking, a civil engineer based in Ibadan, Dr. Bamidele Dahunsi said before owners are allowed to live in the building, there should be a regulation that would subject the building to integrity test to determine whether they could still perform their function.
“From the structural perspective if the process of demolition is not well controlled, some of the major elements must have been weakened and it means those ones could be a time bombs ready to blow up anytime”.
According to him, from visual observations, the buildings might look good, but needs to be subjected to further tests to confirm that nothing has happened to them internally because most constructions are framed adding that the removal of some columns could have reduced the structural integrity of the building.
“It is not enough to just cut part of the building without seeing if the remaining part would still perform its natural functions.
Government needs to ensure that the buildings are still fit for the purpose which they are meant but nothing like that is been done we just have a situation in government demolishes and pay some compensation but rather than for the owners to move out, they continue to stay in”.
“Major structural elements like the slabs, the beams or the decking must be checked. If a building is amputated but still satisfy the structural requirements, there might not be need for complete uproot.
There might be need to convert the use of the building to a low capacity usage if the building is partially demolished but still appear to be structural fit”.
In his views, an associate professor, department of civil engineering, University of Ibadan, Festus Olutoge said for longevity of buildings non-destructive testing must be carried out to forestall building collapse in the future.
Speaking on the development, the General Manager, Lagos State Physical Planning Permit Authority (LASPPPA), Mr. Funmi Osifuye told The Guardian that those affected need to get directives from relevant building authorities on plans to refurbish the remaining property.
Osifuye who ensures that all property owners in state obtain necessary building permit said; “The first thing is to test the remaining part of the building for stability, consult engineering company or the Lagos State material testing agency to check the structural members of the remaining part of the building and obtain new permit for the new structure.
They will also need to consult Lagos State Building Control Agency (LASBCA) to supervise and ensure that what they are doing comply with the law”.
He said by re-modification, initial approval has been nullified because what is on ground doesn’t tally with what had been submitted to government.
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