Maduka Nweke, [email protected] 08034207864, 08118879331
Every year Nigerian families across the country have been made to mourn the loss of loved ones not through wars or pestilence, but from the collapse of building under construction or even older structures with structural defects. Available records show that the menace of building collapse has gone beyond the kid gloves handling given to it by the government. At all levels of government and authorities, professional groups or interest groups, have at one time or the other displayed their grievances, and in attempt to stop it, proffered solutions but all to no avail. This means that the only authority that can wield the big stick in the direction of stopping the menace remaines the government. Although the government has the power to handle it, it has either refused to wield the powers or the people in authority have refused to do the job.
Buildings, like other structures, are designed to support certain loads without getting excessively deformed. The loads are the weights of people and objects, the weight of rain and the pressure of wind – called live loads – and the dead weight of the building itself. Any type of building can collapse but multi-storey buildings are more prone to catastrophic collapse. Recent building collapses in Nigeria, are as a result of so many defaults both from government and private individuals.
As a matter of fact, building collapse has remained a source of concern to many stakeholders and the government. This is mainly because of the lives lost in some instances and the financial setback as well as the psychological impact on the citizenry. So government is duty bound to always check what plans are made for a building, the architectural design, which stipulates the number of floors, whether for residential, trading, manufacturing, religious practices and any other uses the house could be put to. Any time such original plans are not followed, government should not hesitate to take the required and stipulated action against defaulters. If this is done, it will serve as a deterrent to all other people trying to do same.
This is why states should provide guidelines on land use designation to guarantee orderliness in development. It is believed in some quarters that each state’s Ministry of Physical Planning and Urban Development (MPP&UD)’s rapid response to requests for planning information should ensure that the public is adequately educated on land use zoning, permissible use, plot size, building coverage and height, setback, airspace and parking requirements, in addition to other sundry standards for potential developments. These have helped in curtailing building collapse in some states.
The time has really come for Nigerians to desist from passing the buck or putting the blame squarely on poor quality cement, fake iron rods, greed of foremen to maximise profit and utter disregard for building and construction laws with intentional neglect for the safety of the occupants of such buildings to putting in place punitive measures to ensure engineers or architects who supervise the erection of such substandard buildings are made to face the full wrath of the law. It is time government does more than revocation of Certificate of Occupancy (C of O) of the land, which is a rarity nowadays where such substandard buildings are erected.
Some remote factors of building collapse include absence of soil test report, inability to carry out proper land survey, failure by foremen to understand and interpret building codes, lack of coordination between professional bodies like Standards Organisation of Nigeria (SON), Council of Registered Engineers of Nigeria (COREN), Council of Registered Builders of Nigeria (CORBON), Nigeria Institute of Architects (NIA), Nigeria Society of Engineers (NSE), among others, and government and local town planning authorities. Miserliness on the part of the owners (they shun professionals and use substandard materials to cut building costs), poor structural design, and non-compliance with approved building design are some of the major reasons for building collapse in Nigeria. We can stop looking for supernatural causes of structural failures and look within. They are human factors. If not for the lack of will to enforce the appropriate building regulations and the need to unnecessarily “manage” building costs, the probability of sudden collapse of building is relatively low even in the event of an earthquake or hurricane, according to geographers. Nigeria is at least blessed when we talk of soil textures. Every building contractor should be duly registered for easy tracking and punishment should there be a reoccurrence. It is as tragic as the structural failure in itself that the issues of building collapse in Nigeria are hardly ever taken seriously by the government or the relevant law enforcement agents.
Contrary to what many think, building collapses are not natural disasters except in cases of earthquake, hurricane or tornadoes but we thank God we don’t have such things here, at least, these years. The incidents in Nigeria are man-made and therefore avoidable. Buildings, like all structures, are designed to support certain loads without deforming excessively. So the consistency in having building collapse is as a result of governments not doing what they should do. Several times, government authorities are given some gratifications, which results to their perverting the regulations they came to enforce.
A story has it that some inspectors sent to supervise a three-storey building were taken to an eatery where they were treated beautifully. In their happiness, after some money changed hands, they forgot what they came for and left. Because they were in high spirit, they concurred to sign what they ought to have rejected, giving approval to an irregularity. Two more floors were added to the building, which they appended their signatures to against the stipulated foundation load. Five years later, the building pulled down completely from the foundation. This is pure human error that could have been avoided.
The loads are the greatest causes of building collapse because even human beings, when they carry more load than they can carry, you see them dunking. It is the same with buildings. The loads are the weights of people and objects, the weight of rain and snow in the western world, the pressure of wind called live loads and the dead load of the building itself. With buildings of a few floors, strength generally accompanies sufficient rigidity, and the design is mainly that of a roof that will keep the weather out while spanning large open spaces. With tall buildings of many floors, the roof is a minor matter, and the support of the weight of the building itself is the main consideration. Like long bridges, tall buildings are subject to catastrophic collapse.
Building collapse, according to some real estate experts, could also be as a result of bad design, faulty construction, foundation failure, extraordinary loads, unexpected failure modes and combinations of other factors. Bad design does not mean only errors of combination, but a failure to take into account the loads the structure will have to carry, erroneous theories, reliance on inaccurate data, ignorance of the effects of repeated or impulsive stresses, and improper choice of materials or misunderstanding of their properties.
The engineer is responsible for these failures, which are created at the drawing board. Faulty construction has been the most important cause of structural failure. The engineer is also at fault here, if inspection has been lax. This includes the use of salty sand to make concrete, the substitution of inferior steel for that specified, bad riveting or even improper tightening torque of nuts, excessive use of the drift pin to make holes line up, bad welds, and other practices well known to the construction worker.
Even an excellently designed and constructed structure will not stand on a bad foundation. Although the structure will carry its loads, the earth beneath it may not. The Leaning Tower of Pisa is a famous example of bad foundations, but there are many others. The old armory in St. Paul, Minnesota, sank 20 feet or more into soft clay, but did not collapse. The displacements due to bad foundations may alter the stress distribution significantly. Extraordinary loads are often natural, such as repeated heavy snowfalls or the shaking of an earthquake or the winds of a hurricane. A building that is intended to stand for some years should be able to meet these challenges. A flimsy flexible structure may avoid destruction in an area that is prone to erosion, while a solid masonry building would be destroyed. Erosion may cause foundation problems when moist-filled land liquefies.