MANY WAYS WHY BUILDINGS COLLAPSES IN NIGERIA
July 20, 2016
Building collapse in Nigeria has been on the increase in recent times. There are frequent media reports of collapsed buildings in major Nigerian cities and other parts of the world. The reasons a building collapses can be due to poor structural design, poor compliance with specifications, poor quality control, faulty construction methodology, foundation failure, and corruption. Natural disaster is also identified as a cause of building collapse.
There have been several recent cases of building collapse in Nigeria, a few of which, as reported, are as follows;
The Synagogue building collapse: A six‐storey building under construction belonging to Synagogue Church of All nations collapsed in Lagos on September 12, 2014 with reports of over 100 deaths and over 100 injured.
Jos school building collapse: On a Sunday evening in September 2013, a school building belonging to Abu Naima Primary and Secondary School in Bukuru, Jos South Local Government Area collapsed. About 30 pupils below the age of ten were reportedly killed in the ugly incident
Building collapse in Ebute Metta, Lagos: A 4-storey building, popularly called “Titanic”, collapsed in July 2006, with reports of over 28 fatalities
According to various studies carried out to date, the following are the structural engineering design and construction related reasons for building collapse as listed by building professionals in Nigeria:Buildings, like all other structures, are designed to support loads and to resist external forces without excessive deformation. These loads are the weights of people and objects, weight of rain and wind pressure; all generally referred to as live loads and the weight of the buildings themselves; generally referred to as DEAD LOADS. All these loads must be incorporated into the structural design such that the building can hold up these loads during its life time. The Design Life for structures is typically fifty (50) years.
pool Structural Design –
These are not only errors of computation, but a failure to take into account the loads the structure will support, 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 design stage. At MO&A, before the structural design is concluded, there are different stages of Quality Assurance and Quality Control QA/QC reviews through the Concept/Preliminary Design stage, the Design Development stage, and the Construction Documentation stage. Peer reviews of the design are dutifully and diligently conducted, and a formal sign-off is generated at the completion of each gate review.
Poor compliance with engineering drawings and specifications – When structural drawings and specifications are not judiciously followed during construction, it is detrimental to the life of the structure. To avert the threat of collapse, it is important that the engineer produces explicit, clearly documented and easy to understand details of drawings which should also be made promptly available to the contractor whenever needed.Use of sub‐standard building material – In order to avoid the use of substandard material, samples of materials to be used for construction should be subjected to all the compliance tests, viz chemical, strength, composition, etc., to ascertain the integrity of the materials. For example, aggregates to be used for construction should be checked for contaminants like chloride and other impurities. To prevent retardation of compressive strength of concrete, no material with chloride should be used. Also, steel reinforcement should be tested for compliance with standards regarding its tensile strength and ductility.Inadequate supervision of construction work & poor quality control – The supervision phase is very important because the life of the building depends on it. The placing of concrete, the vibration of concrete, the fixing of reinforcement, the concrete cover provision, workability of concrete etc. are all checked to be sure that they conform with the specifications in the drawings. In practice, MO&A consistently provides thorough and adequate supervision of the activities of the contractor regarding any construction work. The supervising engineer ensures that the contractor works in line with the specifications of the construction drawings and clarifies to make sure there is no misunderstanding or miscommunication about the drawing or any aspect of their work.
Illegal conversion/alteration/addition to existing structure
– The illegal conversion of an existing structure for uses other than the original design intention and use. For example, a building that was originally designed to bear three floors and later converted to bear two additional floors, without consulting a structural engineer, may collapse due to overload and consequent over stress of the foundation. The foundation may have been designed to bear only three floors without taking future expansion into consideration. It is pertinent to note that it is the duty of the Structural Engineer to certify the structural integrity of a structure, especially when it comes to changing its use.
Corruption – Sometimes drawings and specifications are not effectively or adequately reviewed by authorizing officers in the chain of approval grants. Corrupt practices tend to be one of the undermining factors in such regard.
Natural disaster
– In Nigeria, the most common natural events are heavy winds, rain storms, floods, earth tremors, etc. Unanticipated impact loading from these different causes, and the erosion from flooding have been recorded as contributory natural causes.
Poor construction
– This arises when contractors fail to carry out work in accordance with the Consultants’ specifications. It is commonly believed that they do so to further maximize profit, with often fatal consequences. Sometimes specified materials are substituted with sub-substandard ones. Other areas of concern include poor concrete mixes, premature removal of formworks and general poor workmanship.
Poor Maintenance – Buildings begin to deteriorate from the time they are completed and need timely maintenance to remain in good condition. A process of gradual deterioration is unavoidable, but the speed at which it progresses can be reduced through proper and timely maintenance.
Poor building maintenance can cause weakening of the building structure.
Lack of genuine geotechnical information about the underlying soil – A reputable Geotechnical expert should be consulted when a soil test is needed. This is because the structural engineer will solely rely on this result to design the suitable foundation based on the recommendation of the geotechnical engineer. Even an excellently designed and constructed structure will not stand on a faulty foundation. Although the structure may bear the loads, the earth beneath may not. The displacement due to faulty foundations may alter the stress distribution significantly.
In order to avoid the collapse of buildings in Nigeria, the following, as part of a larger scope, is recommended:
Proper planning, supervision and monitoring of construction activities should be institutionalized by policy makers to ensure that all buildings are constructed according to design, specifications and planning regulations.Urban or Town development agencies at various levels of government (commission, Board, Authority) should enforce control of building works in their localities as laid down in urban and regional planning decree 88, of 1992 and as in section 13 of National Building Code 2006.Periodic public awareness campaigns through electronic and print media to educate the public on the advantages of using qualified professionals as the only way to achieving the goal of having safe buildings in our neighbourhoods.Standard organization of Nigeria (SON) should be vigilant to ensure that building materials imported into the country meet standard requirements.All building professionals should fulfil their respective obligations during building construction.Soil investigation, material tests and environmental impact assessment (E.I.A) should be made mandatory for all institutional, industrial and commercial buildings.A review of existing building laws to guide standard codes of practice and cover all grey areas in order to guarantee safety of buildings and people in our country.
Although there are parts to play by various sectors involved with building construction in Nigeria, the key ingredient is the need for more effective government regulation of the industry. Engineers playing their roles, as is being done, can certainly not be enough to stem or arrest the tide of incessant collapse in the Country. If only governments can grant a similar level of empowerment as obtains in the banking and pharmaceutical industries, and the Oil and Gas Sector, to the building and construction industry, the Country will be so much better for it and the wave of collapses will blow away, or reduce to insignificance.
Edu building project. designs and plans we use the right material for the right work. Call us on 07067985359 we give you the best building work in around the world.
