MEASURES TO REDUCE THE HIGH INCIDENCE OF STRUCTURAL FAILURES IN NIGERIA

Within the last few decades, Nigeria has been experiencing a great transformation in terms of population growth and the provisions of developmental facilities for the wellbeing of the masses. The built environmental sector was not left out in the process. This is because the construction of houses and infrastructures are essential to man next as air, water, and food (Salau, 1996). These structures served as residences, places of work, worship, entertainment, as means of transportation, etc. As the population and economic activities continued to explode, the demand became more pressing. This justified the massive housing and infrastructural development that has been going on in the urban and rural areas of the country in the recent times. But an embarrassing feature of our building and infrastructural developmental strive is the failure rate verified among the existing structures and those under construction. The cost of these collapses, in terms of human life and economic waste, cannot be over emphasized. As the effect of the global warming began to take its toll in many parts of the world, including Nigeria, the need to arrest this ugly situation in our built environment becomes very expedient (Ede, 2010). In light of these issues, this paper analyses the problems of structural integrity in Nigeria as the environmental setup worsens and proffers measures bordering on the improved professionalism and craftsmanship that will reduce the menace drastically

Building Collapse in Nigeria: the Trend of Casualties the Last Decade (2000 -2010)

Over the last 10 years, the incidence of building collapse in Nigeria has become so alarming and does not show any sign of abating. Each collapse carries along with it tremendous effects that cannot be easily forgotten by any of its victim. These include loss of human lives, economic wastage in terms of loss of properties, jobs, incomes, loss of trust, dignity and exasperation of crises among the stake holders and environmental disaster. It can be rightly said that any pursuit of human endeavor has its cost, but the cost being paid in the Nigerian building industry cannot be justified. The fact that Nigeria is undergoing a tremendous transformation in the built environment cannot be over emphasized. This is in line with the growth that is being experience in the infrastructural and building industries all over the world for the effects of technological breakthroughs and consequently the ICT flattened world. But experiencing negative trends in the Nigerian building industries while other parts of the world are experiencing total improvements brings to fore the need to come out boldly and confront this ugly situation. The world today is facing a lot of other more serious man-made and natural crises such as global climate change which requires greater preparedness than the level on which we are standing today. For these facts, this paper addresses the impacts of building collapse on Nigerian strive for sustainable developmental. Probabilistic model of the linear regression analysis was used to establish the trend of heights and casualties. The results of this research will go a long way in reducing the building collapse phenomenon and the implications on the efforts of the nation to achieve the Millennium Developmental Goals (MDGs) and the Vision 20-2020

Acceptability of Plastic Materials for Structural Applications in Nigerian Buildings

In lieu of the fact that plastic materials have many unique properties, they are in several new applications. This research studied the application of plastic materials in Nigerian building industry, the extent to which plastic products are being used in Nigeria for structural elements in building construction and factors affecting the choice of plastic materials in the Nigeria building industry. This was done through the distribution of questionnaires and interviews with key persons in the construction sector in order to map their perceptions and personal experience. Companies, research institutes and building sites using various forms of plastic material for building construction were visited. Statistical methods were used to analyse the data. The outcome of this research shows that the level of acceptability of plastic materials in Nigerian construction industry for structural purposes is not very good. Polyvinyl chloride and polystyrene are the most used plastics and they are applied in pipes, finishes, ceiling, wall panels, windows and doors while advanced plastic materials such as fibre reinforced polymers are not widely used

Cumulative Damage Effects of Truck Overloads on Nigerian Road Pavement

Road infrastructure is one of the basic facilities needed for the growth and advancement of any modern economy. The growth of every country’s economy is measured by the growth of it’s transport infrastructure. This is very true of Nigeria as the state of failed roads all over nation gives a clear picture of the situation of the economy. The road network system has so failed that travelling within any part of Nigeria has turned to be the most assiduous venture for the citizens to undertake. For these reasons, this research examines the devastating effects of truck overloads on the road pavement failure in Nigeria. This research analyses the axle loads of heavy vehicles on Lagos- Ibadan Expressway to see how they influence the state of the road’s pavement condition. The expected pavement load was quantified through equivalent single axle loads (ESALs). Analysis of the data resulted in the existence of high vehicle damage factors caused by overloaded heavy vehicles

Building Information Modeling: Case Study of a Duplex Building Project in Nigeria

Activities involved in construction projects have always been complex and continue to be yet more complex for the high level of sophistication the world have attained today. As the desires of man continue to expand, so do the interests of the stake holders in the built environment industry. But the vast advances in the Information and Communication Technology (ICT) have brought about substantial amounts of research on approaches and applications to reduce the burdens of the built environment complexities. One of these new advances is the Building Information Modeling (BIM). BIM unites Design, Construction, Maintenance, Management and Documentation of building projects thereby enhancing better informed decisions by the project team players and improving the end product. This research engages Building Information Technology on a modest duplex building project. The results obtained demonstrates that Building Information Modeling breaks distance barriers between the team players working on a project, enhances safety, economy, beauty and eliminates waste

Appraisal of Timber as Structural Members for Residential Buildings in Nigeria

Concrete and sand crate blocks are the most common construction materials adopted for residential buildings in Nigeria. They are used in the form of reinforced concrete frames and sand crate block walls. These heavy weight materials are mostly assembled on site by bricklayers or masons. The high demand for these construction materials and the intensive labour required for site placement have led to high cost of these materials and consequently to general high cost of construction in Nigeria. These facts contribute to making the access to good housing by common man very difficult. It therefore becomes very obvious that alternative means of construction should be explored and implemented in order for the average and below average Nigerian citizen to have a decent roof over their heads. Based on the rapid advances in the construction materials technology over the recent years, civil engineers have been enabled to produce new solutions of built structures to serve the common needs of society. In that line, this research work seeks to provide an alternative solution in timber as a load bearing member for affordable residential buildings in Nigeria. A case study of 5-bedroom duplex is presented. A concrete design with Orion R16 software and a manual timber design are produced for the building with the corresponding bill of quantities. The comparative studies show that the application of timber as a structural members will help to drive down the cost of residential buildings in Nigeria and make them affordable to common man

Challenges Affecting the Development and Optimal Use of Tall Buildings in Nigeria

Since late nineteenth century till date, major World cities have been growing in size and in height. Tall buildings have become a prominent feature in any city of economic or political importance. This has been in response to the ever pressing need for greater accommodations in vibrant economic cities and for the acute scarcity buildable land in major urban areas. USA pioneered the growth tall buildings more than one hundred years ago while the developing nations have taken the baton from the USA since the reasons that gave birth to the development of tall buildings are becoming more critical in the developing countries. This research therefore evaluates the challenges affecting the development and optimal use of tall buildings in Nigeria. Lagos the economic capital and Abuja the political capital of Nigeria are chosen for this research. Statistical methods were used to analyse the data collected and interesting results emerged from the research. A 100% absence of regulation for high rise construction and maintenance, about 90% lack of domestic expertise for high rise buildings, almost zero public supply of electricity and water were among the results obtaine

Use of natural resins in repairing damaged timber beams – An experimental investigation

Different techniques including the application of steel elements, composite materials and polymeric resins have been used in the past to repair damaged timber beams. However, there is a growing need to replace these materials with those with minimal environmental impact. In addition, stringent requirements of conservation authorities on the compatibility between repair and parent materials have also necessitated search for innovative repair materials for timber beams. Therefore, an increasing shift of focus towards the use of materials derived from natural sources in repairing and reinforcing timber structures is currently experienced. This paper presents the results of an exploratory study on the use of natural resins (rosin and bone glue) in repairing oak timber beams. 15 oak timber beams with cross section dimensions of 67 x 67 mm and 1100 mm in length were tested in four-point bending to failure. Undamaged, damaged (unrepaired) and damaged but repaired timber beams (with rosin and bone glue) were tested. The effectiveness of the repair material and technique was analysed based on the bending capacity and mid span deflection at failure. The initial results show negligible effectiveness of rosin in repairing timber beams. In fact, about 16% reduction (average) in load carrying capacity with a corresponding 5% decrease (average) in maximum displacement was recorded. Relatively higher level of effectiveness was recorded with the use of bone glue (about 10 % average increase in load carrying capacity). However, over 30% corresponding average increase in the maximum displacement was also recorded. Further work investigating different repair techniques and other natural resins is presently underway

Optimal Polypropylene Fiber Content for Improved Compressive and Flexural Strength of Concrete

Worldwide, concrete is a very important construction material, impacting heavily on Gross Domestic Products of many nations: a $30 billion business for ready- mix concrete production industry per year in the United States and a cement consumption rate of about 106kg per person in Nigeria. It is therefore imperative that this important material in the world construction industry must also be endued with the best possible properties. The principles on which reinforced concrete structural designs were based hangs on quality concrete material used in conjunction with quality steel or reinforcing material. However, in Nigeria, the reinforcement steel commonly used is of poor qualities as recent researches have shown that over 40% of 12 mm and 16 mm used within Lagos in 2010 failed the 460N/mm2 yield strength bench mark of BS8110 of 1997. The employment of micro fibers in the concrete will improve the strength and compensate for the apparently declining strength of Nigerian reinforced concrete building constructions and will also improve the strength of the non-reinforced concrete-sand crate block buildings. This research studies the effects of micro synthetic polypropylene fiber in improving concrete strength with the main focus of identifying the optimal quantity for improved compressive and flexural strengths of concrete. Destructive and non-destructive compressive strength tests and destructive flexural strength tests were carried out on the samples built with 0.25%, 0.5% 0.75% and 1% contents of polypropylene fibers alongside a control samples after 7, 14, 21 28 days of curing. The optimal percentage of polypropylene fiber that produced improved compressive and flexural strengths were found to lie within 0.25% and 0.5%

Structural Damage Assessment of FRP Strengthened Reinforced Concrete Beams under Cyclic Loads

Worldwide, the need for structural retrofit is on the rise and the use of Fibre Reinforced Polymer (FRP) composite material systems is becoming an accepted method for repairs, rehabilitations, and strengthening of deficient structures. The great qualities of the FRP materials, certified in the laboratories and confirmed in the fields have all contributed to propel the material as a very promising one, though more works need to be done to certify the fatigue resistance and durability criteria. This research looked at the experimental investigations of Reinforced Concrete (RC) beams strengthened flexurally with externallyepoxy bonded FRP laminates under four point cyclic loads. Dynamic tests are used to assess damages in the FRP-strengthened RC beams under cyclic loads. 6 RC beams of 150 x 200 mm cross-section and length of 2.20m and were reinforced with four 12mm ribbed longitudinal steel bars. Three types of FRP laminates made of high modulus carbon fibre, high strength carbon fibre and glass fibre were adopted. The results confirm that dynamicbased method is an efficient way of assessing damage evolution in RC beams strengthened with FRP laminates under cyclic loads. The results offered a criterion that can be adopted for quick assessment of the efficiency of FRP composite systems before applying them to civil applications