COMPARATIVE ANALYSIS OF REINFORCEMENTS STEELS AVAILABLE IN ABUJA
CHAPTER ONE
INTRODUCTION
1.1 Background of the study
The choice of construction has always been an issue large in the mind of all self builders and has been a subject of debate in the industry, comparing the relative merits of masonry, timber and steel frame construction. Broadly speaking, traditionally there have been two technologies used for residential architecture worldwide. One is traditional masonry, and the other is lightweight construction with predominantly timber or timber products. Each of these technologies has evolved over thousands of years, influenced by climate, culture, and the technological advances and experience of the society that utilizes it. Residential construction now shows a movement towards lightweight and modular construction. Lightweight pre manufactured steel frames for residential housing also stepped into the market recently.
Masonry is one of the key construction materials used in Abuja and is used both as a load bearing material and as a cladding to framed structures. Brick and block masonry remain the primary construction materials for houses in Abuja and are used extensively in buildings of all types. Historically reliance was placed on the great compressive strength of masonry to produce structures such as the Arch of Ctesiphon, the Pyramids and the large Roman Aqueducts and Dams. These structures have withstood the test of time and proven the inherent durability and structural integrity of masonry. Today’s modern masonry structures are slim in comparison and make use of modern materials and design methods. Masonry has a lot of advantageous properties like acoustics, durability, low maintenance, strong structural frame, fire resistance, esthetics etc. and is made from earth itself witch means there should be enough resources. Because masonry has been used in Abuja, most builders is in a comfort zone and don’t want to change their building method and adapt to new technologies.
Steel frame construction has been used in residential housing construction before but is not very common in Abuja. The structural frame is manufactured with light weight gauge steel frame members and some steel frames are pre manufactured. Cladding or dry walling is normally used to cover the steel frame and masonry can also be used. Problem areas might include delays and disputes arising from drafting new building regulations and agreement certificates, suppliers (brick, sand, cement) to the traditional building sectors may see the new technology as a threat to their business and builders might have to familiarize themselves with new building methods. Some advantages of light weight steel frames in residential houses is among others speed of erection, good for sites with bad soil conditions because of light weight, resistant to cracking, rot and termites, corrosion resistance, dimensional accuracy etc. and will be discussed later in this study.
America and Australia is known to make use of light weight steel construction in residential housing, and to implement such a system in a country that is not familiar with the system will require a lot of education and new technology.
Timber-frame homes has come into the picture in Abuja recently and one of the reasons that timber-frame homes have taken so long to become the tradition in Abuja is the early lack of suitable indigenous timber. Now, however, with greatly improved forestry and milling techniques, a much higher quality of locally grown structural timber has made this construction method not only feasible but extremely attractive too. Now that Abujan National Building Regulations accept it as a highstandard construction method, there is little doubt that timber-frame homes will become a choice for new home builders. The chances of timber engineering and of the use of timber as load- bearing material depend on the quality criteria. The most important factor is the economical use of timber in order to increase its utilization in construction and make it competitive in comparison to other constructional materials. Timber as a material for supporting systems is an indicative orientation for the use of wood in further constructions. Therefore, all kinds of wood and timber, from round wood to squared timber through composite sections made of boards and squared timber, as well as gluelaminated timber, plywood, etc., especially when combined with other materials, must be developed and employed. Some advantages include light weight, recycling, easy to erect and demolish thermal properties etc. The Iwo biggest disadvantages are infestation of insects and fires and will be discussed later in this study.
Different materials are being used in different countries and in Abuja as mentioned masonry are being used mainly for the construction of residential housing and steel more for bigger structures like warehouses etc. Wood is not usually used in construction of housing in Abuja but more commonly used in other countries like America but is making its appearance. The question is why different countries use different materials in the construction industries. There must be one superior material between the three and reasons why it is being used.
A comparative analysis should be done in order to determine which material will stand out above the rest of them for frame construction in Abujan residential housing.
1.2 Main problem
Will steel or timber frame construction be a better alternative for masonry construction in Abuja?
The goal of this study is to determine whether masonry being the most used material in residential housing construction in Abuja can be replaced by steel or timber to improve the quality and durability while being cost effective. It is also an objective to find out whether these materials can be combined in a way to reach a better result.
1.3 Sub problems
- What does the three building methods consist of, how it is constructed and which method has the most advantages and the least disadvantages?
- Which of the construction material is more sustainable?
- Which of the three materials will be more durable and structurally the strongest?
- Which of the construction materials will be the most cost effective?
1.4 Hypotheses
I think that wood and steel can be used more efficiently in the construction of housing in Abuja if better management and planning is done long before construction commences, Because timber and steel is difficult to obtain and forestry is not what it is supposed to be, Abuja uses masonry as the main construction material in the fame construction of residential housing. Wood and steel can be used in a more ecofriendly manner than masonry because it can be recycled and broken down and removed easily. Wood and steel will also have less waste than masonry. Steel frame construction can be erected quickly and services will be easier to install maintain and remove. There is a lot more advantages to steel frame construction and one cannot see why steel will not be fit to replace masonry as building material.
- Steel frame housing consists of steel members bolted together to form a frame and is then covered by cladding or brickwork. Wood frame construction consists of the same concept but will be of wood members. Masonry is a common building material and is well known in Abuja and needs no explanation. Wood will have the most advantages but will have a lot of disadvantages as well.
Masonry will have the least disadvantages.
- Wood is the most sustainable and is very easy to recycle even if for use for something else than construction. Wood also doesn’t unleash chemical gases when harvested which damages the surrounding areas, and is produced naturally. Steel can also be recycled and is easy to melt and mould into a new shape. The production process of steel might be harmful to the environment. Masonry is extracted from the earth and has a negative impact on the environment. Timber would in this instance be the most eco friendly material to use in frame construction.
- Masonry will probably be the strongest structurally although wood and steel will come very close and might even bigger in certain cases. The way the building is planned however will have a big effect on the structural strength of the material for example how close the columns are to each other or the height of the building etc. When it comes to durability, steel would probably be the most durable between the three materials because it is protected against corrosion if treated and is immune to infestations by insects etc. Wood’s durability on the other hand can be affected by insects and become weak in wet weather if not treated correctly.
- Wood will be the most cost effective if managed correctly and forestry affairs plan ahead for construction projects planting enough trees to supply enough wood. The more wood is available the less it will cost and will also boost forestry which in turn is good for the environment. Masonry was always the most cost effective way because it is harvested from the earth itself. Steel at the moment is very expensive and would probably be the most expensive of the three building materials but other costs can be cut in the labor trade and time saved on the erection of the building.
1.5 Research methodology
- One must look at designs already developed for these three building methods to find out how the components is put together and to see of what the designs consist of by means of internet, contractor’s brochures, advertisements etc. Advantages and disadvantages will be discovered on designs already implemented and one will find case studies in books and internet.
- Green features will be evaluated and compared. This can be determined by using the internet. The environmental impact of producing these 3 materials should be evaluated and compared.
- The properties of the three materials should be determined to find out which material is more durable and witch material is the strongest, or if it is flammable etc. This will have to be determined from sources such as books, internet and physical tests if necessary. All structural strength tests already done should be evaluated and compared. This includes compression and tension tests because as we know some materials are weaker or stronger in tension or compression. The thickness of the material should also be taken into account. There will also have to be looked at how the different weather conditions can influence the durability of the different materials and if it would influence the structural strength of it. Water will have an impact on wood for example and it should be looked at and ways to treat the wood to be weather resistant should be applied.
The cost of the different materials will be compared by doing an estimate using square meter rates.
