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B uilding materials have been playing an important role in the construction industry. They were all natural occurring in ancient times, e.g. stone, wood, straws, clay, lime, brick. (Taylor, 1985). As building technique was improved, simple composite materials, combined by means of mixing and/or heat treatment, were developed. A typical example is concrete, which was developed by the Roman Empire (Kong, 1998). Due to advance in science and technology at the beginning of the 20th century, materials with better performance and durability were introduced, e.g., reinforced concrete, steel, plastics and metal (Taylor, 1985). Some people argue that the need of building maintenance can be reduced by improvements in building materials. But is it really the case? In this essay, I am going to examine what governs material performance, its durability and building maintenance, as well as their relations.
B uilding maintenance is the process of checkup and correction of any defects in a building. The reason for the need of building maintenance is to ensure the building is in good condition. Any defects must be immediately remedied after building surveys have been completed; otherwise building failure results, which may cause injuries and deaths. As you know, a high-rise building generally consists of 30 storeys or above, which accommodate at least 2,000 people. Once the building collapses, the consequence is disastrous. Therefore, building maintenance is essential in all buildings and it should be taken at least once a year in order to find out the potential hazards as soon as possible.
A number of factors would affect the need of building maintenance, such as material performance, its durability, labour skill and construction technology. The performance of building materials depends on two factors: properties and uses. General properties in building materials include strength, mass, density, electrical properties, thermal properties, insulation, deformation, deterioration, durability, fire resistance, health, safety, appearance and cost. Apart from the general properties, there are specific ones for some particular materials, e.g., optical properties in glass and acoustic properties in sound absorbing materials (Everett, 1994). What is the significance of investigating the properties of building materials? It helps us understand the use of a certain building material for a particular design. Feld, who did comprehensive work on building failure analysis, said that ‘there is no ideal material?(Feld & Carper, 1997). Every material has its own advantage over the others in one aspect but it may fail in other aspects. If the material is used in an unsuitable place, its performance is greatly reduced, which could increase the need of building maintenance.
D urability is the second factor that affects the need of building maintenance. It is defined as the ability to resist weathering, chemical attack, abrasion or any other process of deterioration (ACI, 1982). Not only do strength, density, permeability, air entrainment, dimensional stability, characteristics and proportions of constituent materials, and construction quality affect the durability of materials (Feld & Carper, 1997) but the surrounding environment, such as temperature, humidity, sunlight exposure time, daily temperature range, rainfall, wind speed and direction, etc., is an important factor too (Ransom, 1987). The durability of a material is an essential element when its performance and uses are considered. The need of building maintenance can be reduced when building materials with better life span are used.
I n all construction projects, labour is always involved. They act as transformers, which change raw materials into final products, i.e. to mould the shapes of buildings. In this transformation process, human errors exist. There are mainly two kinds of human errors during a construction process: design errors and operational errors. Design errors occur when there is misunderstanding of design concept, deficient connection detail, calculation error, inappropriate selection of materials, failure to consider maintenance and durability, unexpected quality of work and miscommunication. Operational errors include alternations made to the structure of a building, change in use, operational judgement errors and negligent overloading (Fled & Carper, 1997). Some human errors can be avoided while some are inevitable. Because of this, the building cannot reach its best condition even the materials used are of good performance and durability. For example, if a worker is not skillful enough in handling a new building material, no matter how well its performance and durability are, the building constructed still cannot function in its maximum efficiency. Under this circumstance, the need of building maintenance is increased. Thus, the presence of human errors accounts for the requirement of building maintenance, despite how the materials perform and how durable they are.
C onstruction technology is another point for considering the need of building maintenance. In the past, since lifting of heavy materials to great height was very difficult, brickwork-like approach was used, i.e. small pieces of materials joining and staggering to each other to form large structures and components (Kong, 1998). Nowadays, with improvements in technology and skill, much labour-intensive work are replaced by easy-handled machines. In addition, the concept of system formwork, dimensionally coordinated components, mechanized construction, system/industrialized buildings, precast components, coordinated project information, etc., are introduced in the construction industry (Kong, 1998). With the application of machines, the precision and accuracy is increased. This new development greatly reduces the labour cost, errors in construction as well as the need of building maintenance.
S o, can the need of building maintenance be reduced when materials with better performance and durability are introduced?
A s stated, the performance and durability of materials, labour skill and construction technology are factors which influence the need of building maintenance. But as soon as the whole construction project is concerned, the most important matter that governs the need of building maintenance is neither the material nor the technology, instead, it is the labour skill. No matter how good are the materials, they cannot perform its best if human errors exist in the methods of applications. In order to reduce the need of building maintenance, all the factors -- material performance, its durability, labour skill and construction technology -- must be improved simultaneously. It is true that improvement in one or two aspects may reduce the need of building maintenance, but the risk of complete reliance on only one or two aspects is extremely high.
F rom the above arguments, I strongly support that with the development of materials with better performance and durability, it is not a must for the reduction of the need of building maintenance. The performance and durability of materials are the only two factors affecting the need of building maintenance. Unless all aspects mentioned above have improvement, the need of building maintenance cannot be drastically reduced.Reference:
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