The Use of Timber Frame with Concrete Frame in Construction - Assignment Example

CONSTRUCTION MATERIALS By Student’s name Course code and name Professor’s name University name City, State Date of submission Question 1: Compare and contrast the use of timber frame with concrete frame in construction. The art of timber frame construction has evolved over time to being a turning point in the history of structural building and design. This methodology emerged at around 500BC during the construction of the New Greek Temple that was as a result of the newly discovered tools i.e. the broadaxe and the adze that made it possible for artisans to produce and shape large quantities of timber within a short period of time. This has been since been followed by a series of developments that are aimed towards efficiency in producing high performance timber frames whose main feature is high strength. According to Benson and Gruber (1995), there has been a considerable change of the above achievement in that timber is eventually losing its domination for other methodologies such as concrete frame construction. In a bid to beat its competitors, timber structures have been standardized to ensure that the parts are prefabricated in time for assembly. Concrete frame construction has been a close competitor to timber frame construction since its inception. This methodology borrows a lot from the timber frame construction apart from the fact that it mainly makes use of concrete and steel bonded to form a unit. In building spanning structures, the use of beams and slabs has been hailed due to the superior strength capabilities that come with this methodology. The concrete frame skeletal concept is also likened to timber frame owing to the similarities in their structural composition. Stabilization is achieved through intertwining of beams and columns as the fundamental elements in concrete frame construction. Preformed structural connections also exist between the beams and slabs for the purpose of time saving in projects that utilize this methodology to come up with various structures of this nature (Bryan, 2010). Selection of method for application in coming up with a given structure entirely depends on the existing choices for the same. While considering a method of choice, it is worth for a contractor to go through the pros and cons that are attached to these methodologies. Ideally, there is no one method of construction that is preferable over the other since it all depends on the project requirements and the preference of the self builder. Speed of building is however one critical issue that should be considered for the sake of project delivery (Owen, 2013). The emerging concept of prefabricated timber frame has quickly revolutionized the craft of timber frame construction. Based on the standardization process that has been developed over time, it is now possible to deliver ready made parts for boxing and assembly into a final product. Concrete frame however has a long way to go in order to achieve the admirable progress that has been seen in timber. Another point about speed is the fact that timber frame construction cannot be marred at all by the weather which makes it a preferred. In a matter of days a frame made of timber can be erected without due consideration curing processes that are considered in concrete frame construction (Owen, 2013). The ease and quality of construction has also attracted many structural contractors and home owners towards timber frame construction. Coming up with the framework is relatively easy since the prefabrication of materials is usually carried out in a controlled environment. Due to accuracy the constructors do not necessarily need past experience in coming up with this type of constructions. On the other side it is very necessary that a person undertaking the structural design or the masonry for the sake of concrete frame construction be direly trained for this purpose. Experience is also mandatory for the purpose of accuracy and achievement of high level construction standards (Owen, 2013). Thermal performance of timber frame construction outdoes that of concrete frame construction since timber is a natural insulator. This advantage translates to structural efficiency in that the wall thickness required for timber structures is absolutely thinner than that of concrete frame buildings. The act of sealing timber frame buildings for the purpose of insulation has been found to provide superior thermal performance capabilities. This can be noted during the winters when the temperatures are low and warmth has to be maintained for a habitable environment. When it comes to noise and sound insulation, it has been established that timber possesses a high level of noise reduction properties. This is achieved through the use of double walls within the structure that is being built in order for the void space to act as an insulation blanket. This has also been observed in high performance areas like playrooms or bathrooms that require high noise reduction functionality (Allen and Iano, 2009). The load bearing capacity of the concrete has been found to be considerably higher than that of timber frame buildings. On the other side, within its own calibre as a construction material timber is a strong based on the design methodology that is used when coming up with a workable prefab in readiness for production. Timber is considered as a durable material unless calamities such as fire strike in unsecured times. When it comes fire timber cannot extremely withstand the heat and can even crumble down within a very short period of time. This in comparison to concrete frame construction which withstands the flame, there is a chance to salvage the framework unless conditions are extreme to an extent whereby the strength is lost (Owen, 2013). The cost factor of this construction methodology is difficult to come up with in as much as this information is readily available from the experienced practitioners. The comparison in terms of materials is however not consistent as expected since the percentage variance is very small. Most of the contractors usually specialise in one kind of material making it difficult for one to actually find an architect who can effectively do construction by employing both timber and concrete frame building. In one instance, timber frames that are sourced in their prefabricated forms have been termed as expensive in comparison to their raw counterparts. The speed at which a structure is built also affected the pricing which makes timber frame construction in other areas expensive than concrete frame construction. The prestige also shifts from one point to the other with the most preferred method fetching the best price in a given location. There is a price contradiction in most of the timber frame construction unlike the concrete frame which does not consist of many accessories (Emori and Schnobrich, 2011). Question 2: Material Hygroscopy a) Percentage of moisture in timber Initial weight = 3.27kg Weight after immersion = 3.87kg Moisture content = 3.87 – 3.27 = 0.60kg Percentage moisture content after immersion = 1 = 18.35% b) Hygroscopic material definition A hygroscopic material is considered as a material that is capable of adsorbing or absorbing water molecules from the relative humidity or moisture within the dominating environment. This occurs when the macro and microcapillaries exert pressure on vapour thereby creating a difference that is worth being eliminated. In such cases whereby the moisture content of the hygroscopic material supersedes that of the environment, then the unbound water renders the material non-hygroscopic until the material is dried. Such is the case of timber which must be imposed on heat conditions to make it dry but also renders it hygroscopic (Kudra and Strumillo, 1998). c) Explanation on why timber for internal utilization requires a specific moisture content Seasoning of timber differs in degree from one location to the other depending on the moisture levels of the environment. Each environment is considered to have a specific content of moisture and this is the main factor that is considered when deciding on the allowable moisture content to which timber should be seasoned. This is done as an approximation of the actual environmental moisture in order to maintain the equilibrium conditions for purposes of stability. This also makes the material non-hygroscopic in order to eliminate such defects as dry rot and attacks from fungi (Australian Hardwood Network, 2013). d) Visual and Olfactory Signs of Dry Rot Visual Signs Shrinkage Crumbing Splitting Mycelium Pancake like growth can be observed at the middle of the timber Olfactory Sign Mushroom like smell Prevention This problem can be prevented by ensuring that all plumbing leaks within a building are eradicated. On a higher notch, timber should be well treated prior to usage in order to ensure that high moisture is reduced even as it comes to material screening and choice. Borate fungicides should also be applied in ensuring that this problem does not spread to other sections of the structure as a way of preservation (Rajput, 2005). Question 3 a) Sieve Analysis SIEVE SIZE (MM) MASS (G) % ON SIEVE % PASSING 125 0 0 100 75 0 0 100 63 88 6.29 93.71 37.5 55 3.93 96.07 20 87 6.21 93.79 10 98 7.00 93.00 6.3 95 6.79 93.21 3.35 102 7.29 92.71 2 129 9.21 90.79 1.18 89 6.36 93.64 0.6 85 6.07 93.93 0.3 90 6.43 93.57 0.212 92 6.57 93.43 0.15 84 6.00 94.00 0.063 90 6.43 93.57 Table: Sieve analysis b) Sieve analysis graphs Graph 1: Particle size distribution. Graph 2: Particle size distribution for initial sample. c) Explanation The particle sizes that were being used were of different sizes in terms of extremities. It is utterly observable that the material that is being used passed the sieve fully at 75mm which means that the soil being used had a certain amount of large clods. This is further indicated in the graph which is irregular unlike the initial sample which had a lot of uniformity thereby giving a continuous graph. Works Cited Allen, E. and Iano, J. (2009) Fundamentals of Building Construction: Materials and Methods, New Jersey: John Wiley & Sons. Australian Hardwood Network (2013) Managing moisture, [Online], Available: http://www.hardwood.timber.net.au/specifiers/basics%284%29.htm [4 January 2014]. Benson, T. and Gruber, J. (1995) Building the Timber Frame House: The Revival of a Forgotten Craft, New York: Simon and Schuster. Bryan, T. (2010) Construction Technology: Analysis and Choice, Oxford: John Wiley & Sons. Emori, K. and Schnobrich, W.C. (2011) Analysis of reinforced concrete frame-wall structures for strong motion earthquakes, California: University of Illinois at Urbana-Champaign. Kudra, T. and Strumillo, C. (1998) Thermal Processing of Bio-Materials, Amsterdam: CRC Press. Owen, J. (2013) Pros & Cons of Timber Frame Buildings, [Online], Available: http://www.constructionchat.co.uk/articles/timber-frame-buildings/ [04 January 2014]. Rajput, R.K. (2005) Comprehensive Workshop Practice, New Delhi: Firewall Media. Read More