Construction Structures Materials and Fire - Term Paper Example

Introduction “Construction involves the assembly, joining together and erection of various structures. Constructed structures serve various purposes just as they are of many types. There are storage facilities, work places, constructed shelters which man uses to adapt to his environment. Streets, subways, tunnels, high ways and bridges are structures used for travel.” Construction of structures is therefore very important since people cannot operate without these structures. They are either living, or working in constructed structures or traveling on them. The safety of human beings therefore depends a great deal on these structures. They should be made in a proper way that will guarantee the safety of all the people using them or even those doing the construction. The strength of the construction depends on its design and the materials used to make it. Materials used in constructions need to have a certain standard minimum level of strength depending on the purpose of the finished construction. For example storey buildings or bridges often have heavy weights placed on them. They therefore need strength coming from the materials used to make them in order to withstand this kind of stress which may result form normal activities or emergencies as in the case of accidents, attacks or natural disasters, Kibert (2008). Another important quality of materials used in constructions is that they should as fire resistant as possible. They should not be easy to catch fire and spread it. Instead they should be barrier to any spreading fire. Materials that are suit for use in constructions should have some characteristics such as the ones below. The material should not be easy to disintegrate when exposed to the heat of fire. These materials should have a stable structure and should not expand when temperature rises due to the fire. They should not contract too much from abrupt cooling when water is poured on them in the process of putting out the fire. The material should also not catch fire easily; Thompson, Sorvig (2007). “Construction normally leads to completion of structures.” There are several types of constructions such as industrial construction, civil construction and building construction. In architecture and civil engineering, construction deals with the assembly or the building of infrastructure. A project manager is assigned to manage the job while supervisory duties are done by either a design engineer, project architect or a construction manager. “In building construction, both small and big structures are added to land or real property.” Heavy construction better known as civil construction involves the addition of infrastructure to building environments. Industrial construction is done with design, planning and construction skills that are high in specialization, Kibert (2008). Methods of construction Architects and designers of today have a lot of pressure placed on them to come up with energy saving building constructions. Traditional construction methods have no guarantee of meeting future development demands. This calls for the promotion of modern or new methods to work along the old ones. Many people are discovering that is important to have both old and new methods all together. Old methods of construction have their own style while modern methods come with totally different things. They involve better processes and products. All construction methods seek to achieve a number of things in a building. These things are to protect the contents or occupants of the building from the weather, to hold its contents and itself up, continue holding itself up even in pressure from earthquakes and wind. Many functions may be achieved using one material or otherwise one function can also be achieved using different materials. It only depends on the type of the building. To reduce the volume of work on a construction, one material should be used for many purposes. However, this aim is normally hampered by the properties of materials such as heat resistance, strength and water resistance; Thompson Sorvig (2007). Stick Frame Many modern buildings are made in this manner. The building is constructed using several structural pieces called sticks. They are put together in order to get the total strength required. Wood or steel is used to make the ‘sticks.’ Stick framing gradually turns into ‘post and beam system’ when the ‘stick’ become bigger with bigger distances between the. The two methods can also be combined to achieve a better thing. “Stick frame construction is popular because the most common technique, platform framing, allows the use of many standardized pieces of wood and can be done relatively easily and rapidly.” The platform framing method has each of its floors made up in a totally different way from the other. The roof in only added to the top. In stick framing however, the pieces are made for holding the building up and no other purpose. They serve no other purpose like insulation, give protection from wind or rain. Other materials are brought in to take those functions. Stiffness to resist wind loads is achieved by use of ply wood or sheet good such as OSB. Some material to serve as an insulator is stuffed in between the 2 by 4s to resist the heat. A water proof material is now put on the whole of the exterior’ Thompson, Sorvig (2007). Older designs of stick framed buildings were constructed from 2 by 4s but modern buildings are being constructed with 2 by 6s. Advanced framing which is a modified method of framing or "optimum value engineering" is used in an attempt to get increased insulation and the use of less lumber. To achieve even more insulation on some buildings, double 2by 4s are used in various configurations but they require more labor and wood. In other buildings light gauge framing by use of steel is substituted with 2 by 4 in walls that don’t carry any load. This is achieved with the continually using ‘wood stick framing’ for the parts that bear pressure from loads or even going for a structure with beams and posts. Steel has a high recyclable capacity and most of its content is recycled. However it has a ‘cold bridging’ problem since it is an excellent heat conductor. To solve this problem an extra outside foam board insulation layer may be used or even a double wall instead of the insulation; Kibert (2008) Post and Beam and Timber Frame “A post and beam structure differs from a standard "stick frame" structure in that rather than using smaller size lumber like 2x4s or 2x6s spaced 16 or 24 inches apart, it uses more sizable lumber like 4x4s and 6x6s or larger spaced 4 feet or more apart.” Timber framing uses the posts and beams. No big difference can be found between traditional and current timber framing although the traditional one did not make use of nails. Post and beam method does not leave its lumber exposed as can be seen in timber framing. Post and beam and timber frame can be seen in many cob, light clay and strawbale buildings. Timber framing can be done together with SIPs; Thompson Sorvig (2007). Structural Insulated Panels (SIPs) SIP stands for Structural Insulated Panel otherwise called stress skin panel. In SIP there is a double layer of sheathing material most likely OSB covering foam insulating material most likely polystyrene on both sides. Each of these materials may not be strong when alone but the sandwich is very strong. If one skin bends the next one stretches because of the force. OSB may not resist bending but it cannot be stretched or pulled apart easily. SIPs are known to save on wood as opposed to stick framing. However, this depends on the details of the specific structure and the SIP system being used. The cost of stick framing and that of SIP framing are not very far off from each other. Although SIP needs expensive materials, the labor involved is not so much; Kibert (2008). ICFs The concrete forms have holes in them which are stuffed with concrete after being stacked together. They are insulated and resemble bricks. The forms insulate the walls but do not require a lot of concrete as the normal concrete walls. Many ICFs are made from new polystyrene although there is one product caleed Rastra which is made from recycled polystyrene. Other two products Faswall and Durisol are composed of wood chips in place of polystyrene; Thompson Sorvig (2007). References Kibert Charles (2008); Sustainable Construction; Green Building design and delivery Thompson William, Kim Sorvig (2007); Sustainable Landscape Construction; A guide to green building out doors. Read More