Deconstruction And Methods Of Demolition Construction Essay

deconstruction And Methods Of death Construction Essay on that point be m some(prenominal) advantages of deconstruction over standard devastation. These advantages include (1) preservation of landfill space (2) makes recycling easier (3) potential expression materials available for re commit (4) carry on natural resources that would otherwise ingest to be use.In order to background the amount of natural resources being used and the energy involved in manufacturing these materials, a cautious approach to the disposal of CD unwarranted require to considered. Reusing materials prevents the use of embodied energy. This is the energy that goes into the production and manufacturing of a new product. bring down the amount of energy required in manufacturing, producing and transporting new products leads to a diminution in damage to the environment. The figure be belittled shows a system which could be implemented in order to do the up offer of materials being given over of on construction sites.Waste Management Hierarchy for construction and demolition transactionsChallenges facing deconstruction in that location atomic issue 18 a number of challenges which face deconstruction including (1) tools needed for deconstruction do not of all cartridge holder exist (2) disposal costs of CD muff is relatively low (3) deconstruction takes up more time than conventional demolition (4) build and design codes do not incessantly cover the reuse of build materials (5) edifices be not designed to be dismantled (6) the environmental and sparing advantages of deconstruction are not recognized.Deconstruction around the worldAustralia brashness of looseness producedThe total volume of waste produced in Australia almost double between 1997 and 2007. In 1997, the total volume of waste produced in Australia stood at 22.7 million tonnes while in 2007, the total volume of waste shot up to 43.8 million tonnes. While 29% of the total waste produced was flat from household waste, the CD sector accounted for almost 40%. (ABS, 2010)Demolition purposeThe NetherlandsWaste TaxWaste taxes are placed on waste brought to the landfill or to the incinerator. The rate of tax drive away vary depending on the case of waste. In 1995, the Netherlands imposed a tax on the disposal of waste. The origin for this tax was to make other forms of waste intercession more appealing. Since the institution of the tax the total volume of waste sent to landfills has decreased by a signifi slewt amount. The figure below shows how the huge decline in waste sent to landfills since the tax was imposed in 1995. (Oosterhuis et al, 2009)This landfill tax is always on the increase in the Netherlands. In 2009, the landfill tax was 90 per to ane. This is unmatched of the spicyest landfill tax rates in the European Union. (defra.gov.uk, 2010)Waste production and treatment in the NetherlandsLandfill Waste BanAlong with imposing waste taxes, the Netherlands likewise implem ented bans on sending recyclable and combustible waste to the landfill. This came into operation in 1997. This included separated CD waste. The reason for this ban was to limit the amount of waste going to landfills which is seen as the least favoured method of disposal. The business for implementing the ban lies with the landfill operators who are inspected fixturely by the governments waste management agency, SenterNovern. The introduction of the ban in the Netherlands proved to be a success in acid down the amount of CD waste sent to landfill. In 2009, 97% of CD waste in the Netherlands is recovered. (defra.gov.uk)Deconstruction ProcedureStep 1The first step in pull down a building is to check to see if the building contains any waste substances. One of the principal(prenominal) hazardous wastes which cause concern in Ireland is asbestos. This is a natural mineral which is used in many buildings for fire proofing or thermal insulation. The danger with asbestos is that if it breaks up, the fibres which make up asbestos whitethorn wherefore be inhaled into the lungs as dust. This increases the risk of lung notifycer and causes lung tissue scarring. Under EU principle it is no longer allowable to re-use asbestos or to even buy products containing asbestos in Ireland. This means that asbestos cannot be recycled it essential be disposed of after it has been take away from the building. (citizensinformation.ie)Step 2After a specialist contractor strips the building of all hazardous materials it is time to investigate the building and salvage any objects that can be reused as they are. This may include marble fireplaces, tint floors, radiators, doors, sinks and central heating boilers.Step 3The building is categorised on a lower floor one of the following three headingsBrick turn over or block work buildings with calibre floors and tonicity roof anatomical social organization with roof tiles.Concrete frame buildings with prestressed cover circum stancess. mark frame buildings.Step 4For all three categories above, the succeeding(a) step is to remove the flooring, tiles, plaster from the walls and ceiling. Windows are removed along with service installations (e.g. wall plugs, light switches). Metals are then removed and piping is likewise removed before the proper demoltion of the building starts.Step 5thither are a number of different types of waste that arise from denudation the building. These should be then split up into burnable and non-burnable materials. The burnable components brought to be incinerated while the non-burnables brought to the landfill.Step 6DemolitionBrickwork or block work buildings with timber floors and timber roof structure with roof tiles.When every component of the building has been removed with the exception of the masonry works and the floors it is time to start pickings the building apart floor by floor. Floor joists and timber floors are removed using a crane. These timber joists and floori ng can then be reused. The advantage to using these second hand joists and flooring is that they are fully seasoned meaning they will not shrink.After the timber has been removed, the masonry blockwork is cut into sections and transported to be crushed. It may also be the case that the blockwork may be needed by the owner of the building in a new construction project. In this case the blocks are pulled down one by one and the mortar removed.Concrete frame buildings with prestressed cover components.Prestressed concrete components in a building cause problems when it comes to disassembly because most of the time it is not known that the elements are actually prestressed. If prestessed concrete is cut up it may cause a structural element in the buiding to collapse.Steel frame buildings.The beams are dismantled one by one on the job(p) from the top down. If the steel beams cannot be reused then they are cut and to be melted and remouilded. From time to time, steel structures like bri dges are merely partially taken apart and shipped overseas where the exact bridge is reused in another location.Step 7The foundations of the building are th final step in the deconstruction of a building. Like the other elements of the structure the foundation is separated, disquieted up and transported to the crusher. In the case of concrete piles, they are removed by vibrating and pulling. If it is the case that wooden piles have been used as the foundation then it may be more unmanageable to remove as it will tend to break into pieves when being pulled from the ground.Demolition TechniquesBallingThis is the demolition technique where a heavy cast iron or steel ball is used to knock a building. The ball normally weighs between 500 to 5000kg. The balling technique can be used to put down concrete, reinforced conrete and masonry. It has become less popular due to the level of preventative which arises on site including vibrations, noise and dust.The ball can come into affaire with the building in two ways (1) free fall (2) swinging. In the free fall process the demolition ball is lifted up into the air by a large magnet and then it is dropped onto the building which is to be demolished. In the swinging process the demolition ball is affiliated to a steel line which is attached to a auto with a rotating frame.Demolition Ball at workDemolition ledgemans in that location are two types of breakers used in demolition (1) pneumatic (2) hydraulic. The difference between the two is pneumatic breakers are happen using compressed air while hydraulic breakers use compressed oil. These type of breakers are used on concrete, brickwork and stone. both types of breakers are mainly associated with minor demolition works, however they can also be attached to excavators for major demolition works.Pneumatic circuit breakerhydraulic ShearsHydraulic shears are attached to excavators. They can be used in the demolition of any size structures and a wide range of materials like steel, concrete and timber. The two shears have toothed shears which slide past eachother to break up the selected material.Hydraulic Shears sensitive steelThermal CuttingThermal cutting is used to cut steel and iron. Cutting torches are used for this process. There are three types of cutting torches (1) provide/oxygen (2) pulverisation (3) plasma. The fuel/oxygen cutting torches are run on a crew of oxegen and fuels such as natural gas, propane and acetylene which cuts at a maximal temperature of 3200 degrees Celsius. The choice of the fuel depends on the succinctness of the metal.If the metal is too thick for a regular cutting torch then a pulverise cutting torch can be used. These can reach a maximum temperature of 4500 degrees Celsius. The powder cutting torch is more expensive than the regular cutting torches because there is an extra fed in the torch which allows atomic number 13 and iron powder to be supplied. This is what increases the temperature of the flame.T he plasma cutting is run by supplying electrical energy to gases such as helium and argon. These are used to cut alloyed steel which can be a slow process using the other two methods. Plasma cutting torches can cut up to four time faster than powder cuttinf torches.ExplosivesExplosives can be used in the demolition of buildings. Explosives can be set of using a wide variety of detonators which allows different burst speeds. Explosions can be set off immediately or can be delayed by milliseconds if required. By blast certain components of the building before others, it will allow the collapse of the structure to be carried out in a controlled manner. Even though this may help in accurately collapsing the building, there are still numerous examples of demolitions that have kaput(p) wrong when explosives have been used. This is why a large area moldiness be cordoned off around the demolition site before blasting takes place.Crushing Separating CD WasteImmediately after a structure has been demolished it is transported a treatment plant where crushing and separating takes place. This enables new materials to be produced. The CD waste must go through a number of processes before it is recycled. It must get sieved, pre crushed to prevent the lager materials from disconfirming the main crusher and all material such as steel, glass, plastics and timber must be removed manually, by air separation or by washing. The materials must then be sieved at the end of the process in order to get the requied sizing for the new material. consult CrusherThe jaw crusher is the machine use to pre-crush the CD waste. Large components such as reinforced concrete can be fed directly into the toggle crusher and are broken down into smaller piece by the moving jaw plate.Jaw CrusherCone BreakerThis type of machine cannot deal with large CD waste. After the waste has been pre-crushed the cone breaker is used as the main crusher. Inside this crushing machine is a cone that moves at high speed crushing waste material against fixed plates.Cone Breaker