Tower Bridge London - Admission/Application Essay Example

Tower Bridge London Bridges are structures constructed along two points in order to avoid rivers or canyons. A lot of skills which include a considerable level of architectural technology are required to come up with durable and strong structures. Many a time’s, construction of bridges relies entirely on the length of the bridge and the topography of land on which they are to be constructed. Long bridges are more susceptible to collapsing; therefore, they require accuracy and application of a suitable expertise together with appropriate tools and materials. Town Bridge is a combined bascule and a suspension bridge located in England’s London city. It was constructed for a period of eight years that is, from 1886 to 1894, along river Thames. The bridge is close to the tower of London from where its name was derived. Among its components are two towers at its upper level by two walkways, designed to endure the horizontal weights exerted by the hanging sections of the bridge. The vertical component of the weights in the suspended sections and the vertical reactions of the two walkways are carried by the two strong towers. By the end of the ninetieth century, London had grown so much with the population of Londoners increasing radically, but still motorists and pedestrians were restricted to use of a single bridge called the London Bridge, which would be used to move in and out of the city. Traffic jams became unbearable and with great expectation, the Londoners waited for the completion of the New Bridge which had been initiated by Sir Horace Jones, the City Architect and Sir John Wolfe Barry, who devised the idea of a bascule bridge with two towers built on piers. The construction took place at the time of steel revolution when made structures made of steel had taken centre stage in the human civilization. Size The bridge is estimated to be 800 feet (244 meters) in long with two towers of which each are 213 feet (65 meters) in height, built on piers. The central span of about 200 feet (61 meters) between the towers is divided into two equal bascules, which possibly can be elevated to an angle of 83 degrees to enable river traffic to pass. The bascules, approximately weigh 1,000 tonnes each are counterbalanced to minimise the effort needed for faster raising within a short time span (Speaker-Yuan, p98). Initially, high levels open walkways which were created a between the two towers were given a dull reputation. They were termed as hideouts for prostitutes and pickpockets. This made them to be rarely used and sometimes not to be used by pedestrians at all due to fear until their closure. After several years; in 1982 they were re-opened as a result of an exhibition which is currently housed in the bridge towers. As a result pedestrians have embraced the use of the walkways and this has eased movements in and out of the city. The bridge is currently used by over 40 thousand people including motorists, cyclist and pedestrians. Measures have also been put in place order to maintain the effectiveness of the historic structure. Among them are 20 miles per hour speed restriction and about 18 load limits. Gadgets have also been installed to warn and send a fixed penalty to drivers who break these rules. Refurbishment Announcement were made in April 2008 that the bridge towers would undergo refurbishment which would run at a cost of 4 million sterling pounds and for a period of four years. The scope of work involved scraping off the old paints and repainting in blue and white. Scaffolds were erected together with plastic sheets which would prevent the scrapped paints from falling into the river thereby causing pollution. Renovation was completed in mid 2009. Modern lighting systems were installed and they were meant to be used by both motorists and pedestrians and during the subsequent exhibitions. Generally the facelift was done in order to meet the required standards of bridge construction in accordance to the Design Manual for Roads and Bridges (DMRB). Civilization that built the tower bridge Report on how the tower bridge was built Tower Bridge was a project started by sir Jones Horace together with a famous engineer John wolfe Barry, who was very instrumental in coming up with the bascule design. It was designed in such a way that ships sailed through, meaning, it had walkways high above where pedestrians crossed above while ships passed below. Sadly enough Sir Jones never had the chance to walk through his own creation as he , passed on in 1887 before the prior to the foundations being completed and John wolfe oversaw the construction of the bridge after Jones death. Scope of work Construction work commenced on 22nd April 1886. Foundation was dug below the surface to about 10 meters below the water surface then it was built. This whole process was to prepare the river bed for the building of the piers which was done by divers who were employed to do so. Since the job looked scary, they had to use Scruba gears, safety devices and computer equipment. They also wore lather suits together with metal helmets and got connected to the surface of the water by means of air tubes. Cassions which are open ended water tight boxes with sharp edges were then built. They were lowered into the river till could rest on the river bed from where they were dipped into the firm clay by the divers to a depth of 9 meters. The water tight soil was capable of comfortably supporting the huge weight of the tower. Building the towers William Arrol and a company based in Scotland made steel for the towers. He then sailed to London to make the delivery. However, there was limited space which could be used to store all the steel needed for the construction at once, so steel was brought in bits especially the much needed at given stage of the construction. On the other hand, millions of rivets for the bridge were to be made and workers could only make 200 per day. This lengthened the construction period but after some considerable work, steel could be seen standing on river Thames like a huge skeleton, each tower with four pillars, two on the land side supported the suspension chains while those on the river side supported high level walkways. Building the walkways Walkways were built immediately the building of the pillars was completed. They were build 46 meters high above the river level and this would allow the boats to go through even without safety nets while the construction was still in progress. Workers were paid an averagely amount of ?2 per week. Cantilevers sections supported at one end which can withstand its own weight had to be constructed broadening from each tower, had to be constructed. Therefore separate workers had to be employed in order to increase the pace of work. Building of the chains and bascules Suspension chains and bascules made the use of the tower Bridge fascinating especially for ships. The chains were constructed by aid of scaffolds. Due to their heavy weight, workers built abutmetments on each end of the tower Bridge. An abutment is structure built suspension chains. Girders were added to reinforce the chains in order to prevent them from swinging during the strong winds. The bascules which acted as the arms of the tower would raise and lower to allow ships to go through. They were also reinforced with girders. A counterbalance which balanced the bascules was also constructed. This was because the bascules had a lot of weight which needed to be balanced. On the counterbalance was fitted with gears which coincided with the steam engines. These engines turned opening for the ships when their engine pressure rose. After eight years of work the tower bridge was finally completed. The bridge was officially opened on 30th June 1894 by the Prince and Princess of Wales with steamships and ferries parked along in anticipation River Thames. The prince through an official declaration opened it for traffic by pushing a button that raised the bascules during the ceremony. The following are the facts regarding the bridge It is the only movable bridge structure of all \the over two dozen bridges on River Thames. At the time of opening in 1894 it was raised and lowered a thousand times annually but at present, because few ships travel along the river it only opens 100 times in a year Materials used in construction Like other bridges most of the materials used in construction were steel and concrete. The bridge was long therefore much stronger steel was used to reinforce concrete. The steel used was manufactured in Scotland by William Arrol. The bridge was mainly made of steel. As can be observed in the picture below Oblique view of the tower bridge List brick machine used during The Blue Range The machine is hydraulically controlled with a pallet size of 1400x1500. It also has a number of concrete mixing plants and a pallet management system to select from and is labour efficient. The Yellow Range Fully operates by use of a hydraulic system with automatic control. Suitable fo various sizes of block making operations from medium to large blocks. It is a perfect example of a machine that can be used in large construction sites and for business expansions that requires high yields to meet sales demands.   The Single & Double Green Range This designed for a serious medium sized operation and can be used in heavy construction machine which operate hydraulically. It‘s easily portable compared to other machines discussed here. Yields are of high quality and mix designs can be of range 12:1 to 14:1. Can be operated even by those who are unskilled therefore it is easy to use Labour force at that time Five major contractors and 432 construction workers were involved in the construction process of the tower bridge. Even though the work was tedious, they managed to do it within a time span of 8years. The workers were also faced with various challenges that included ferrying of the materials all the time due to limited space that was on the site. Navigating the river Thames was not easy especially during foundation building process. A lot of expenses had to be incurred since sophisticated equipment had to be used like the use of air tubes. Workers were paid two sterling pounds which was higher that the wages of policemen. Today no big difference would be expected in a construction of such a huge and a strong structure whose construction paid much attention to the requirements of bridge building which is in accordance with the DMRB specification. When undertaking construction of structure in the current world much emphasis is given to emerging issues like global warming, infernos and much application of hi-tech designs technology. Global warming All over the world global warming has affected almost all the sectors that one may consider to be part of the economy. Global warming is as a result of much heat which collects in the atmosphere and causes the green house effect. In bridge construction much heat may lead to disintegration of concrete due to regular expansion and contraction if the steel concrete ratio is not checked properly. In the modern world it would be advisable to use steel and only use concrete at the foundation level. During the time when the tower bridge was being constructed, much emphasis was given to structural support and to some extent, beauty. Many People were still new when it comes to bringing up structures like this so all their focus was on one thing structural support and nothing more. With time construction industry had to undergo radical changes due to frequent fires and other environmental factors. Fire as one of the issues which needed to be addressed has of late left a lot of doubt whether concrete is sufficient material in building industry. However it may not be a likely scenario in bridge construction but i would apply hi-tech techniques which aim to minimize spread of fire in case of an inferno. Hi-tech building design refers to architectural designs services that involve the use of advanced technology thereby improving the function of the final product. It entail use of highly sophisticated materials like steel as the major materials and others like glass for beauty I would recommend full application of Hi-tech techniques since steel used in many parts of the world has help to curb losses which result from earthquakes which is now engulfing the world. Earth quake weakens concrete used in building since concrete is a brittle material. Hi-tech techniques have been applied in construction of prominent structure world over like the Olympic stadium in china among others that are regarded as the strongest structure world over. Work cited Speaker-Yuan, Margaret. The London Tower Bridge. San Diego, Calif: Blackbirch Press, 2004. Print. Read More