Saturday, November 30, 2019
The Great Bridge the Construction of the Brooklyn Bridge Essay Example
The Great Bridge: the Construction of the Brooklyn Bridge Paper THE GREAT BRIDGE: THE CONSTRUCTION OF THE BROOKLYN BRIDGE AN NTCP ANALYSIS OF THE BROOKLYN BRIDGE PROJECT EM ââ¬â 612 B Group D Luigi Ballarinni David DeBorja Matthew Gelmetti Jonathon Lum? TABLE OF CONTENTS 1. Executive Summary3 2. Background4 3. Statement of Problem5 4. Project NTCP Analysis7 5. Project Approach11 6. Conclusion16 7. References19 ? EXECUTIVE SUMMARY The goal of the Brooklyn Bridge was to allow people to cross the East River without waiting for a ferry, which at the time was the only way to travel to from Brooklyn to Manhattan. The new bridge would allow people to walk, ride a carriage, and even ride the rail, so people and goods could easily travel from one side to the other. This project made groundbreaking revelations; this included using engineering techniques which had not been used in the type of scale to their extent. Two types of engineering practices were the use of caissons for the foundation and a suspension bridge system, both of which had been limited in use before the Brooklyn Bridge. The way in which Roebling approached the Brooklyn Bridge was a critical component of the management project; he had a vision in mind before being granted the project and executed the project according to his elaborate plan. Although the construction of the Brooklyn Bridge was incredibly successful, the approach taken had left the very little room for error for the designers. Much of the success lies in the fact that the Roeblings had gotten most of the characterization correct. However, without any contingencies, the plan lacked much flexibility to adjust to any major setbacks to the project. We will write a custom essay sample on The Great Bridge: the Construction of the Brooklyn Bridge specifically for you for only $16.38 $13.9/page Order now We will write a custom essay sample on The Great Bridge: the Construction of the Brooklyn Bridge specifically for you FOR ONLY $16.38 $13.9/page Hire Writer We will write a custom essay sample on The Great Bridge: the Construction of the Brooklyn Bridge specifically for you FOR ONLY $16.38 $13.9/page Hire Writer The Brooklyn Bridge has progressed history in more ways than just one: even though it was one of the greatest marvels of the 19th century, it seems to have driven us to now always push the limits of engineering to its physical bounds and even past them. The following NTCP chart displays the categorization of the project, and the approach that the Roeblings had taken (shown in red): ? BACKGROUND In the early 1800ââ¬â¢s, Brooklyn and New York (Manhattan) were considered two separate cities. Even though they were just separated by a mile of water, the amount of trade which could be done between the two cities was severely limited. Their location along the eastern seaboard and the accessibility of their ports through the East River, made these two cities among the most prosperous in the United States. The East River prevented the two cities from utilizing the advantage of their proximity to each other. This was mostly due to the fact that the most common route from Brooklyn to New York was to take a ferry across the East River. Many problems were arising from the situation of only having ferries to get across the East River. This was resulting in long queues, overcrowded waterways, and dangerous conditions among others. In particular, the long queues seemed to be the largest problem; just one mile of water was stopping people from transporting anything whether it be their car or their time perishable cargo across to New York or Brooklyn. To have another way across, would allow for people to cross the East River without waiting as long. Business for these merchants would be easier with a method to cross the East River that did not involve ferries. It was often said that taking a train to Albany was faster and easier than trying to cross the river. The detrimental effects of not having any way across the East River except for the ferry climaxed in the winter of 1866-1867. Being that this was an extremely cold winter, much of the East River had frozen over leaving most traffic between New York and Brooklyn at a standstill because the ferries were not able to get across. This prompted the New York Bridge company to charter a project which would allow people to get from one city to the other in a time effective method that was not by ferry. They eventually decided to pick a chief engineer, John A. Roebling, who was famous for his wire rope suspension bridges.? STATEMENT OF PROBLEM The impending plans for the Brooklyn Bridge were seemingly daunting for its day and age. For one, it stood to become the longest bridge in the world, reaching over 50% longer than any bridge before it. The Brooklyn Bridge was also set to be built on the East River, one of the busiest waterways in the world. These were just some of the many issues that lay ahead of the construction of the Brooklyn Bridge. The first problem that was to be encountered by the designers of the bridge was the East River itself. The East River, unlike the name suggests is not so much a river, but more like a salt water estuary. This meant that unlike a river, the East River faced tidal conditions similar to most bodies of water connected to the ocean; these tidal conditions also contributed to the high levels of turbulence that existed in the waters. The East River also had not been fully explored to its depths. The sandy bottom prevented the designers from knowing how deep they would need to dig to reach ground solid enough to build a foundation to hold up the massive structures required for the bridge. The East River was also one of the busiest waterways in the world. This was the waterway that provided the lifeblood of two the busiest commercial ports in the world. Because of the traffic that would flow through the East River, any bridge that would span it, would need to ensure that the span reached high enough to avoid even the tallest sails of the largest ships. In fact, the legislation that authorized the construction of the bridge stipulated that the bridge must not ââ¬Å"obstruct, impair, or injuriously modifyâ⬠the navigation of the river. Finally, we have to consider the bridge itself. The impending Brooklyn Bridge would easily surpass all existing bridges in terms of length. With the requirement of the bridge not impairing water traffic, the bridge span must be much higher than many other bridges. Building a bridge of this length and height would require the use of a suspension bridge architecture. However, at the time, the suspension bridge concept was a relatively new architecture and had never been tested on a large scale. This architecture also would require two towers to support the structure and would require the construction of a foundation deep beneath the East River, using caissons. Caissons have been used to build structures underwater, however many of the uses were on a much smaller scale, and in much shallower waters. The design and construction of the Brooklyn Bridge obviously faced enormous hurdles and public skepticism before it was to be completed, therefore the proper design and approach must be taken in order to ensure the bridge is constructed successfully. PROJECT NTCP ANALYSIS In order to understand how the Roeblingsââ¬â¢ approach fit the project, we must first analyze the project on its own merit. Because of the enormously complex task at hand, it would help to have an organized method to analyze the project, therefore an NTCP analysis was performed on the project. An NTCP analysis is a technique used to characterize projects. This characterization is formed from a basis of 4 key criteria, which form the anagram that the analysis is named after. While many projects may have inherent differences depending on the objective of the task, the resources available, and the complexity of the project; by analyzing a project using the NTCP technique, a project manager may find that many similarities do exist between projects which are seemingly unrelated. By analyzing projects with similar NTCP profiles we can find that many of the projects encounter the same types of problems and require a similar managerial approach. The first component of the NTCP analysis is Novelty. Novelty is used to describe the relative familiarity of the product to the developers and customers. Novelty is broken into three main categories, labeled: Derivative, Platform, and Breakthrough. Derivative projects are defined by projects that extend or improve existing products, such as a next year iteration of an existing project. Platform projects create a new generation or significant improvement over existing products, such as the development of a new aircraft. Breakthrough projects introduce never before seen products or new to the world products, such as the creation of the computer. The Brooklyn Bridge project introduced a number of new breakthroughs in construction technology that influence the industry even to this day. Considered by many to be one of the greatest engineering feats of the 19th century and a marvel of construction, the Brooklyn Bridge ushered in the era of the modern-day suspension bridge. This bridge created a new concept that introduced the framework for building the modern-day suspension bridge, capable of crossing incredible distances. However, for all the incredible accomplishments and breakthroughs, it was still a bridge, and designers and builders have built bridges before, and therefore have some experience and familiarity with the project. Based on this, we can classify this project as a Platform project. Technology is the second component, which makes the T of the NTCP analysis. The four categories that make up the Technology component are: Low Tech, Medium Tech, High Tech, and Ultra-High Tech. Low Tech projects involve the use of existing, well established technologies. Medium Tech projects use many existing technologies with a few new developments. High Tech projects use many new or recently developed technologies, and possibly a few new technologies. Ultra-High Tech projects generally must develop new technologies as the basic technologies do not yet exist to accomplish the task. The Brooklyn Bridge project had accomplished a number of technological breakthroughs by the time of its completion. One such development was the use of caissons. This was not the first ever use of caissons, in fact caissons had been in use for at least a generation, originating in Europe. The most advanced use of caissons at the time had been the Royal Albert bridge, where Brunel had lowered a caisson over 70 feet to build the foundation for the railroad bridge. However, John Roeblingââ¬â¢s plan for the caissons were much larger than anything previously done, and were going to be dropped at least 30 feet deeper than the caissons used in Brunelââ¬â¢s project. The use of steel as a construction material was also a major technological development, as projects mainly used Iron at the time. The suspension bridge itself was a technological achievement as the bridge pushed the limits of construction and architecture; at the time of completion, the towers that support the bridge were the tallest free-standing structure in North America. While there was a significant number of breakthroughs for the Brooklyn Bridge project, the project still relied on many tried and true techniques, which would make this project a High Tech project. Figure 1: The design plan for one of the supporting towers for the bridge Complexity makes up the C component of the NTCP analysis. Complexity is a difficult category to encapsulate, as scale alone cannot completely determine the complexity of a project. ââ¬Å"A very large, and expensive project in one industry say construction might be less complex than a smaller project in another industry, such as biotechnologyâ⬠(reinventing PM, p102). Therefore we have to base complexity on a number of factors such as cost, scale, number of functions and components, and complexity of the organization and relationships between components. Complexity can also be related to the complexity of both the product and the process used to develop the product. The three categories that compose the complexity of a project are: Assembly, System, and Array. Assembly projects are composed of a collection of components that combine to form a single unit with a single function of a limited scale. System projects are a complex collection of components and subsystems, which can perform multiple functions. Array products are comprised of a wide collection of systems or networks which work together to achieve a common objective. The Brooklyn Bridge project contained a number of components which in themselves can be considered systems or subsystems. The bridge required a foundation and tower component which were being built in an incredibly difficult terrain (over 100 feet underwater). The total length of the bridge was 3,460 feet, including 1,595 feet 6 inches between the two towers. The cable and anchoring system was to be much stronger than anything of its day, and were to be constructed using steel, the first time steel was to be used during a major construction project. After taking all factors into account, this project can be categorized as a System Project. Finally we reach the Pace of the project. The Pace of a project is fairly simple concept to determine, yet it may have far reaching consequence when it comes to execution of the project. The four categories the make up the Pace component are: Regular, Fast/Competitive, Time-Critical, and Blitz. For a Regular program, time is not an important factor in the success of a project. Fast/Competitive projects exist when the success of a project is not dependent on the project completing on time; however, timely completion of the project will have a significant impact to the organizationââ¬â¢s competitive advantage and/or bottom line. Time-Critical projects are ones where the success of a project is dependent on completion of the project by a certain time; a delay in completion can mean project failure. Blitz projects are generally projects run during a crisis. Blitz projects often do not have a structured organization, rather decisions are made as quickly as possible to deal with the situation at hand. While the Brooklyn Bridge project was clearly not a Blitz or Time-Critical project, the fact that congress originally provided 3 years to build the bridge, showed a level of urgency desired by the legislating government. Add in the merchants and citizens who stood to benefit from a simple mode of transportation across the East River without having to wait for a ferry; and there was clearly a desire for the bridge to be worked on at a fast pace, resulting in a classification of Fast/Competitive. From the analysis given, the Brooklyn Bridge project could be classified with the following NTCP chart: Figure 2: NTCP diagram of Brooklyn Bridge project ? PROJECT APPROACH For John Roebling, the Brooklyn Bridge project did not begin with approval of the project. In fact, Roebling had been planning a crossing of the East River as early as 1857, when he began making drawings detailing the towers the bridge would require. By 1867, when the New York state legislature had chartered the New York Bridge company to proceed with the construction of the project, Roebling had already devised much of the plans for his bridge. To help in understanding the workings of using a caisson, Washington Roebling, had set out to study caissons being used in Europe for over a year, as well as to pay a visit to the ongoing Eads Bridge crossing the Mississippi, where James Eads was using caissons to build his bridge. Skeptics opposed the idea of the Brooklyn Bridgeââ¬â¢s suspension design by linking it to the vibrational effects from wind that destroyed the deck of the Wheeling Bridge on the Ohio River (Great Bridge p33). However, Roebling was involved only in the repair by using auxiliary stay cables. Thus, this design feature was also incorporated into the future design of the Brooklyn Bridge. To help alleviate public skepticism and ensure the legitimacy of the design, John Roebling hired a panel of seven consultants to approve of the work he was set to perform. John Roebling stated: ââ¬Å"In view of ââ¬Ëthe magnitude of the undertaking and the large interests connected therewithââ¬â¢, it was ââ¬Ëonly rightââ¬â¢ that his plans be ââ¬Ësubjected to the careful scrutinyââ¬â¢ of a board of expertsâ⬠(GREAT BRIDGE, p25). However, it was never Roeblingââ¬â¢s intention to listen to the advice of the experts he had chosen, rather, he had only intended to convince these men that his design would work. To do this, Roebling emphasized the suspension bridge would be built 6 times as strong as needed. Demonstrating his point, he claimed the design of the bridge would be of such that if the four main cables were to break, the bridge would sag, but not break. This way, the span of the bridge would be designed strong enough to hold its own weight without breaking, a very impressive feat for a suspension bridge. Thus John Roebling achieved the objective of his expert consultant group: to use their reputation and status to convince any remaining skeptics that his bridge was stable and proceed forward with the plan. Another characteristic of the approach taken by John Roebling, was that although he had his name attached to the project, he was hardly the face of the project. This task, he left to his eldest son, Washington, with whom he confided much of the plan, still kept secret from the rest of the world. Had it not been for Washington Roeblingââ¬â¢s excellent education, and desire to follow in his fatherââ¬â¢s footsteps, the plans for the Brooklyn Bridge might have been in trouble when in 1869, as the construction of the bridge was set to begin, John Roebling was involved in a freak accident, that crushed his toes at the pier he was surveying for the project. The toes were amputated but rather than seeking medical assistance, he refused to listen to his doctorsââ¬â¢ advice, which some say may have prevented him from developing the fatal bout with tetanus. John Roeblingââ¬â¢s death had left the stakeholders of the bridge in a quandary about how the bridge was going to proceed. However, John Roebling had long desired for his son Washington to take over the project at some point, and had discussed this issue with William Kingsley on a number of occasions. In fact, Roebling had initially suggested that Washington be in charge of the project from the start, but that was deemed unacceptable. Because the detailed designs were kept secret except for John and Washington Roebling, it was easier to pass along the lead of the project from father to son because Washington knew what ideas were going to be implemented in the project. This also prevented someone completely new who did not understand what John was doing and would want to change the ideas. With a clear line of succession, the choice was obvious: Washington Roebling would be allowed to continued the project after his fatherââ¬â¢s death, taking on the role of Chief Engineer. At this point, much of the project planning was done. This included how the design was going to be carried out for the caissons, towers, wires, and actual roadways. Also, requirements needed to be closely considered in order to make sure that stakeholders were satisfied. Construction started on land where the caissons were built. These large wooden boxes had to be the width and thickness the towers were going to be. They were then floated into position and weighted down until they reached the sandy river bottom. Compressed air was inserted into the caissons keeping the water out as they dug deeper. Figure 3: Cross-section of caisson containing muck holes, shafts for people, and pipes where air pressure was pumped in. Due to the compressed air within in the caisson, the workers were limited to 2 hour shifts before the effects of the ââ¬Å"Caissonââ¬â¢s Diseaseâ⬠began appearing. Special chambers called airlocks were developed and helped prevent the negative effects from forming when the finished worker would ascend too rapidly. However, over the length of the project, about 27 workers died from working in the caissons. Digging deeper inside the caissons was extremely slow. The best performance was 6 inches a week (Sheong). Although the Brooklyn towerââ¬â¢s caisson eventually reached bedrock at 44 feet, the Manhattan towerââ¬â¢s caisson continued to go deeper. When the Manhattan tower caisson had reached a depth of 78 feet, and bedrock was still not found, Roebling recalculated whether the tower structure would be able to meet the strength requirements and made the decision to stop digging at this point. The increased weight of the tower was to hold the caisson in place. This delayed the project because there was no way of knowing how deep the bedrock on the Manhattan side was and if 78 feet was stable enough to hold the tower. The next part of the project which needed to be done once the caissons were in place was fill them in and complete the towers. Right before this, a fire broke out in one of the caissons Washington Roebling was inside of. From the rapid ascension, Washington suffered gravely from the ââ¬Å"bendsâ⬠and left him paralyzed for the rest of his life. From his apartment in Brooklyn Heights, Roebling oversaw construction through a telescope while his wife, Emily Roebling, coordinated the construction at the site under his direction. Once the caissons were filled with concrete, the towers started to be built. The entire project was supposed to only take 3 years, however once the towers were finished being constructed, it was already 1876, more than 6 years since Washington had sustained his injury. Initially, John Roebling had designed the bridge to be six times as strong as required. However, as the installation of the wire rope was in progress, it was discovered that some of the wire was a substituted material, not steel. This made it have an inferior quality and was discovered when one of the steel cables snapped. This was supplied by contractor J. Lloyd Haigh. As a result, the bridge was only 4 times as strong as required and was allowed to stand with additional 250 cables. In 1880, Haigh was convicted of fraud and jailed; however, his steel cables could not be replaced because it had already been placed in throughout the bridge which was standing. Figure 4: Wrapping cables in protection. The New York Polytechnic Society devoted several lectures at ââ¬Å"Cooper Union devoted exclusively to the supposed engineering fallacies of the Roebling planâ⬠(Great Bridge p28). To an even greater extent, concern arose that the bridge would interfere with traffic to and from the Navy yard. Thus, Chief of Army Engineers, A. A. Humphreyââ¬â¢s ââ¬Å"decided to appoint his own review panel to give an opinion about it, irrespective of the conclusions reached by Roeblingââ¬â¢s consultantsâ⬠(Great Bridge, p28). ââ¬Å"When it opened on May 24, 1883 the world took notice and the entire United States celebrated. And the bridge, with its majestic stone towers and graceful steel cables, isnt just a beautiful New York City landmark, its also a very dependable route for many thousands of daily commutersâ⬠(http://history1800s. bout. com/od/bridgebuilding/a/brooklynbrid01. htm). However, while there was much public celebration, there was also just much public skepticism. People were both afraid of whether the bridge would be stable enough for people to come across. Even a week after the opening on May 30th, 1883, a public stampede caused by a false panic that the bridge was collapsing caused the death of 12 people and injuries to many others. In order to put this stigma to rest, Roebling hired the ââ¬Å"great showman Phineas T. Barnum to lead a parade of 21 elephants, including the famous Jumbo, across the bridge a year later, in May 1884â⬠(1800s, strollers on bridge, pg11). This proved the stability of the Brooklyn bridge and was no longer feared that it was unstable. ? CONCLUSION Based on the tasks and design used by the Roeblings, we can attempt to classify an NTCP approach the Roeblings used to manage their project. The Roeblings performed an incredible amount of research on previous generations of the product, and John Roebling was considered by many to be one of the premier bridge engineers of the day. Washington Roebling spent a year abroad in Europe studying the use of caissons, and visited a recent project using caissons at depths similar to that planned for the bridge. John Roebling had also performed a fantastic job of marketing the product, proclaiming the bridge to be a transformative marvel for the world to see. By the time the bridge had opened, the entire world was watching, and there had been such a buildup, the President made it a point to be among the first travelers to cross the bridge. This incredible amount of research and marketing is key for a project introducing a novel concept. However, the Roeblings also had a strict design, which had been frozen at the beginning of the construction process. They had not communicated their plans with anyone besides themselves and therefore took serious risk in the case that both engineers had become disabled, as was the case. Luckily for Washington Roebling, while he suffered severe injuries, they had not been grave enough to prevent him from continuing the project with the help of his wife, Emily. John Roebling had also brought on a panel of technical experts to assess his project; however he never intended to listen to any consultation. Rather, than use their expertise to assess the practicality of his project, his only objective was convincing a skeptical public to allow the project to proceed. Although the Roeblings performed many of the requirements of managing a Platform project, they had also managed the project with many characteristics of a Derivative project, therefore it would be best to classify the Roeblingsââ¬â¢ approach a Derivative-Platform approach. Ideally, in order to better fit with the project, the Roeblings should have been more flexible, ensuring that the level of project uncertainty was at a minimal level, before freezing the design plan. They also should have communicated their plans with a committee who could have provided additional perspective that might have noticed any possible flaws that may have existed in the plans. With most projects that contain the level of technological accomplishment of the Brooklyn Bridge project, it was imperative that the designers take the right approach to the match the technical uncertainty of project. The Brooklyn Bridge project required the use of a High Tech technological approach, based on the level of technical achievement and technical uncertainty surrounding the task. A High Tech technical approach would have required flexibility in planning to deal with uncertainty, prototypes and considerable development and testing integrated into the project plans, and frequent communication to the project teams on multiple levels. However, the approach the Roeblings had taken was much different. Instead, the Roeblings had a very rigid design plan, feeling that adherence to the very intricate plan was essential to the success of the project. They had not developed any prototypes, although granted, budget limitations probably would have made a prototype an impossibility. The Roeblings also did not follow a very open communication plan, deciding instead to keep the engineering plan close to the vest. Much of this can be attributed to the engineering culture of the time, as many engineers were very competitive, and most engineers had the mentality of protecting the secrets of their process, rather than helping to promote the science and art of engineering. Because of these characteristics of their project, the Roeblingââ¬â¢s approach would need to be classified as Medium Tech. Incredibly, the project encountered relatively few setbacks, none of which were significant enough to derail the project. However, if we were to improve this process, we would certainly have introduced contingencies to allow some flexibility in the design plan, as well as improve the level of communication from the design team to the construction team. The Brooklyn Bridge was an incredibly complex construction project for its time, and based on our NTCP analysis, given a rating of System-level complexity. A System project usually involves complex planning, with a contractor chosen to operate the project. Characteristics of these projects often include a tight level of control, and a significant level of documentation. The Roeblings had indeed operated the project as a complex project with a System level of complexity. They maintained tight control of the project, and created intricate plans for a complex building process. An organization, the New York Bridge Company, was created for the sole purpose of building the Brooklyn Bridge. This allowed for many of the less exciting, non-engineering related tasks to be delegated to someone other than the Roeblings, who surely would have bristled at the thought of worrying about obtaining funding, filing paperwork for the expenditures of the project, or any other tedious task not directly related to the building of the bridge. The pace of a project is an important determinant in the performance of a project plan. As a Fast/Competitive project, the plan is geared with a focus towards accomplishing the objective as soon as possible, as delays can cause a loss of competitive advantage or loss of revenue for the organization. Fast/Competitive projects are often run with a strong level of coordination with subcontractors, and clear, structured plans to ensure the tasks are organized and run efficiently. However, Fast/Competitive projects are not entirely dependent on meeting a deadline, and although great measures are performed to ensure the completion of a project as soon as possible, delays in the project schedule does not immediately cause project failure. Surely the Roeblings followed a structured plan to organize the tasks and ensured that the process stayed on track, yet were aware of the delays that might occur based on the nature of the task, therefore they followed a Fast/Competitive approach. Figure 5: NTCP diagram of project and the approach taken (shown in red) By analyzing the NTCP characterization of both the project and the approach taken by the Roeblings, we can see that there are some discrepancies between the two. While it seems the Roeblings had properly understood the Complexity and Pace of the project, it seems as though they had underestimated the Technology and Novelty of the project. Luckily enough for them the decisions they made and the project proceeded without any major setbacks, and they ended up with one of the engineering marvels of the 19th century. REFERENCES David G. McCullough, The great bridge: the epic story of the building of the Brooklyn Bridge, Simon and Schuster, 2001 http://en. wikipedia. org/wiki/Brooklyn_Bridge http://history1800s. bout. com/od/bridgebuilding/a/brooklynbrid01. htm http://history1800s. about. com/od/bridgebuilding/ig/Images-of-the-Brooklyn-Bridge/Brooklyn-Bridge-s-Caisson. htm http://www. endex. com/gf/buildings/bbridge/bbridgefacts. htm http://www. racontours. com/archive/caissons. php http://www. civilengineergroup. com/building-brooklyn-bridge. html http://www. eyewitnesstohistory. com/brooklynbridge. htm http://www. youtube. com/watch? v=VvG6DSTej4 U http://scheong. wordpress. com/2010/09/21/the-story-of-the-brooklyn-bridge-a-roebling-family-production/
Subscribe to:
Post Comments (Atom)
No comments:
Post a Comment
Note: Only a member of this blog may post a comment.