World Trade Center: Bathtub

One of the famous structures ever built in the entire history of mankind is the World Trade Center. The said structure is said to have hold numerous offices and institutions that plays a vital role in running the economy of America and even to other nations. Moreover, the World Trade Center is also one of tallest buildings ever erected making it attractive to many people around the world. This might also be the reason why the said structure was attacked and was brought down by the alleged terrorists in the year 2001. The structure then was totally destroyed and what only remained was its mere foundation. A Brief History. In the year 1946, the New York state planned to build a structure that would serve as the center for trade and commerce in the said U. S state. Manhattan was chosen to be the location of the planned structure in the year 1962. Numerous professionals were tapped to facilitate the construction of the World Trade Center including Japanese architects and engineers leading the design and construction team. The construction started in the year 1966, starting with the first tower located in the northern part of the site. The north tower was completed after six years and the center accepted tenants even before the tower was totally furnished. A year after the construction of the north tower, another building finished its construction located in the southern region of the site. It was on the same year that the dedication of the World Trade Center commenced. During that time, the World Trade Center was considered as the tallest structure ever built with 110-storey with more than a thousand and three hundred feet in height. Structural Foundation The foundation of the World Trade Center twin towers was constructed with one of the deep foundations ever made. A deep basement was made to support the entire structure of these towers and all of the loads the structure handles. The said basement is also called as the bathtub. This refers to as the underground foundation area not only of the World Trade Center but also of the adjacent buildings located in New York. The bathtub is a distorted rectangle in shape with dimensions equal to almost a thousand feet by five hundred twenty feet with a depth of about seven-storey building. The bathtub is situated down to the rock layer of earth’s foundation. It is then further supported by strong, solid walls that served as the barriers to impede water from the Hudson River to enter the foundation. The said walls are also called as slurry walls. This foundation was made due to the fact that the site where the World Trade Center was erected was man-made. Moreover, the bathtub was built underground and submerged into water. The bathtub designers used pre-fabricated steel as framework of the main foundation of the building. The amount of steel used totaled about two hundred thousand tons to supply the needs for the foundation of the World Trade Center. Braces were placed to support the slurry wall aside from the supplemental support provided by the bedrock. The Foundation Design of the World Trade Center Source: www. wc7. net The Bathtub The foundation designed by the architects and engineers was seen to be massive, just as what should be considering the height of the buildings to be erected on top of the said foundation. It is a must for any gigantic structure to cling its foundation on the solid rock located beneath the earth’s ground. To attach the foundation to the bedrock, the construction workers dug enormous mass of soil and brought it up on the earth’s surface. Another challenge that was faced by the builders is that the site is near a body of water. The water coming from the river may interfere in the construction of the foundation of the World Trade Center. To resolve this problem, the workers used digging machines to create channels down to the solid rock area of earth. As they dig troughs, the workers placed a slurry wall made up of bentonite. Bentonite is an expensive type of clay that is effective in impeding water from flowing. The said material would go within the dug channels, which would effectively block the water coming form underneath the surface. Pictorial Representation of the Foundation for the World Trade Center Source: www. deepexcavation. com Slurry Wall Slurry walls, also known as diaphragm wall is a type of structure created and casted in a certain trough or channel. The trench was hinged by an expensive type of clay called as bentonite that is specified to impede soil erosions into the foundation. In other terms, slurry walls refer to a wall that is utilized to obstruct stream flow. There are equipments that are being used in applying the slurry walls in building foundations. Some of the tools used include hydromills, hydraulic clamshells and other trenching equipment. Slurry Wall History The first slurry wall that was constructed was in the year 1950 in Italy. Four years earlier, slurry walls undergone series of tests to assess its capabilities as a part of foundation of a big structure. In the year 1960, this technology was introduced in the United States of America by the European building designers. Various buildings in the US were built using the slurry walls which includes structures located in New York and California. It was only after the said structures were built that the World Trade Center was erected and used the slurry walls in its foundation. Other key states utilized the technology like Boston and Washington D. C. Slurry Wall Construction Slurry wall construction can be summarized into four steps, as shown in the figure below. The first procedure is to create a trench and applying the clays used in forming the slurry walls (A). After this procedure, a steel cylinder is inserted at the ends of the excavated areas (B). After that, a fortification cage is placed down the trench to add more support in the foundation (C). The last procedure is the concreting of pipes where the buildings would be attached. Pictorial Presentation of Slurry Wall Construction Source: www. deepexcavation. com Slurry Wall Applications There are numerous applications that can be associated with the utilization of slurry walls. One of its major applications is to serve as earth retention barriers for tunnels, subterranean vaults, and excavations. Another application of slurry walls is for blocking water penetration onto the foundation. Increasing the strength of the foundation of any structure is also one of the major applications of these slurry walls. Moreover, contamination prevention is also one basic application that is used by many architects and engineers. A gas leakage prevention form landfill is also one application that can be associated with the slurry walls. However, there are also limitations in using slurry walls in the construction of foundation. Construction of slurry walls requires heavy equipments that consume a lot of space in the construction site. Operational costs are also expensive because of the materials needed in the construction of slurry walls. Slurry Wall: After 9/11 Attack The attack made on the twin towers of the World Trade Center caused severe damage into the structure. Furthermore, after the fall of the entire structure down to the ground, many people worried about the possible damage on the slurry walls and the bathtub of the World Trade Center which can possibly affect the adjacent structures built near the vicinity of the World Trade Center. Water penetration from the Hudson River can provide damages on other structures and can also bring flooding in the nearby areas. Because of these concerns, a team of experts was sent to check the status of the said walls and inspected the entire foundation site continuously using various equipments like inclinometers and other monitoring devices. Rehabilitation of the said walls were made in order to maintain the strength of the foundation of the World Trade Center and to avoid recurring problems that might bring more harm to the people and properties in the said region.