Trump International Hotel and Tower, Chicago
Largest Concrete Poured Skyscraper
Trump International Hotel and Tower is designed by Skidmore, Owings & Merrill LLP (SOM). It is the tallest building in US and was tallest building in North America since Sears Tower raised. A total of 175,000 cubic yards of concrete used to construct the 2.7 million square foot high rise. Laborers began laying the foundation (October 1st , 2005) working 24 hours straight to pour 5,000 cubic yards of concrete to create a base that is 60 feet wide, 200 feet long and 10 feet deep. This pour was the largest single Concrete pour in the history of construction industry then.
 |
Chicago is not only a city of international hub for finance, commerce, industry, technology, telecommunications and transportation but also considered as the best 'Global City'. It ranks seventh place in the world in Global City Index 2014. The building structures in Chicago as made other populous cities to turn towards and wonder about the tall buildings in one particular town. Chicago is a most fabulous city and is the third largest city in US. One of the outstanding skyscraper is ‘Trump International Hotel and Tower’ located in a richest state Illinos. The fourth tallest building in US; which is named after Billionaire Real Estate developer Donald Trump.
Semblance
Engineered with a stiff internal concrete core and outriggers, Trump Tower's design allows the facade to be opened up and sheathed in a diaphanous glass curtain wall. The facade is adorned with clear anodized aluminum and mirror finished stainless steel that reflects and refracts light from the sun. Outset from the glass surface, the mullion system provides density and thickness as well as a metallic quality to the otherwise flush glass wall.
The tower's design is also strongly influenced by the presence of water. In the lobby for instance a 10.6m high (35-foot) structural glass wall, hung from the second floor and resembles a cascading wave. Free of steel supports; the wall is composed of a series of angled glass fins that provide open and unobstructed views of the waterfront.
Each is made of thermal pane glass with a special coating to retain heat in the winter and cool air in the summer. It takes four workers to install each one, beginning with ironworkers Dan Koney and Jerry Doherty wheeling the panels to the building's edge and attaching them to a cable.
Floor
Floor structures are generally flat plates or flat slabs. Special thick, heavily reinforced slabs are required at and above the mechanical levels. Floor slab thicknesses are increased at many levels to limit acoustic and vibration transmission. Typical residential floors are 9-inch thick flat plates spanning up to a maximum of 30 feet without perimeter spandrel elements. This construction minimizes the structural depth of the floor, allowing higher ceiling heights. Tower columns are typically 2-by-4-feet rectangular sections at the top of the building and 6-foot diameter circular sections at the base.
The Spire
Trump Tower's spire rises 69 meters (226 ft) above the roofline bringing the total building height to 415 meters (1,362 ft). Constructed from three sections of structural steel clad in fiberglass; the spire tapers from a three meter diameter at its base to a 1.2meters (4ft) diameter at its top. A crane was used to erect the bottom 28 meters (90 ft) of the spire on the tower’s roof but the installation of the top of the spire required a helicopter to hoist the pinnacle into place. Fully finished; the spire consists of 1,120 pieces of steel, 7,200 bolt assemblies, and 126 fiberglass panels.
The Penthouse
All 758 condominium units at Trump Tower are designed for luxury, but none more so than the 89th-floor penthouse, which has seven bedrooms, eight baths and occupies 14,280 square feet. Each bedroom has a view, as does the kitchen, dining room, living room and family room. It also has an art gallery and a media room.
Like the other condo units, it also features hardwood floors, Italian wood cabinetry by Snaidero, granite countertops, Miele stainless appliances, concealed dishwasher and refrigerator, limestone floors and walls in the bathrooms, twin porcelain sinks, oversized whirlpool bathtubs and separate showers.
The expected occupant is Donald Trump, but the sales staff says he'd willingly give it up for an eager buyer. The asking price: $28 million.
Structural Detail
A core and outrigger system provides lateral stability for the Trump Tower. Large outrigger elements at the mechanical levels tie the concrete core to perimeter columns, significantly increasing the building’s lateral stiffness as well as its resistance to overturning due to wind. The core is located at the center of the building and consists of four I-shaped and two C-shaped walls at the base and gradually reduces to two I-shaped walls above the final setback at level 51. The webs of these I- and C-sections are oriented in the north south direction are 18 inches (460 mm) thick and are 41 feet (12.5 m) long. The flanges of the sections are oriented in the east west direction is 48 inches (1.2 m) thick and range from 9 feet to 22 feet (2.7 to 6.7 m) in length. Above the entries to the elevator cores at each level 48inch (1.2m) wide by 30inch (0.8-m) deep reinforced concrete link beams connect the flanges of adjacent walls.
The outrigger effect is most pronounced in the shorter direction of the building (north south) as the width of the lateral system increases from 49 to 140 feet (15 to 43 m) when the perimeter building columns are engaged. The outriggers are large reinforced concrete wall beams, 66 inches (1.7 m) wide and 17 feet 6 inches (5.3 m) deep, that extend from the flanges of the core walls to the exterior columns at three of the double height mechanical floors in the tower (levels 28-29, 50-51, and 90-91). These outrigger levels occur just below the building setbacks and the outriggers also serve as transfer girders as the columns are relocated at the facade. At the lowest setback transfer girders allow for a column free space at the ten parking levels. Perimeter belt walls at the roof and the three mechanical levels provide additional torsion stiffness, redundancy and also serve to equalize column loads along the perimeter.
Typical residential floors are 9inch (230-mm) thick flat plates spanning up to a maximum of 30 feet (9.1 m) without perimeter spandrel elements. This construction minimizes the structural depth of the floor allowing higher ceilings. Tower columns are typically 2 by 4 feet (600 by 1200 mm) rectangular sections at the top of the building and 6-foot (1800-mm) diameter circular sections at the base. The superstructure is supported by a total of 57 rock caissons. The tower columns are supported by 33 of these caissons, which are up to 8 feet (2.4 m) in diameter and stabilized by a series of caisson caps and grade beams.
Mat Foundation Concrete
The mat pour in late consisted of approximately 5,000 cubic yards (3,800 cubic meters) of 10,000 psi (69 MPa) self-consolidating concrete over plan dimensions of 200 x 60 feet (60 x 18 m) in a single continuous pour. The pour was accomplished in a period of 22 hours and required more than 30 ready mix trucks making a total of 600 trips to the job site. The choice of SCC for the mat was based on the ease of placing concrete and finishing in a confined below grade area. It is believed that the mat foundation pour for the Trump Tower represented the largest single SCC placement in North America to date.
High Strength Concrete
Trump Tower is not only a very tall building; it is also quite slender; the aspect ratio of the tower, measured as the overall height divided by the smaller base dimension, exceeds 8 to 1. Such slender buildings are known to be significantly influenced by the dynamic nature of the wind and its interaction with the structure. Concrete was chosen as the primary structural material for the Trump Tower to take advantage of its ability to provide a highly massive frame with high damping. The high lateral stiffness of the tower was accomplished by using high modulus of elasticity concrete in the massive column, wall, and outrigger elements. All of these factors resulted in predicted peak accelerations at the topmost occupied floors that are comfortably within the ISO criteria for residential buildings.
Unique Design Philosophy
The magnitude of the applied loads and the scale of the outrigger elements the structural design was unique and extremely challenged the architects. Large tie forces are resisted by top and bottom longitudinal reinforcing and vertical ties. The heavy longitudinal reinforcing steel must pass from the thicker outrigger through the thinner core wall web to transfer forces between the columns and core. To reduce congestion, all primary reinforcing bars in the outrigger levels are U.S. Grade 75. Further in three especially tight locations; high strength structural steel plates with welded shear studs are used in lieu of reinforcing bars to transfer the necessary forces through the core wall web.
The outriggers are also significantly affected by differential shortening of the concrete columns and core walls resulting from creep and shrinkage. The columns typically have higher axial stresses and therefore shorten more than the core walls transferring load through the outriggers into the core walls. A special analysis was used to account for time dependent effects; including creep, shrinkage, construction sequencing and the variation of material properties. This analysis included eight different finite element models of the building each representing a different period in time during and after the construction. The calculated forces in the outriggers and walls were taken into account in the forces applied to the strut and tie model for the design of the outriggers and were also incorporated into the design of all elements of the lateral system.
A series of high performance concrete mixtures specified by SOM and designed by Prairie Material Sales, Inc., are advancing the state of the art. Concrete strengths of 12,000 psi (83 MPa) (cylinder strength) at 90 days have been specified for all vertical column and wall elements up to level 51. Further, to reduce the heat gain in the massive elements, the high-performance SCC incorporates slag cement, fly ash, and silica fume, as well as Portland cement.
The tower structure is designed to limit the perception of motion by the building occupants during wind events to acceptable levels and for the stiffness of the concrete is critical. The modulus of elasticity of the high strength concrete was therefore specified to at least achieve the modulus of elasticity values indicated in the ACI 318 equations. In contrast to the stringent minimum strength requirements in ACI 318 concrete modulus of elasticity may be specified on an average basis. Somewhat lower modulus values in local areas are therefore acceptable as long as the average value remains as specified. Further, such modulus values may be obtained at a later date.
Sustainable Elements
The tower employs three main sustainable strategies that translate into considerable cost savings. Chicago River water is used to cool the building. This cooling system allows water to re-circulate back into the river, avoiding the costly and more energy-intensive and wasteful requirements of conventional cooling, which would require a pump and cooling tower system to eject water vapor via the roof. A computerized control system regulates the temperature and ventilation of the tower and determining how much the air must be conditioned.
Partial green roofs can be found on the tower’s terrace levels. The roofs will have a longer life span than standard asphalt, since it is protected from the ultraviolent radiation and extreme fluctuations in Chicago weather that can cause roof membranes to deteriorate. The insulation provided by the green roofs also helps to moderate the heat island effect, improve storm water management, purify air, water and reduce energy consumption.
Each of the tower’s 3m tall by 1.5m wide (11 by 5 feet) curtain wall panels are made of thermal pane glass encased in aluminum with dual low-emissivity coatings that help to retain interior heat in the winter and cool air in the summer. The double thick glass also decreases the amount of air seeping through while tinting reduces summer sunlight and keeping inside temperatures cooler.
Other Features
The completed Trump Tower program features 486 luxury condominium residences, 339 five-star hotel rooms in the Trump International Hotel a world class signature restaurant with outdoor terrace; banquet and conference center facilities, a health club and spa, one thousand parking spaces and 80,000 square feet of retail space along the Chicago Riverwalk. The project completes its enhancement of the downtown community with a 1.2 acre terraced park to the east of the tower and 500 feet of riverwalk connecting Michigan Avenue to State Street.
Apart from the building design, the mechanical rooms in the basement where it points the cooling system which utilizes water from the Chicago River to cool the building. A computerized control system regulates the temperature and ventilation of the tower, determining how much the stair must be conditioned. Further, partial green roofs help to naturally insulate the building.
Conclusion
The Trump International Hotel and Tower is scheduled for fall 2009. However the owner desires to open the hotel and some of the residential levels before the topping out of the structure has he wished. The collaboration between the designers, construction manager, contractors, and the City of Chicago has made it a memorable huge building. The spire is a structural steel space truss clad in fiberglass. Erection of the upper eight segments of the spire was accomplished using a Sikorsky S61 helicopter. It was the exclamation point to cap off a world class building combining rigorous engineering state of the art materials, and graceful architecture.
Fact Sheet:
Project: Trump International Hotel & Tower
Place: Chicago, Illinois
Site area: 153,685 ft Square
Project area: 2,600,000 ft Square
Number of Stories: 92
Total Building Height: 1,388.50 ft
Utility: Commercial office, Hospital, Mixed Use, Residential
Developer: The trump Organization
Architect: Skidmore, Owings & Merrill
Structural Engineering: Skidmore, Owings & Merrill
MEP Engineering: WMA Consulting Engineers
Main Contractor: Bovis Lend Lease
Facade: Permasteelisa Group
Wind: RWDI (RWDI is a member of the CTBUH at the Donor level)
Material supplier: Elevato-KONE and Sealants Dow Corning Corporation
Retail space: 80,000 square feet
Residences: 472
Hotel rooms: 339
Parking spaces: 1,000
Land cost: $73,000,000
Concrete: 180,000 cubic yards
HIGHLIGHTS:
- According to the Chicago Tribune, SOM built about 50 models of the building before getting the design they wanted.
- At the time of its completion it was the largest reinforced concrete building in North America.
- This building is made of concrete instead of steel to reduce sway and maximize window space.
- 17 March, 2005:- Construction officially begins on the Trump Tower.
- 2 October, 2005: The concrete for the foundation mat arrives in what is called the "Big Pour." Dozens of truck work continuously for almost 24 hours to pour 5,000 cubic yards of wet concrete into an area 66 feet wide, 200 feet long, and 10 feet deep. This creates an underground anchor for the building. The concrete is mixed to withstand 10,000 pounds of pressure per square inch.
- February 1, 2008: Construction reached the 60th floor.
REFERENCE: