土木工程外文翻译-- 迪拜的设计

外文资料翻译 Design, Construction Structural Details of Burj Dubai The goal of the Burj Dubai Tower is not simply to be the world s highest building it s to embody the world s highest aspirations. The superstructure is currently under construction and as of fall 2007 has reached over 160 stories. The final height of the building is 2,717 feet 828 meters. The height of the multi-use skyscraper will comfortably exceed the current record holder, the 509 meter 1671 ft tall Taipei 101. The 280,000 m2 3,000,000 ft2 reinforced concrete multi-use Burj Dubai tower is utilized for retail, a Giorgio Armani Hotel, residential and office. As with all super-tall projects, difficult structural engineering problems needed to be addressed and resolved。 Structural System Description Burj Khalifa has refuge floors at 25 to 30 story intervals that are more fire resistant and have separate air supplies in case of emergency. Its reinforced concrete structure makes it stronger than steel-frame skyscrapers Designers purposely shaped the structural concrete Burj Dubai - Y shaped in plan - to reduce the wind forces on the tower, as well as to keep the structure simple and foster constructibility. The structural system can be described as a buttressed core Figures 1, 2 and 3. Each wing, with its own high perance concrete corridor walls and perimeter columns, buttresses the others via a six-sided central core, or hexagonal hub. The result is a tower that is extremely stiff laterally and torsionally. SOM applied a rigorous geometry to the tower that aligned all the common central core, wall, and column elements。 Each tier of the building sets back in a spiral stepping pattern up the building. The setbacks are organized with the Tower s grid, such that the building stepping is accomplished by aligning columns above with walls below to provide a smooth load path. This allows the construction to proceed without the normal difficulties associated with column transfers The setbacks are organized such that the Tower s width changes at each setback. The advantage of the stepping and shaping is to confuse the wind 1. The wind vortices never get organized because at each new tier the wind encounters a different building shape. The Tower and Podium structures are currently under construction Figure 3 and the project is scheduled for topping out in 2008。 Architectural Design The context of the Burj Dubai being located in the city of Dubai, UAE, drove the inspiration for the building to incorporate cultural, historical, and organic influences particular to the region。 The center hexagonal reinforced concrete core walls provide the torsional resistance of the structure similar to a closed tube or axle. The center hexagonal walls are buttressed by the wing walls and hammer head walls which behave as the webs and flanges of a beam to resist the wind shears and moments. Outriggers at the mechanical floors allow the columns to participate in the lateral load resistance of the structure； hence, all of the vertical concrete is utilized to support both gravity and lateral loads. The wall concrete specified strengths ranged from C80 to C60 cube strength and utilized Portland cement and fly ash Local aggregates were utilized for the concrete mix design. The C80 concrete for the lower portion of the structure had a specified Young s Elastic Modulus of 43,800 N/mm2 6,350ksi at 90 days. The wall and column sizes were optimized using virtual work . La Grange multiplier ology which results in a very efficient structure Baker et ah, 2000. The reinforced concrete structure was designed in accordance with the requirements of ACI 318-02 Building Code Requirements for Structural Concrete The wall thicknesses and column sizes were fine-tuned to reduce the effects of creep and shrinkage on the individual elements which compose the structure. To reduce the effects of differential column shortening, due to creep, between the perimeter columns and interior walls, the perimeter columns were sized such that the self-weight gravity stress on the perimeter columns matched the stress on the interior corridor walls. The five 5 sets of outriggers, distributed up the building, tie all the vertical load carrying elements together, further ensuring uni gravity stresses hence, reducing differential creep movements. Since the shrinkage in concrete occurs more quickly in thinner walls or columns,