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8. Answer the questions to parts I and II:

1. What do the developers of the complex on the west side of Manhattan hope for?

2. What was located on the site before?

3. How has the site been used after Garden’s demolition?

4. Who is the new owner of the site?

5. Who designed a master plan?

6. Why was Childs in an unusual position?

7. How was the project planned?

8. What do the WWP and Rockefeller Centre have in common?

9. How is the public plaza decorated?

10. Is there any drive for cars?

11. How many stories are the towers?

12. In what way is the relationship of the townhouses to the street provided?

13. What is the design of the commercial tower?

14. In what way is the verticality of the shaft defined?

15. Do you like the appearance and the character of the commercial tower?

16. Who designed the residential tower and townhouses?

17. How can people access the residential building?

18. What will be constructed beneath the plaza?

19. What is planned inside the ring of residential building?

20. Can you characterize the complex in one word?

9. Read part III and answer the questions after it. Make sure you can explain the following terms and word combinations from part III.

Excavation of the rest of the site

Parking lot

Excavation and foundation contractor

To deal with a maze

Underground debris

To set the construction schedule back

Rebar

Cut with torches

Equipment housed in the basement

Oil tank

Rocky subsurface

Explosive charges

Close blasting

A close and more precise line

Spacing

To chip away

To turn to a backhoe

To renovate a subway entrance

Token booth

Superstructure

Exterior tube

Lobby

Grade level

Granite-clad columns

Prefabricated off the site

Option

Faced with granite

Dowels

Preset holes

Vaulted ceiling

Coffered sections

Fiberglass-reinforced gypsum

Joist framing system

To be within the footprint

Transferred loads

Structural engineer

Associate partner with

Mechanical mezzanine

Project manager

Rigid frame

Bays

Setback (n)

Wind stresses

Braced core

P art III. Demolition. A three-story brick building in a corner of the site was quickly demolished in two days. But when excavation of the rest of the 200 x 800-ft site began, no one knew what was below the asphalt parking lot. Excavation and foundation contractor Delma Construction, New York City, discovered that the old Garden's reinforced concrete floor slab had simply been cut in half and dumped into the building's basement. Instead of a simple excavation, Delma had to deal with a maze of underground debris. The process set the construction schedule back about a month, says Dominic Fonti, the commercial tower's project manager for HRH Construction Corp., New York City. Rebar had to be cut with torches before it could be removed by crane.

The excavation process also uncovered all of the mechanical equipment that had been housed in the basement of the old Garden. Obstacles included an oil tank full of oil that had to be emptied before it could be removed from the site, Fonti says.

To excavate the site's rocky subsurface, explosive charges had to be kept very small because blasting was so close to an active subway line. This slowed the construction schedule another three to four weeks, says Fonti. To get a close and more precise line for the charges, workers drilled holes that were about 6 in. on center. This spacing meant that the rock wall was just chipped away. When workers were as close as 20 to 25 ft to the subway, they turned to a backhoe fitted with a hydraulic hammer.

Z eckendorf had agreed to renovate and expand a subway entrance that will be part of the commercial tower. The entrance had been sealed 22 years ago when the old Garden was demolished. When workers opened it, they found lots of dust and an old token booth that was later removed—but no graffiti. It is "probably the only subway entrance [in New York City] untouched by graffiti," adds Fonti. During the excavation, the only part of the old Garden structure that was retained was its north foundation wall. Nearly 100 lin. ft o f it was integrated into the foundation wall system for the commercial tower. The superstructure of the 778-ft-high commercial tower consists of an exterior tube with a braced frame at the core. The tube resists most of the overturning moment and the braced core resists most of the shear forces.

A n arcade, elliptical in plan, surrounds the lobby at grade level. The arcade's 25-ft-high granite-clad columns were prefabricated off the site. Fonti says this option was faster and saved money on labor. The 4-ft-high sections are 6 in. thick and consist of a concrete layer faced with granite. The sections are connected on the site with dowels inserted into preset holes. The 35-ft-high vaulted ceiling in the arcade is also made of prefabricated sections. Its coffered sections, with ornamental borders, are made of fiberglass-reinforced gypsum. They are hung from a metal joist framing system.

Although the arcade is open to the exterior, it is still within the footprint of the structural tube. To get the tube's loads around the three-story arcade, they are transferred to the corners of the building through heavy diagonal W14 sections.

Structural engineer Richard F. Rowe, an associate partner with SOM, explains that transferring the loads "over a couple of stories is more elegant, so the load is gradually distributed to the places that you want it." He adds that it is important to recognize that the transfers take place so you can't see them from the exterior." A network of transfers is located between the second and fourth floors. Transfers also take place in a 4 to 5-ft-high space below the second level, used as a mechanical mezzanine, says Robert P. Sanna, one of HRH's project managers on the job. Above the fifth floor, wide tube columns are used as structural members instead of W14s. Structural engineer Robert A. Halvorson, a partner with SOM, adds that the rigid frame is interrupted between the 41st and 43rd floors. The columns stay in the same location, but a 2-ft recess of the beams between the 19-ft-bays provides a setback for exterior lighting equipment to be installed. Halvorsons explains that the wind stresses are low enough at that height that the rigid frame can be interrupted without problem.

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