I M Pei's Unbuilt Hyperboloid, reimagined after 60 years

Figure 1 Pei's Hyperboloid drafted by author

In 1956, I. M. Pei proposed the Hyperboloid, a hyperbolic paraboloid tower to replace the Grand Central Station in New York. The 102 storey tower was to have a height of 1,497 feet eclipsing the Empire State Building. Though, Architectural Record said it "resembled a bundle of sticks," it was a simple geometric visualization of the hyperboloid. The steel exoskeleton was meant to withstand a nuclear attack. In any case, it was a unimaginable for the New Yorkers to see the demolition of the Grand Central Station and the proposal was cost prohibitive.

CHALLENGES IN DRAFTING 

• The biggest hurdle in the drafting in Revit was the lack of information about the building. Wrong dimensions would make the building appear disproportionate. Only the following were available from which the dimensions were derived and parameters formed in Revit.

Figure 2 Facts about the Hyperboloid (http://forum.skyscraperpage.com/showthread.php?t=151888)

•  Though the building appears simple, it has many complexities such as the details of the exoskeleton, crown, the base and such. 
• The building could be made by making multiple envelopes, each requiring separate sorts of effort.
• Each envelope required its own custom panel pattern.

The building was designed in Revit by breaking down the structure into 4 primary components:

1. The main mass of 1,350 sq.ft. height.
2. The base structure.
3. The exoskeleton of the mass.
4. The crown.

The parameters used are as follows:

Figure 3: The final parameters used followed by the earlier set of parameters.
 
From the base floor plate area, the radius was derived and the other radii were related to it.

Heights were assigned in similar fashion. 

Figure 4 Revit modelling by author

 The ORIGINAL REVIT FRAME of the Hyperboloid.

 

Figure 5 Revit modelling by author

THE MASS

Created by extruding the three circles. There is a top viewing deck as well.

Figure 6 Revit modelling by author

All the parts of the model were created separately as families (crown, base, envelope exoskeleton, mass) and combined into the following mass family. The mass family is parametric by nature and the only parameter to be entered is the base plate radius and height. From that, all other dimensions are derived to preserve the proportion of the building. The following depict it:

 

THE INDIVIDUAL PARTS OF THE MODEL

1. THE BASE

Figure 7 Revit modelling by author

 

Figure 8 Revit modelling by author

2. THE EXOSKELETON

The radii were increased by 2' so that this envelope won't overlap with the mass.

Figure 9 Revit modelling by author

The bolt detail was made in the custom panel.

 

Figure 10 Revit modelling by author

Figure 11 Revit modelling by author

3. THE CROWN

This was the trickiest part owing to the design.

Figure 12 Revit modelling by author

The triangular patttern was created on Curtain Panel pattern based, loaded into the crown family. The family was then loaded into the project. These triangular frames had to be deleted alternatively at the project level to get the desired effect. Then the gaps were joined by linear members which were created in another generic model adaptive family.

 

Figure 13 Revit modelling by author: The linear members connecting the triangles.

Previous option for the crown.

Figure 14 Revit modelling by author

After that a New Project File was opened.

The mass combining all the families into one mass family.  This mass family was loaded into a new architectural Project file.  

1. Dimensions: Datum was marked for first 10 storeys and then intermittently till the top. This was to create the dark bands later on.
2. From the Massing & Site, the floors, roof and the curtain panels were created.
3. At certain intervals, concrete walls 2 storey high were made. They were at the levels 6,7,26,27,46,47,66,67,86,87,106,107,126 and 127.  This completed the main mass.
4. The base was loaded then.
5. The exoskeleton was loaded.
6. The crown was loaded and aligned to the exoskeleton before its floor massing was clicked.

THE ASSEMBLED STRUCTURE

Figure 15 Revit modelling by author

On the project, we can see bands on the building after certain intervals. These are the 8 service floors which were added individually in the project, by creating the associated floors and adding concrete walls which overlap the curtain panels.

 THE FINAL RENDERING

 

Figure 16 Final rendering by author

 

Figure 17 Final rendering by author

Figure 18 Final rendering by author

 Figure 19 Interior at the top level

 Figure 20 Interior at the top level


The video:

REFERENCES

• http://forum.skyscraperpage.com/showthread.php?t=151888 
• https://www.elegran.com/blog/2014/04/the-nyc-that-could-have-been
• http://ny.curbed.com/2013/2/25/10270414/i-m-peis-circular-tower-that-almost-replaced-grand-central
• https://www.6sqft.com/this-80-story-i-m-pei-designed-tower-almost-replaced-grand-central/
• https://vimeo.com/19698052