Outline Building Overview Design Guidelines Structural System How the System Works Structural Intervention
Federal Reserve Bank
Structural Intervention
Ideas Load Analysis & Breakdown Comparison
HG 1 - B
Conclusion &
Deandra Adellia S. -
1706973451
Gabriella S
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1706037781
M.F. Pristantyo
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1506671796
Evaluation
Building Overview Marquette Plaza
Federal Reserve Bank Architect:
Gunnar Birkerts Year of Projects:
1973
Designed by Gunnar Birkerts, it was home to the Federal Reserve Bank of Minneapolis from 1973 to 1997 (hence, many people refer to it as "the old Federal Reserve building"). Designed much like a suspension bridge, most of the original floors are supported by two sets of catenary cables. Underground chambers were used for vault space, and an external elevator shaft was attached on the east face of the building to connect a ground-floor lobby with the rest of the building. There was originally a gap between the lobby and the rest of the above ground structure to emphasize the construction method.
Design Guidelines The building is required to span over the public square underneath it so that it has a continuous landscape which can provide broad views and place for people to stay.
Another concept of the building is for it to receive maximum sunlight by the use of curtain wall.
Continuous Landscape
Maximum Sunlight
Structural System
Catenary suspended structure which popularized by Bridges that use two tower to support load that held by tensioned element that shape natural curvature.
Compression Truss torque
“Catenary� Tensioned Element
torque load
Tower
compression tension
tension
load load Catenary Bridges
Federal Reserve Bank
The differences lies in the existence of compression truss in the top of the building to resist the torque of both tower.
How the
system works
Front Elevation The third tower in the middle are build to protect the building from lateral load (mainly wind load)
Top View
Structural Intervention Ideas
Parameters: The primary & overall form should be the same as the previous Federal Reserve Bank.
The gap in between lobby and the rest above the ground should be present.
Try to use a different structural ideas and mechanism
Inverted Catenary
Diagrid Belt
Exo-Suspended Cantilever
Key Ideas
Key Ideas
Key Ideas
Changing tension receiving component into compression receiving component
Dividing the load into 2 separated load. And then the load are transferring load to core uniformly by using perimeter diagrid column
Evaluation The system is too similar with previous existing structural system. So we won’t learn anything new from experimenting this idea
Evaluation The load in the center ( in between the twin towers) would be too much.
Dividing the load into 3 separated load and each carried by a tower as a cantilever. The torque is cancelled by adding cable that anchored to the ground.
Evaluation The cable system takes too much space
1
D e s i g n P r o c e s s
2
The floor are separated into three different groups to reduce the cantilever span
3
The core are extended 12m beneath the ground, and then basement as balance counter are added in the direction opposite to the cantilever floor
5
The core are added that support each of the cantilever floor
4
The Core are pre-stressed with tensioned cable to withstand the enormous torque and connected to the balance counter
The pile foundation were added that combine vertical and diagonal element to help withstand the torque
6
To stiffen the cantilever, instead of making the slab thicker, we choose to add internal column that transfer vertical load to belt trusses that connect with the core
7
8
Because of the separation gap between three cantilever, exoskeletal bracing are needed to withstand lateral load. The lateral load are mainly distributed to the middle core
Additional diagonal column are added beneath the trusses to increase the stiffness of the cantilever
Structural Elements
Top view
Left view
Front view
Rear view
axonometry
Right view
Core Cantilever slab Core Truss Exoskeleton Bracing Foundation
Load Analysis & Breakdown Load from each floor are carried vertically by column From column, the load are transferred to cantilever truss into the core The core carried the load into the ground
The foundation is expanded on the opposite side of the cantilever to help resist torque
The exoskeleton bracing transfers the lateral load from the floor slabs and truss to the core
Load Analysis & Breakdown
Cantilever slab
Cantilever slab Truss
Column Truss
Core
Core
Vertical Load
Foundation
Lateral Load
Foundation
Comparison Precedent
The precedent uses suspended catenary structure. ● ● ●
● ●
continuous floor slab from one end to another suspended catenary element to transfer load upwards truss on top of the building to transfer the suspension load and as the compression element 2 core located on each sides and 1 core in the middle foundation below each core
Reconstructed
The experiment uses cantilever structure. ● ● ● ● ●
3 separated floor slabs columns on each floor to transfer vertical loads truss on each 5 floors as the cantilever element 2 core located on each sides and 1 core in the middle foundation below each core expanded to withstand the torque
Conclusion & Evaluation The reconstruction experiment shows that we can construct a building with specific form and concept with various types of structure. Both of the suspended and the cantilever structure can efficiently receive the lateral and vertical load with its structural elements. Based on the experiment and the comparison between the two structures, we can say that the existing structure that is implemented on the precedent (suspended catenary) is more efficient on transferring the loads with less structural elements, also providing more space to occupy?
Maquette Documentation