The Structural Systems oF Tall Buildings - Tall Buildings: Structural Systems and Aerodynamic Form - page 30

Reinforced
concrete

shear wall

£ ro
7

~29.4m

68.6m

Floor 48

Reinforced
concrete

shear wall

S ri
-t

68.6m

Floors 4-12

Figure 3.18 311 South Wacker Drive, Chicago, USA, 1990
(photo courtesy of Marshall Gerometta/CTBUH)

• the 35-storey, 145 m high Cook County Administration Building (formerly
Brunswick Building) (Chicago, 1964)
• the 65-storey, 293 m high 311 South Wacker Drive (Chicago, 1990) ( Figure 3.18 )
• the 30-storey, 267 m high Al Faisaliah Center (Riyadh, 2000) ( Figure 3.19 )
• the 43-storey, 148 m high Strata (London, 2010) ( Figure 3.20 ) .

3.7 mega column (mega frame, space truss) systems

Mega column systems consist of reinforced concrete or composite columns and/
or shear walls with much larger cross-sections than normal, running continuously
throughout the height of the building. In this system, mega columns and/or mega
shear walls can resist all the vertical and lateral loads ( Figure 3.21 ).
In mega column systems, horizontal connections are of primary importance. Due
to the probable insufficiency of floor slabs acting as rigid floor diaphragms, to support
this behaviour of restraining the columns laterally, belts, vierendeel frames, and
mega braces are used. In this way, all external mega columns and/or shear walls are
connected together to participate in the lateral stiffness of the structure ( Figure 3.21a ).