INSTRUCTOR: ANNE NICHOLS
General information
Location: Hong Kong, China
General information
BANK OF CHINA
Architect I. M. Pei
Structural engineer Leslie Robertson
Height from street to roof 1028ft (367.4 m)
Number of stories 70 stories
Number of levels below ground 4 stories
Space area 1.4 million square feet
Ground floor area 29,000 square feet
The highest floor area 7,265 square feet
Building use Office
Building cost $150 million
General information
Frame Super frame, truss
Frame material Steel, concrete
Basic wind velocity 143mph
Type of structure Cross-braced space truss
Foundation conditions Square granite clad base(170 feet in length)
Footing type poured in place, caisson
Ground floor column size 14’×26’
Column material composite concrete and steel
Floor slabs 4” thick
General information
Building height comparison
General information
Inspired by bamboo
symbolic of strength,
vitality, growth and
enterprise
General information
Awards
2002 "Excellent" Award of Hong Kong Building Environmental
Assessment Method
1999 Ten Best Architecture in Hong Kong, HKIA
1992 Marble Architectural Award
1991 AIA Reynolds Memorial Award
1989 Award for Engineering Excellence, ACEC
1989 Certificate of Engineering Excellence, NYACE, etc.
Plans
Square plan
four prism towers rise to
different levels:
25th, 38th, 51th, 70th
Story 51& 52 Story 38
The 25th floor: the fifth
column, exterior
Story 25 Story 4
Plans
Square plan
four prism towers rise to
different levels:
25th, 38th, 51th, 70th
The 25th floor: the fifth
column, exterior
Form & Structure
The shape of the envelope changes
dramatically
Maintaining the purity of the geometry was
the challenge around which the very
structural feasibility of the project turned.
Structure design concept:
a series of triangles as a super frame.
Facade
X’s vs. diamond’s
refuge floor
change the form
Facade
• “Form and decoration were not
enough. The building must be
structurally logical and elegant.”
------ Pei
Facade
• The over-all result of the
façade’s handling is a
crisp surface that appears
tightly drawn across the
faceted faces of the
building.
Members
Joints:
A critical joint at which the vertical,
horizontal, and diagonal members of
the steel frame all come together.
This joint is not a welded connection,
nor is it all steel.
A block of reinforced concrete that
envelopes all the columns, stiffening
trusses, beams, and cross-braces.
Lateral loads
• Hong Kong is in a
typhoon zone . With
wind loads twice that
for New York City,
and equal to four
times the earthquake
load for San Francisco.
Lateral loads
Trusses used in lateral force system
Lateral load: wind load analysis
6.30k Pa 314m
5.76k Pa 288m
4.72k Pa 236m
The wind speed in Hong Kong can
reach as high as 143mph.
3.68k Pa 184m
2.64k Pa 132m
1.60k Pa 80m
28m
Lateral load: wind load analysis
Multiframe 3D with Lateral
Bending moment Shear force
load applied
Lateral load: wind load analysis
Axial load Deflection
Lateral load: additional mechanism
The additional downward force
from the transfer increases the
effective stance of the building
to resist lateral loads.
Lateral load
Lateral load
Lateral load: Planar trusses
• Transfer truss that wrap
around every 13th story
as the horizontal
bracing were concealed,
thus the horizontal
expression was
removed
• Create planar trusses in
structural steel with the
frames of but two
different geometries
• In the corners of the
towers, we knitted the
columns of the planar
frames into space-
trusses – all within a
reinforced concrete
column
A: Vertical trusses
B: Planar trusses
Lateral load: Columns
Columns:
The shape causes eccentric load.
Off-center loads would cause excessive
stresses in columns.
The solution is that using uniform shear
force mechanism that could counteract
and eliminate the bending.
The system is outstanding of its economy of
material.
Lateral load: Shear walls
• Only a small
portion of the
loads carried to
the service cores
in the lower floors Story 51& 52 Story 38
flows directly to
the foundations.
Story 25 Story 4
Vertical load
The vertical force are transferred through
braces, columns, space trusses ,
transverse truss and diaphragms.
Vertical load
Spire
367./4m
Roof
305.0m
Space Truss: 70th floor
288.0 m
Allows for the vast majority of the
gravitational load to be supported
10kip
at the exterior. By doing so, this
eliminated about half of the dead 51st floor
210.5m
load that there usually is in tall 14kip
buildings (less steel was needed).
38th floor
132.0m
21kip
The center column, rising from
the 25th floor, bears the 25th floor
80m
gravitational load and resists the
overturning moment. 50kip
Ground
floor
Geological map of Hong Kong
Hong Kong:
It is located on the
sedimentary rocks and
volcanic rocks.
Superficial Deposits:
Beach sand, intertidal mud
and sand, and estuarine mud,
clayey silt and sand
Alluvial sand, silt gravel and
colluviums.
Due to its location, it was
designed for twice the live
load that is required in the
United States for this type of
building.
Foundation construction
The foundation was
poured in place, and
it is set on several
caissons.
These caissons were
then surrounded by
concrete
diaphragming walls.
Around the vaults,
the concrete
surrounding the stell
plate is three feet
thick, so this type of
support system for
the base is carried
up to the fourth floor
(Wilson, p.3)
Construction process
man on man
spandrel lassoing
girder
men on
hanging beam
Bibliography
BOOKS:
STRUCTURAL SYSTEMS FOR TALL BUILDINGS
Council on Tall Buildings and Urban Habitat, McGraw Hill, 1995
STEEL, CONCRETE, & COMPOSITE DESIGN OF TALL BUILDINGS, 2nd Edition
Bungale S. Taranath, McGraw Hill, 1997
I. M. PEI
Aileen Reid, Bison Group, 1995
ARTICLES:
SCALING NEW HEIGHT, Architectural Record, Jan. 1991 Vol.179
THE LOGIC OF ECCENTRICITY, Architectural Record, Sep. 1985 Vol. 173
THE BANK OF CHINA, Dr. Larry Bank and Tom Ringelstetter, the University of Wisconsin–
Madison, December 2, 2004
Bibliography
Web Sites:
http://www.bre.polyu.edu.hk/school/WebCompetition05/WDC_2005/47/27.swf
http://www.lera.com/files/Gold%20Medal%2005%20Brochure%20LER.pdf
http://www.archiplanet.org/buildings/Bank_of_China.html
http://www.allaboutskyscrapers.com//sp.bank_of_china.htm
http://www.allaboutskyscrapers.com/sp.bank_of_china.htm
http://forum.skyscraperpage.com/showthread.php?t=152717
http://www.pcfandp.com/a/p/8220/s.html
Bibliography
Web Sites:
http://architectural-world.blogspot.com/2008/05/bank-of-china-tower.html
http://skyscraperpage.com/cities/?buildingID=13
http://books.google.com/books?id=F56YNToJ08wC&pg=PA280&lpg=PA280&dq=ba
nk+of+china+tower+column&source=web&ots=vmRQNuSpxz&sig=aUhMksF9cvnkq
5lGkp2PkUilO6s&hl=en&sa=X&oi=book_result&resnum=7&ct=result#PPA289,M1
Thank you.
