evolution of bridge technology - Structural Engineering Institute

ASCE/SEI Workshop, Washington DC, Feb.2008
EVOLUTION OF
BRIDGE TECHNOLOGY
BY
MAN-CHUNG TANG, Chairman of the Board
Presented by
Tom Ho, Vice President
T.Y. Lin International

1. What has been the most important factor in the
evolution of bridge technology?
2. Would the Romans and the Egyptians be able
to build our bridges if they had the
construction materials of today?

Evolution:
Human beings started building bridges
many thousand years ago.
What made our modern bridges different
from the ancient ones?

First of all,
What are our bridges made up of?
Let us look at the
bridges we have today.

In the several thousand years since we started
building bridges, we have built only
FOUR TYPES OF BRIDGES

In the several thousand years since we started
building bridges, we have built only
FOUR TYPES OF BRIDGES
Girder bridges
Arch bridges
Suspension bridges
Cable-stayed bridges

Extradosed Bridge is a combination of
girder bridge and cable-stayed bridge

We can have other combinations too
Partially cable-supported girder bridges.

Franz Dishcinger proposed this
combination of
cable-stayed and suspension bridge

But, still only these four basic types.

All four types
of bridges have
existed for
millenniums!
CONT. BEAM
SUSPENSION
STRESS RIBBON
CABLE-STAYED
GIRDER
They were not as
sophisticated.
But, conceptually
correct nevertheless!

All four types
of bridge have
existed for
millenniums!
CONT. BEAM
SUSPENSION
STRESS RIBBON
CABLE-STAYED
GIRDER
They build
them
Intuitively
Even before
we gave them
They were not as
sophisticated. a name.
But, conceptually
correct
nevertheless!

All four types
of bridge have
existed for
millenniums!
CONT. BEAM
SUSPENSION
STRESS RIBBON
GIRDER
They used
Construction materials
available CABLE-STAYED naturally!
Wood, vines, stone, ropes,
They were not as
sophisticated. etc.
But, conceptually
correct
nevertheless!

Sad to admit,
In the last few thousand years,
We have NOT invented any new bridge type.

Because we have not invented anything
It is an evolution
Not any revolution.

Because we have not invented anything
It is an evolution
Not any revolution.
But, our bridges today are
Bigger, stronger, more sophisticated, more durable
and, more predictable.

Today’s
bridges
Bigger,
stronger,
more
sophisticated,
and
more durable
CRAIGELLACHIE, 1815

What affects the evolution of bridge technology?

What affect the evolution of bridge technology?
Science - structural theories
Construction equipment
Construction material

Look at these old, old structures

What affect the evolution of bridge technology?
?
Structural theories
Construction equipment
Construction material

What affect the evolution of bridge technology?
Structural theories
Construction equipment
Construction material
?

They did it empirically!
Structural theories
Construction equipment
Construction material

They did it empirically!
Pyramid of Dozer
2750BC
60
40
20
0
1st
Qtr
3rd
Qtr
Great Pyramid of Gaza
2550 BC
West
North

They did it empirically!
Structural theories
Construction equipment
Construction material
They made it work, somehow!

Structural theories
Construction equipment
Construction material
Material has been the most
important factor in the evolution!

Creation of a bridge - A Flow Chart

A Flow Chart

Two Dominating Materials in the
History of Bridge Construction are:
Stone
&
Steel
Dominating influence

2000 BC
Two main eras in bridge evolution:
Arch Era
2000BC– 1850AD
Almost 4000 years
Contemporary Era
1850AD - now
Only about 160 years
Roman
Empire
Stone
&
Steel
Arch Era
1850 AD
Contemporary Era
2008 AD

ARCH ERA
Stone

Up to two hundred years ago,
the only construction material available was STONE.
STONE can take high compression,
but very little tension.

Arch is the only bridge type that
does not require tensile capacity of the material

Arch is the only bridge type that
does not require tensile capacity of the material

The Romans built
many spectacular
arch bridges

The Romans built
many spectacular
arch bridges
Over 2000 years ago!

The Romans built
many spectacular
arch bridges
The Roman arches
are all semi-circular

37m
Zhaozhou Bridge
7m
37m
A Roman Arch
Zhaozhou Bridge, China
Span 37m, Rise 7m. Built 600AD
18.5m
The first
non-semi-circular arch bridge.

Semi-circular vs Segmental
18.5m
7m

The Romans were really masters on stone arches!

The Romans were really masters on stone arches!
But, for almost one and a half millennia
after the Romans,
nothing new happened!

Then came the
Contemporary Era
From 1850 until now

Contemporary Era
From 1850 until now
Only about 160 years.
But there were more bridges built in these 160 years
than the 4000 years before it.

Contemporary Era
From 1850 until now
Iron & Steel

There was a transition period that we had
IRON as construction material.
Iron is much stronger than stone, but its
tensile capacity is still very limited.

There was a transition period that we had
IRON as construction material.
Iron is much stronger than stone, but its
tensile capacity is still very limited.
We may categorize iron as a primitive
form of steel, as far as construction
material is concerned.

The Chinese started building iron chain
suspension bridges around 600 AD

A
suspension bridge
in Tibet

A bridge in Tibet

A bridge in Tibet

Iron arch bridges was
popular for a period of time
Dom Luis I Bridge
By Gustav Eiffel and Th. Seyrig,
1885, span = 172m
Coalbrookdale Bridge,
Span 30.5m
By Thomas Pritchard, 1779

Menai Bridge – the first major suspension Bridge
Designed by Thomas Telford, span = 176m
based on a patent by James Findley, completed in 1826.
With iron eye bar chains as main cable.

Menai Bridge – the first major suspension Bridge
Designed by Thomas Telford, span = 176m
B
based on a patent by James Findley, completed in 1826.
With iron eye bar chains as main cable.

Steel
Mass production processes were introduced in the mid 19th
century

Steel
Mass production processes were introduced in the mid 19th
century
It changed the entire landscape of bridge construction

Steel
Mass production processes were introduced in the mid 19th
century
It changed the entire landscape of bridge construction
Steel plates used for girders – boxes and trusses
Steel bars for concrete reinforcement
Steel cold drawn wires for cables
Steel wires for prestressing

Steel
Mass production processes were introduced in the mid 19th
century
Three landmark steel bridge structures before the 20 th century:
1. St. Louis Bridge by James Eads, 1874
2. Brooklyn Bridge by the Roeblings, 1883
3. Firth of Forth Bridge by John Fowler and Benj. Baker, 1889

The St Louis Bridge over the Mississippi.
Completed 1874, Spans 153m + 158.5m + 153m
Designed by James Eads

The Brooklyn Bridge, New York City
Completed 1883, Span 486m.
Designed by John and Washington Roebling

The Firth of Forth Rail Bridge, Scotland.
Completed 1889, Span 521m.
Designed by John Fowler and Benjamin Baker

Then came
A tale of three bridges,
in early 1900s……………………
Hell Gate Bridge,
Sydney Harbor Bridge
Bayonne Bridge
The Hell Gate Bridge in New York
by Gustav Lindenthal. Span = 298m.
Completed in 1916.
Bayonne Bridge in NY.
By Othmar Ammann
Span = 503.6m
Constr. 1928 - 1931
Sydney Harbor Bridge.
Span = 503m
by Ralph Freemann,
Const. 1924 - 1932.

Lupu, China, 2004
Span = 550m
New River Gorge, USA, 1978
Span = 518.3m

Competition of Span Lengths
Span Year
Hell Gate, NY Gustav Lindenthal 298 1916
Sydney Harbor Ralph Freemann 503 1932
Bayonne, NY Othmar Amman 503.6 1931
New River Gorge, WV Michael Bakers 518.3 1978
Lupu, Shanghai Lin Yuan Pui 550 2004
Caotienmen, Chongqing 552 2008

S p an Leng ths ( m )
600
500
400
300
200
100
0
St. Louis
Pia Maria
Competition of Arch Span Length
Garabit
Luis I
Hellgate
Sydney Harbor
Bayonne
1850 1900 1950
Year
2000 2050
New River Gorge
Lupu
Caotienmen

Long span suspension bridges
became possible only after high strength wire
was available.

High Strength Steel Wire for Suspension Bridges
Some landmark suspension bridges:
Brooklyn 486m, 1883
George Washington 1067m, 1931
Golden Gate 1280m, 1937
Verranzano Narrows 1298m, 1964
Humber 1410m, 1981
Storebelt 1624m, 1998
Akashi Kaikyo 1991m, 2000

Golden Gate 1280m, 1937
Verranzano Narrows 1298m, 1964
Humber 1410m, 1981

Storebelt 1624m 1998
Akashi 1991m 2000

Span Length (m)
2500
2000
1500
1000
500
0
Longest Suspension Bridge Spans
Menai
Sarine Valley
Brooklyn
G. Washington
Golden Gate
1800 1850 1900 1950 2000 2050
Year
Verranzano
Humber
Storebelt Akashi

Span Length (m)
2500
2000
1500
1000
500
0
Longest Suspension Bridge Spans
Iron Steel
Menai
Sarine Valley
Brooklyn
G. Washington
Golden Gate
1800 1850 1900 1950 2000 2050
Year
Verranzano
Humber
Storebelt Akashi

The two giants:
Messina 3,300m
Gibraltar 5,000m

High Strength Wires
also made cable-stayed bridges popular

High Strength Wires
also made cable-stayed bridges popular
Because of the sag, cables must be stressed to a
high force to be effective.
Consequently, cables must be highly stressed.

High Strength Wires
also made cable-stayed bridges popular
Because of the sag, cables must be stressed to a
high force to be effective.
Consequently, cables must be highly stressed.
This means, cable wires must be very high strength.

Three World Record Spans within 60km.
(Dusseldorf & Duisburg)
Theodore Heuss 260m 1957
Knie 320m 1970
Neuenkamp 350m 1971

Span Lengths (m)
1200
1000
800
600
400
200
0
Longest Cable-Stayed Bridge Spans
Stromsund
Th. Heuss
Leverkusen
Knie
Neuenkamp
Sain Nazaire
Annacis
1950 1960 1970 1980 1990 2000 2010 2020
Year
Yangpu Normandy
Tatara
Sutong

High Strength Steel
also made prestressed concrete bridges possible

High Strength Steel
also made prestressed concrete bridges possible
Without high strength steel, prestressing is
not effective.

Two Significant Prestressed Concrete
Box Girder Bridges
Bendorf Bridge
Span 208m, 1962
Second Shibanpo Bridge
Span 330m, 2006

SPAN LENGTH (m)
跨度
350
300
250
200
150
100
50
0
CONCRETE GIRDER BRIDGES
1940 1950 1960 1970 1980 1990 2000 2010
YEAR OF COMPLETION
混凝土連續剛構
年份
“Concept of Structures“ by Man-Chung Tang,, 2003

SPAN LENGTH (m )
跨度
350
300
250
200
150
100
50
0
Milestone Segmental Bridges
Bendorf
Worms
Balduinstein
Koror
1940 1950 1960 1970 1980 1990 2000 2010
YEAR
混凝土連續剛構
Shibanpo
Stolmasundet
Gateway
“Concept of Structures“ by Man-Chung Tang,, 2003

跨度
350
SPAN LENGTH (m)
300
250
200
150
100
50
0
LONGEST STEEL BOX GIRDER BRIDGES
1950 1960 1970 1980 1990 2000 2010
YEAR OF COMPLETION
年份
钢箱
“Concept of Structures“ by Man-Chung Tang,, 2003

Effect of Materials on Evolution of Bridge Technology
Wood - timber bridges, short spans
Stone - arch bridges, longer spans
Iron - early suspension bridges
Steel - long span girder bridges
Steel wires - long span suspension bridges
- cable-stayed bridges
- prestressed concrete bridges

Evolution:
1. What was the most important factor in
the evolution in bridges?
2. Would the Romans and the Egyptians
be able to build our bridges if they had
the construction materials we have?

Evolution:
1. What was the most important factor in
the evolution in bridges?
2. Would the Romans and the Egyptians
be able to build our bridges if they had
the construction materials we have?
Obviously, no one knows. But let us take an example.

Aerodynamics

Aerodynamics
Most early suspension bridges were failed by wind.
Around 1800, James Findley patented the stiffened
suspension bridge.
Most of those bridges were destroyed by wind.

Aerodynamics
Most early suspension bridges were failed by wind.
Around 1800, James Findley patented the stiffened
suspension bridge.
Most of those bridges were destroyed by wind.
Around 1870, John Roebling installed inclined cables in
Wheeling Bridge to help mitigate wind vibration
problems. It worked!
He found a solution in less than 70 years.

Aerodynamics
Most early suspension bridges were failed by wind.
Around 1800, James Findley patented the stiffened
suspension bridge.
Most of those bridges were destroyed by wind.
Around 1870, John Roebling installed inclined cables in
Wheeling Bridge to help mitigate wind vibration
problems. It worked!
He found a solution in less than 70 years.

Engineering is an art, not a science!
Most engineering solutions came before the theory.

Engineering is an art, not a science!
Most engineering solutions came before the theory.
And,
Looking at how the Egyptians, the Romans and the
Chinese built their spectacular structures,
Structural theories and modern equipments do not
seem that important.

Engineering is an art, not a science!
Most engineering solutions came before the theory.
To answer my second question, I may dare say that
given the materials we have today,
The Romans and the Egyptians would most
probably be able to build our bridges too!

But
Evolution of bridge technology can only happen
if we have the opportunity to build bridges.

But
Evolution of bridge technology can only happen
if we have the opportunity to build bridges.
Two pre-requisites determine if a bridge will be built:
1. Affordability
2. Necessity

But
Evolution of bridge technology can only happen
if we have the opportunity to build bridges.
Two pre-requisites determine if a bridge will be built:
1. Affordability
2. Necessity
Cost vs. Value

COSTS:
Planning
Right of Way
Construction
Maintenance
Others
YES!
<
=
>
NO!
VALUE:
Functional value
Community Value
Political Value
Aesthetic Value
Others

COSTS:
Planning
Right of Way
Construction
Maintenance
Others
<
=
VALUE:
Functional value
Community Value
Political Value
Aesthetic Value
Others

COSTS:
Planning
Right of Way
Construction
Maintenance
Related Others to
Construction
cost index.
<
=
VALUE:
Functional value
Community Value
Related to the
Political Living Value Standard.
Aesthetic Value
Others

As our society progresses,
the living standard usually increases
faster than the construction costs.
COSTS:
Planning
Right of Way
Construction
Maintenance
Related Others to
Construction
cost index.
<
=
VALUE:
Functional value
Community Value
Related to the
Political Living Value Standard.
Aesthetic Value
Others

As our society progresses,
the living standard usually increases
faster than the construction costs.
That means,
some bridges we can not afford today
may become affordable tomorrow.

As our society progresses,
the living standard usually increases
faster than the construction costs.
That means,
some bridges we can not afford today
may become affordable tomorrow.
That also means, we will be building bigger
and bigger bridges, as time goes by!

As our society progresses,
the living standard usually increases
faster than the construction costs.
That means,
some bridges we can not afford today
may become affordable tomorrow.
That also means, we will be building bigger
and bigger bridges, as time goes by!
Good news for us bridge engineers!

But
Evolution of bridge technology can only happen
if we have the opportunity to build bridges.
Two pre-requisites determine if a bridge will be built:
1. Affordability
2. Necessity
When do we need a new bridge?

But
Evolution of bridge technology can only happen
if we have the opportunity to build bridges.
Periods with Great Opportunities:
The expansion of the Roman Empire
The industrial revolution
The re-construction after World War II
Currently, in China, India and other developing countries.

But
Evolution of bridge technology can only happen
if we have the opportunity to build bridges.
Periods with Great Opportunities:
The expansion of the Roman Empire - Stone Arch Bridges
The industrial revolution - Steel production
The re-construction after World War II
Currently, in China, India and other developing countries.

But
Evolution of bridge technology can only happen
if we have the opportunity to build bridges.
The Expansion of the Roman Empire - Stone Arch Bridges
The industrial revolution - Steel production
The re-construction after World War II -
cable-stayed bridges, orthotropic decks, prestressed
concrete bridges, composite decks

But
Evolution of bridge technology can only happen
if we have the opportunity to build bridges.
Periods with Great Opportunities:
The Expansion of the Roman Empire - Stone Arch Bridges
The industrial revolution - Steel production
The re-construction after World War II -
cable-stayed bridges, orthotropic decks, prestressed
concrete bridges, composite decks
Currently, in China, India and other developing countries.?

But
Evolution of bridge technology can only happen
if we have the opportunity to build bridges.
Periods with Great Opportunities:
The Expansion of the Roman Empire - Stone Arch Bridges
The industrial revolution - Steel production
The re-construction after World War II -
cable-stayed bridges, orthotropic decks, prestressed
concrete bridges, composite decks
Currently, in China, India and other developing countries.
We will see !

Tot al Lengt h ( km)
90000
80000
70000
60000
50000
40000
30000
20000
10000
0
Starting Year
USA – 1956
China – 1987
FREEWAY CONSTRUCTI ON
USA
Interstate Only
Ca. 1975
China vs. USA
2007
China
Total
0 10 20 30 40 50
Year s af t er St ar t

Tot al Lengt h ( km)
90000
80000
70000
60000
50000
40000
30000
20000
10000
0
Starting Year
USA – 1956
China – 1987
FREEWAY CONSTRUCTI ON
USA
Interstate Only
2007
China
Total
0 10 20 30 40 50
Year s af t er St ar t
苏通大桥第五次专家论坛 正交异性板钢桥面的一个新构思 林同棪国际 -邓文中

My last question today:
Currently, we have new materials with very
high strength: composites, HPC, etc.
What kind of evolution in bridge technology
will they bring us ?

My last question today:
Currently, we have new materials with very
high strength: composites, HPC, etc.
What kind of evolution in bridge technology
will they bring us ?
They say,
We can predict the future based on the past!

My last question today:
Currently, we have new materials with very
high strength: composites, HPC, etc.
For Example…….
What kind of evolution in bridge technology
will they bring us ?
They say,
We can predict the future based on the past!

History may offer good
hints for the future!
IN RUSSIA

Here is a historic
record of HAIR.
HAIRY
IN RUSSIA
BALD HAIRY
BALD HAIRY BALD HAIRY BALD
Obviously the next President must be a hairy one!!

Let us forget about the
hairs …..
Currently, we have new materials with very
high strength: composites, HPC, etc.
What kind of evolution in bridge technology
will they bring us ?
We know they will definitely enhance the bridge
performance, but would they bring out now bridge
types?

Coming back to
My last question today:
Currently, we have new materials with very
high strength: composites, HPC, etc.
What kind of evolution in bridge technology
will they bring us ?
Well, this is the homework for the future
generations of engineer,
because I still have no idea!

Thank You!