BIRTH, DEVELOPMENT AND FUTURE OF EXTRADOSED BRIDGES

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BIRTH, DEVELOPMENT AND FUTURE OF

EXTRADOSED BRIDGES

AKIO KASUGA

SUMITOMO MITSUI CONSTRUCTIONJAPAN

Birth

2

Mathivat’s Paper (FIP Note,1988)

Seminar in BUT / Budapest / 19 September 2019 SUMITOMO MISTUI CONSTRUCTION

Span Length VS Average Depth of Concrete

SUMITOMO MISTUI CONSTRUCTIONSeminar in BUT / Budapest / 19 September 2019

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Span Length VS Tendon Weight


■ エクストラドーズド橋

▲ 斜張橋

◆ 箱桁橋

Cost Comparison


4

Odawara Blueway Bridge (1994)


Development of Saddle & Extradosed Cable System


✓ No saddle system was available.✓ New saddle system fixed at both ends was developed.✓ Epoxy coated strand was used as extradosed cables.

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HDR

Development of High Damping Rubber Damper


✓ After Odawara, HDR damper was widely used all over the world.

LD : Logarithmic Decrement

kopt k

LD

LDmax

Development of High Damping Rubber Damper

w/o Damper (LD = 0.002)

w/ Dampers 1st Mode (2.57Hz, LD = 0.068)

2nd Mode (5.14Hz, LD = 0.062)

3rd Mode (7.71Hz, LD = 0.061)


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Development

Tsukuhara Bridge (1997)


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Δϭ ≤ 50N/mm2

Fretting Fatigue Test of Saddle


Ibigawa Bridge (2001)


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Fabrication Yard（100,000m2）

Lifting of Stell Girder（2000ｔ）

Segment（400ｔ）

Lifting Traveler

Construction of Ibigawa Bridge


Shin-Meisei Bridge (2004)


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Horizontal Tension ：SteelVertical Compression：Steel & Concrete

Development of Steel Box Anchorage for Pylon

Concrete after Completion


Himi Bridge (2004, Corrugated Steel Web)


10

12950

85002225 2225

4000

Steel Diaphragm of Himi Bridge for Corrugated Steel Web

Stay Cable Anchorage in Girder


Loading

Bearing Bram

Girder

Extradosed Cable

Half Size Model Test


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0

500

1000

1500

2000

2500

3000

3500

0 50 100 150 200 250 300 350

DISPLACEMENT (mm)

LO

AD

(kN

)

Non-linear 2D Frame Analysis

Non-linear 3D FEM Analysis

Test Results

Test Results


Fudo Bridge (2010, Composite Truss)


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Test for Truss Connection (Half Size)

2000

425

100014

25

1000

1160

34003700

500

500

350

14221232

2873

1701240

200

150300 320

250

2400

図-5 実験供試体構造図

反

力

壁

載荷荷重

スライドレール

斜材張力

引張材圧縮材

Stay Cable Force

Horizontal Force

TensionCompression


孔あき鋼板ジベル

十字リブ

スパイラル筋

コンクリート充填部

Rib Plate

Concrete Dowel

Spiral Bar

0

100

200

300

400

500

600

-60 -50 -40 -30 -20 -10 0

曲げモーメント　(kN･m)

水平載荷荷重　(kN)

圧縮側引張側計算値回転バネ

　2500kNm/rad

計算値　剛結

Secondary Bending Moment (kNm)

Ho

rizo

nta

l Lo

ad (

kN)

Compression Member Tension Member

Rigid Connection

Rotational Spring

(2500kNm/rad)

Perforated Dowell Connection


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コンクリート充填部

ねじふし鉄筋

定着プレート

ナット

ナット

NutBearing Plate

Re-bar

Nut

0

100

200

300

400

500

600

700

-60 -50 -40 -30 -20 -10 0

鋼管曲げモーメント　(kN･m)

水平載荷荷重　(kN)

計算値回転バネ1000kNm/rad

計算値　剛結

圧縮側引張側Compression Member Tension Member

Rotational Spring

(1000kNm/rad)

Rigid Connection

Secondary Bending Moment (kNm)

Ho

rizo

nta

l Lo

ad (

kN)

Re-bar Connection



EDB with Composite Truss Girder

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Bridge Type Axial Force

(A) Girder Bridge (max.span : 43m)

Average thickness of concrete t=370mm

1380kN

(B) Extradosed Bridge (max.span : 120m)


1590kN

Axial Forces in Truss


Bridge Type Axial Force

(C) Extradosed Bridge (max.span : 250m)


1420kN

(D) Cable Stayed Bridge (max.span : 320m)


1590kN


Axial Forces in Truss

Composite truss can make axial forces constant in all

span range!

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Mukogawa Bridge (2016)

Mukogawa Bridge (2016)


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✓ Structural Behavior of Butterfly Web = Double Warren Truss

Structural Behavior of Butterfly Web Bridge


Construction of Mukogawa Bridge


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Basic design (101 segments)

Detail design (54 segments)

✓ Number of days required for cantilever construction reduced.✓ The weight of superstructure was reduced up to 20% from the basic design.

Effects of the Extradosed Structure with Butterfly Webs

15 segments for cantilever erection 14 segments for cantilever erection

8 segments for cantilever erection 8 segments for cantilever erection


Natural periodLongitudinal

(temporary)

Transverse

(temporary)

Basic plan (s) 1.59 2.90

Detail design (s) 2.29 3.82

✓ Total weight of super- and sub-structures was reduced by about 35%.

Basic design

Detail design


P1P4 P3 P2

D≦5.0m


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Bending moment at the bottom of the piers

Ratios of flexural rigidity (EI) to height (h) of the piers

Improved seismic performance

0.0E+00

5.0E+05

1.0E+06

1.5E+06

2.0E+06

2.5E+06

P4 P3 P2 P1

Basic plan

Detail design

M(k

N･m

)

0.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

8.0

9.0

P4 P3 P2 P1

Basic planDetail design

（※）Ratio of each pier w ith P3 as 1.0

EI/h


SUMITOMO MISTUI CONSTRUCTION

Basic designBasic design

Seminar in BUT / Budapest / 19 September 2019

2.0m

Construction of Piers


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Construction of Superstructure



Tower Detail

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Mukogawa Bridge


Specifications for CSB & EDB by JPCI

(2009) (2012)


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Strand System

Wire System

70

ΔσL (N/mm2)

0.4 fpu

130100

0.6 fpu

fpa Strand System

Wire System

70

ΔσL (N/mm2)

0.4 fpu

130100

0.6 fpu

fpa

Allowable Stress of Stay Cables



EDBs have been extended after Odawara

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US Mission for EDB

2000

1750

3000

3000

200200100 1000 1000 100

200200

3000

325

1100

325

1750

Development of Cable Stay Anchorage (Concrete Type)

Bar φ32mm


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1300

625

1450

3400

Steel plate t=100mm

鉄筋ジベルD25

Bar φ32mm

Development of Cable Stay Anchorage (Single Steel Plate Type)


20

00

13658601365

10

00

3590

Steel plate t=40mm

Re-bar D25

Development of Cable Stay Anchorage (Double Steel Plate Type)


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2000

1365

1000

3590

Stud φ19

Development of Cable Stay Anchorage (Advanced Steel Plate Type)

Steel plate t=40mm


New Saddle (Chao Phraya River Crossing Bridge)


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Future

Future Application of Butterfly Web Bridge

500m multi-span cable-stayed type


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500m multi-span extradosed type


✓30% Opening leads to good performance in wind tunnel test.


(30% opening)

Girder Configuration

Wind Tunnel test


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- Girder Heaving 1st Mode : 3.13 sec- Girder Torsional 1st Mode : 1.47 sec- Logarithmic Decrement : 0.004

Photo : Kyoto University

Wind Tunnel Test Setup (1/100)


Conventional Web Butterfly Web

No vortex shedding

Flexural Vibration Test


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Torsional Vibration : 2 degrees25m-sec

Torsional Flutter : 60m-sec

Torsional Vibration : 1 degrees25m-sec

Torsional Flutter : 90m-sec

Conventional Web Butterfly Web

Torsional Vibration Test


Conventional Box Girder


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Butterfly Web Girder


Stay Cable Stress Change due to Live Load

✓ Structural behavior can be simulated by NLFEM


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___________________________________________________________

CSB EDB ___________________________________________________________

Concrete Girder m3 48900 43700 Pylon m3 18500 14400

Rebar ton 15960 13410 Prestressing steel ton 259 261 Stay cables ton 6030 6300 ___________________________________________________________

Comparison of Material Quantities


800m-span hybrid cable supported bridge (Extradosed + Suspension)



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Unit Case 1 Case 3

Stay Cable t 2,873 2,536

Main Cable t 11,170 5,639

Hanger t 55 29

PC tendon t 541 505

Total t 14,639 8,709

Comparison of Material Quantities


Concluding Remarks

➢ The extradosed bridge enables engineers to apply consistent design principles to cable-stayed bridges and ordinary girder bridges.

➢ Proposed stay cable design method is effective in consistent design approach.

➢ The extradosed bridge greatly increases the degree of freedom for the design of cable-supported structures.


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Thank you for your attention

Documents

BIRTH, DEVELOPMENT AND FUTURE OF EXTRADOSED BRIDGES