construction of bifurcation section of underground ... · pdf fileparis–15 november 2017...

PARIS– 15 November 2017

Construction of bifurcation section of

underground expressway underneath

residential area,

Application of enlargement/widening

technology of TBM tunnel

Akihiro Nishimori, OBAYASHI Co.

Manager, Shield Tunnel Engineering Dept.

[email protected]

Construction of Bifurcation – Akihiro Nishimori shutoko Obayashi Okumura Seibu


Stakeholders

Kazuhito Uchiumi, Deputy Manager, Metropolitan Expressway Co.

[email protected]

Kenta Matshbara, Construction Manager, OBAYASHI Co.

[email protected]



Tokyo Japan



Yokohama North Line

8.8km



Dual TBM for 5.5km Length

4nos Ramp Tunnels

Dual TBM for 5.5km length, mostly underneath Residential Area

4nos Ramp Tunnels, Bifurcation of road tunnel required at connection



● Long Section of Bifurcation

20m width Bifurcation Underneath Residential Area⇒ Construction without open cut method (i.e. tunneling work)⇒ Prevent adverse impact on residential area, with controlling settlement

Bifurcation (20m width, 200m length) x4

Main Shield Tunnel x2Ramp Shield Tunnel x4

Ground Sample

Alluvium

Loam Clay, Diluvium

Kazusa Silt(Quaternary Deposit)

Kazusa Sand(Quaternary Deposit)

Cover 28～54m

Main Shield TunnelBifurcation

Ramp Shield Tunnel


● Plan of Bifurcation


Soft Ground

Conventional NATM

Water Seepage

Ground Settlement

Ground Disp.

Permeable Layer (LDPR)

Large Dia. Pipe Roof Φ1.2m

High RigidityWater Tight


Supported by LDPR


LDPR Shaft by Open Cut

Land acquisition

LDPR Shaft by ESTM

(ESTM)

Enlargement Shield

Tunnelling Machine



Thrust Jacking

Enlargement Shield Tunnelling Machine (ESTM)

Enlarged Segment

Launching Shaft

Arc Shaped Rectangular EPB 11x3m



①-① ④-④

12025

11388

拡大

シールド

大口径

パイプルーフΦ1200

本線

シールド

拡幅終端部拡大シールド終端部

Max. Enlarged Section Mid. Enlarged Section LDPR Shaft by ESTM

①-① ④-④

12025

11388

拡大

シールド

大口径


本線

シールド


①-① ④-④

12025

11388

拡大

シールド

大口径


本線

シールド


ESTMLDPRLDPR

楕円形躯体（t=800）

101.5m

楕円形躯体（t=600）

40.0m

楕円形

躯体

（t=500）

5.0m

ランプシールド

到達部拡大

シールド

11.0m

Main Shield Tunnel

Bifurcation



Grouting

Main Shield

Tunnel

Grouting for

ESTM

Grouting for

End Point

Grouting for Intermediate Wall

(Risk mitigation for seepage)

STEP1 : Grouting Work (Preparation for Bifurcation Construction)

No disruption of Main

Tunnelling Work



ESTM

for Shaft of LDPR (Large Dia. Pipe Roof)

STEP2 : ESTM (Enlargement Shield Tunnelling Machine)

Shat &Entrance ESTM Launching ESTM Driving ESTM Arrival



LDPR（27Nos／Ramp）

STEP3 : LDPR (Large Dia. Pipe Roof φ1200)

LDPR Shaft LDPR Bor. Machine Thrusting Jack Thrusting Stage



パイプルーフ間薬液注入

Grouting Work

(low pressure method)

Grouting

STEP4 : Grouting Between LDPR

Drilling Work Grouting Work



Concrete Lining

Widening Excavation

STEP5 : Widening Excavation & Concrete Lining

Segment Removal Excavation Structural Work Concrete Lining



Bifurcation Lining

STEP6 : Completion of Bifurcation



Conclusion

1) Bifurcation with combination of ESTM & LDPR

2) No disruption and acquisition of surface ground

3) Minimize ground displacement

4) Applicable urban Highway/Railway projects



Thank you for your attention


construction of bifurcation section of underground ... · pdf fileparis–15 november 2017...

Documents