The Niagara Tunnel Facility Project

Cycle de conférences LCH 2013

«The Niagara Tunnel Facility Project»

presented by Helmut Wannenmacher


Tunnel

The Falls Whirlpool

Intake The TBM


The Niagara Tunnel Facility Project «NTFP»

Introduction and Historical Development

The NTFP: Excavation and Support

Economical Lining Design – Passive Pre-stressed Concrete Lining

Constructional Aspects of Passive Pre-stressed Concrete Lining

Lessons learnt ?


Introduction and Historical Development


112°

R6300R7220

Final LiningWaterproofingShotcreteRock Mass 600

Introduction _ NTFP Factbox

Tunnel Length: 10’2 km Diameter external: 14’400 mm Diameter internal: 12’600 mm Lining thickness: 600 mm Flow rate: 500m3/sec capacity : 1,6 TWh Water pressure max.: 13 bar


Introduction

Discharge US: 3’087 m3/secDischarge CAN: 1’824 m3/sec

2013: 2’324 m3/secResidual flow:

¼ of overall energy production of Ontario (CAN) and New York (US)

2’832 m3/sec


Introduction

Construction of a twin tunnel back in the 1950 ties


Introduction

International Control Structure

Ice ControlGate

Gate

NewIntake

ABOVE THE FALLS


Introduction NTFP

Cellular cofferdam with extensive grouting measures to avoid seepage into the open pit


Sir Adam Beck I / II and Pump Storage Reservoir and Generating Station

Introduction NTFP _ Historical Development

1922







Diameter : 15.5 mSupport : 200 mm flanged, half circular I beams with channel lagging

in between







Bench Drilling



Bench Complete





ConcreteForms






The NTFP: Excavation and Support• Limestone• Sandstone• Claystone- Queenston

Shale 60% (swelling)



World’s largest open hard rock TBM>> Big Becky<<

4 m 10 m 14.40 m






The NTFP: Excavation and SupportRock Mass Behaviour


Economical Lining Design – Passive Pre Stressed Concrete Lining


1. Premises of a watertight lining to avoid seepage

2. Postulation of an uncracked lining

3. Economical and sustainable allocation of lining type

General limitations of a passive pre- stressed concrete lining systems are:

Internal Water pressure up to ~ 25 bar for fair rock mass

Good to fair/ (local weak) rock mass conditions

Economical Lining Design


KW

En

zin

ge

rbo

de

n

19

67

KW

Ka

un

ert

al

19

63

KW

Fra

gn

an

t 1

96

8

PS

W D

rake

nsb

erg

19

81

PS

W K

üh

tai 1

97

9

NT

FP

20

13

Lin

tha

l 20

15

UW

ST

B 2

01

2

Lin

tha

l 20

15

OW

DS

T 2

01

2

0

2

4

6

8

10

12

14

16

18

20

0 2 4 6 8 10 12

SLENDERNESS RATIO "SR" [m/m]

TE

NS

ILE

RIN

G F

OR

CE

"Z

" [M

N/m

]

Slenderness ratio and internal water pressure define indirectly the effort of geotechnical measurements for pre- stressing works

Area with high effort of monitoring works

Economical Lining Design _ History


Final LiningContact Grouting

WaterproofingInterface Grouting

Rock massShotcrete

• Rock support (anchors and shotcrete)

Economical Lining Design _ Assembly of layers

• Rock mass grouting

• Installation of membrane PE-VLD

• Installation unreinforced concrete lining

• Pre- stressing final lining – high pressure(gap membrane and shotcrete/ rock mass)

Workflow unreinforced pre-stressed concrete lining

• Contact grouting - low pressure(gap final lining and membrane)


+prock

+pliner

+ r(ro)

tensioncompression

- r(ro)

allow. concrete

1

p o.w

ater

+prock

+pliner

+ r(ro)

tensioncompression

- r(ro)

allow. concrete

2

p o.w

ater

+prock

+pliner

+ r(ro)

tensioncompression

- r(ro)

allow. concrete

Rock mass stress-strainrelationship

3

p o.w

ater

+prock

+pliner

+ r(ro)

tensioncompression

- r(ro)

allow. concrete

4

p o.w

ater

p o.w

ater

+prock

+pliner

+ r(ro)

tensioncompression

- r(ro)

allow. concrete

Waterproofingstress-strainrelationship

p i

5

Phase 1: Initial gap of concrete lining and rock mass

E. L. D._Analytical Graphical Design Method


32

+prock

+pliner

+ r(ro)

tensioncompression

- r(ro)

allow. concrete

1

p o.w

ate

r

+prock

+pliner

+ r(ro)

tensioncompression

- r(ro)

allow. concrete

2

p o.w

ate

r

+prock

+pliner

+ r(ro)

tensioncompression

- r(ro)

allow. concrete


3

p o.w

ate

r

+prock

+pliner

+ r(ro)

tensioncompression

- r(ro)

allow. concrete

4

p o.w

ate

rp o

.wate

r

+prock

+pliner

+ r(ro)

tensioncompression

- r(ro)

allow. concrete


p i

5

Phase 2: Contact grouting (Closure of initial gap - bedding of lining )



33

+prock

+pliner

+ r(ro)

tensioncompression

- r(ro)

allow. concrete

1

p o.w

ater

+prock

+pliner

+ r(ro)

tensioncompression

- r(ro)

allow. concrete

2

p o.w

ater

+prock

+pliner

+ r(ro)

tensioncompression

- r(ro)

allow. concrete


3

p o.w

ater

+prock

+pliner

+ r(ro)

tensioncompression

- r(ro)

allow. concrete

4

p o.w

ater

p o.w

ater

+prock

+pliner

+ r(ro)

tensioncompression

- r(ro)

allow. concrete


p i

5

Phase 3: passive pre-stressing of lining and rock mass



34

+prock

+pliner

+ r(ro)

tensioncompression

- r(ro)

allow. concrete

1

p o.w

ate

r

+prock

+pliner

+ r(ro)

tensioncompression

- r(ro)

allow. concrete

2

p o.w

ate

r

+prock

+pliner

+ r(ro)

tensioncompression

- r(ro)

allow. concrete


3

p o.w

ate

r

+prock

+pliner

+ r(ro)

tensioncompression

- r(ro)

allow. concrete

4

p o.w

ate

rp o

.wate

r

+prock

+pliner

+ r(ro)

tensioncompression

- r(ro)

allow. concrete


p i

5

Phase 4: Pre-stress losses



35

+prock

+pliner

+ r(ro)

tensioncompression

- r(ro)

allow. concreteLining stress-strain

relationship

1

p o.w

ater

+prock

+pliner

+ r(ro)

tensioncompression

- r(ro)


relationship

2

p o.w

ater

+prock

+pliner

+ r(ro)

tensioncompression

- r(ro)


relationship


3

p o.w

ater

+prock

+pliner

+ r(ro)

tensioncompression

- r(ro)


relationship

4

p o.w

ater

p o.w

ater

+prock

+pliner

+ r(ro)

tensioncompression

- r(ro)


relationship


p i

5

Phase 5: Operational phase



Constructional Aspects of Passive Pre-stressed Concrete Lining


Constructional Aspects_Membrane

Specs waterproofing membrane: 3 layers of a modified VLD PE 2 additional layers of PP fleece

Detection of voids with high voltage measurements upon installation


Constructional Aspects_Grout Line


Grouting section: grout barrier

INTA

KE

OU

TL

ET

Total 4 grout lines per section (bay)

Grout section consists of two grout lines

Arch: length ~30,8 m

Invert: length ~14,4 m

Arch

Invert

3,6 to 3,8 m

Constructional Aspects_Grout Line


40

Direct line for filling of an initial gap Improved tube a manchette lines with two rubber sleeves Limitation of grout lines length to 15 m Procedure for pressure tests

Constructional Aspects_Grout Line (lessons learnt)

Cycle de conférences LCH 2013In

take

Low Point

Grouting carrier(mixer, agitator, pumps,cement)

Pre-monitoring carrier

Working carrier (grouting)

Post-monitoring carrier

Grouting Direction

Constructional Aspects_Grouting Setup


S1

Interface Grouting Carrier

Section n+5 Section n+4 Section n+3 Section n+2 Section n+1

Pre-Monitoring Carrier

S6

Working Platform

section n

S5S4S3S2

Post-Monitoring Carrier

• Premises: Monitoring length must cover the area of influence

• Monitoring length NTFP is about 80 -100 m.

Monitoring length = area of influence

Constructional Aspects_comb. Monitoring/ Grouting Concept


Kops-Vallüla, AUT1948internal 2.7m

Drakensberg, S.A.1979-81internal 6.5

Amlach, AUT 1989internal 3.3m

NTFP, CAN2012internal 12.6m

Constructional Aspects_Development of Monitoring Systems


Boundaries Conditions for Development of a Laser System

Accuracy: Accuracy real time < 1 mm Accuracy static 3/10

mm

Traffic: no influence of ongoing traffic

(strict order)

Grout Control System: Interactive control of grout works on basis of deformation measurement

Constructional Aspects_Specifications Monitoring System


FILLINGPHASE

PRESTRESSING PHASE

Constructional Aspects_ Monitoring and Interpretation


IGS 35, radial deformation over time

-2.4

-4.0

-3.5

-3.0

-2.5

-2.0

-1.5

-1.0

-0.5

0.0

0.5

1.0

08.0

9.20

11 0

0:00

10.0

9.20

11 0

0:00

12.0

9.20

11 0

0:00

14.0

9.20

11 0

0:00

16.0

9.20

11 0

0:00

18.0

9.20

11 0

0:00

20.0

9.20

11 0

0:00

22.0

9.20

11 0

0:00

24.0

9.20

11 0

0:00

26.0

9.20

11 0

0:00

28.0

9.20

11 0

0:00

30.0

9.20

11 0

0:00

time / date

rad

ial

def

orm

atio

n [

mm

]

radial strain due to IG: - 3.8 10-4

radial deformation due to IG: - 2.4 mmpoint of time: 27.09.2011

result of strain gauges

result of strain gaugesFILLINGPHASE

PRE-STRESSINGPHASE

S2 S1

IGS 32 IGS 33 IGS 34 IGS 35 IGS 36 IGS 37 IGS 38

S4S1 S3

Development of radial deformation due neighboring grouting works



Section140, differential deformation (developed view)

Date/Time: 02.04.2012 20:40

Ovalisation: 4.00 mm

m. rad. Deformation -1.38 mm




Date/Time: 02.04.2012 23:39






Date/Time: 03.04.2012 00:40






Date/Time: 03.04.2012 01:10






Date/Time: 03.04.2012 01:45






Date/Time: 03.04.2012 02:15






Date/Time: 03.04.2012 02:46






Date/Time: 03.04.2012 03:12






Date/Time: 03.04.2012 03:40






Date/Time: 03.04.2012 04:24






Date/Time: 03.04.2012 04:57






Date/Time: 03.04.2012 05:30



Extensometer 5-6

2

4

6

8 7

5

3

1

Lining 03.04.2012 05:34

interpolation of splines is based on cubic spline interpolation method





-5.0

-4.5

-4.0

-3.5

-3.0

-2.5

-2.0

-1.5

-1.0

-0.5

0.00 5 10 15 20 25

rad

ial d

efo

rmat

ion

[m

m]

pre-stress pressure [bar]

data

behaviour of final lining - average

behaviour of final lining - boundary range

behaviour of final lining - boundary range +/- 25%

0%

20%

40%

60%

80%

100%

0%

20%

40%

60%

80%

100%



0.0

5.0

10.0

15.0

20.0

25.0

30.009

.09

.12

15:1

5:0

0

09.0

9.1

2 15

:30:

00

09.0

9.1

2 15

:45:

00

09.0

9.1

2 16

:00:

00

09.0

9.1

2 16

:15:

00

09.0

9.1

2 16

:30:

00

09.0

9.1

2 16

:45:

00

09.0

9.1

2 17

:00:

00

09.0

9.1

2 17

:15:

00

09.0

9.1

2 17

:30:

00

09.0

9.1

2 17

:45:

00

09.0

9.1

2 18

:00:

00

09.0

9.1

2 18

:15:

00

09.0

9.1

2 18

:30:

00

09.0

9.1

2 18

:45:

00

09.0

9.1

2 19

:00:

00

09.0

9.1

2 19

:15:

00

09.0

9.1

2 19

:30:

00

09.0

9.1

2 19

:45:

00

09.0

9.1

2 20

:00:

00

09.0

9.1

2 20

:15:

00

09.0

9.1

2 20

:30:

00

09.0

9.1

2 20

:45:

00

09.0

9.1

2 21

:00:

00

Pre

ssu

re [

bar

]F

low

rat

e [l

/min

]

date / time

Pressure

Pressure Test

flow rate

strain gauge



-2.5

-2.0

-1.5

-1.0

-0.5

0.0

08.0

9.2

012

06.

00

08.0

9.2

012

09.

00

08.0

9.2

012

12.

00

08.0

9.2

012

15.

00

08.0

9.2

012

18.

00

08.0

9.2

012

21.

00

09.0

9.2

012

00.

00

09.0

9.2

012

03.

00

09.0

9.2

012

06.

00

09.0

9.2

012

09.

00

09.0

9.2

012

12.

00

09.0

9.2

012

15.

00

09.0

9.2

012

18.

00

09.0

9.2

012

21.

00

10.0

9.2

012

00.

00

rad

ial

de

form

atio

n [

mm

]

date /time

Mobile Deformation Monitoring

Strain Gauge

09.09.2012 20:46

-2.2

8

mm

mm

Date / Time

Ovalisation

Radial deformation

Mobile Monitoring Results due to IG

Start Value due toContact Groutingand Filling Phase




Observation of pre-stressing losses before watering up Antithesis of doctrine , to be investigated by a phd study !!!!!!!!


Lessons learnt ?


• Effective und risk minized operation of pre-stressing works due to dection in time (spalling and overstressing may lead to damage of structure and personal)

• Full scale documentation and detection of area with insufficient pre-stressing (Intervention)

• Amortisation of initial cost due to shortage of time for pre-stressing works.• System is now fully developed (after 10 km) and can be rented !!!!!!!!!

ContraContraProPro

(Higher initial investment for monitoring system)

Qualified und experienced personal necessary for set up and monitoring

Intense work preparation

(Higher initial investment for monitoring system)

Qualified und experienced personal necessary for set up and monitoring

Intense work preparation

Pre-stressed pressure tunnels work! Combined grouting / deformation (full

face) is the key to success Full face monitoring is valuable for

geotechnical monitoring and data interpretation and documentation for owner

In time decision making , no delays (costs)

Pre-stressed pressure tunnels work! Combined grouting / deformation (full

face) is the key to success Full face monitoring is valuable for

geotechnical monitoring and data interpretation and documentation for owner

In time decision making , no delays (costs)

Conclusion

Conclusion

Lessons learnt


Operation

Supervisor

Shift Engineer

Foreman

Technicans Pumps

Operator Pumps

Design & Monitoring

P.P-S.C.L.

Experienced design team

Geotechnical Eng. on site

Mechatronics

Mechatronics Electricians

Software Engineers

Lessons learnt

further contact : [email protected]

Thanks for your audience.

Engineering

The Niagara Tunnel Facility Project