aspects of pressure tunnel lining with special focus on pre-stressed pressure tunnels
TRANSCRIPT
HYDRO 2013 – Tunnels and Underground Works
«Aspects of pressure tunnel lining with special focus on pre-stressed pressure tunnels»
byHelmut Wannenmacher,
Michael Bauert and Andreas Heizmann
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Background
Rock Hydraulical Conditions
Geological Conditions
EconomicalAspects
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Semi-empirical Design Criteria Flow Chart
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Design Criteria A:Stability of excavation during operation
• Stability of jointed rock
• Avoidance of degradation of rock mass in contact with water
Design Criteria B:Minimum Principle Stress Criteria• Internal pressure exceeds
rock mass coverage
© Weh
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Design Criteria C:Limiting water losses and reach of the seepage flow
• Economic losses in terms of energy caused by water losses
• Dilution of the hydrological regime
• Slope instability on the valley flanks owing to uplift conditions
Design Criteria D:Rock mass permeability / conductivity• Minimize water movements in the
vicinity of the tunnel
© Bauert
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Design Criteria E:Deformation characteristics of rock mass
+ε
-p
+p
stress – strain relationship lining
stre
ss –
stra
in
rela
tions
hip
rock
mas
s
(con
solid
ated
)
stress – strain
relationship rock mass
pF(ra)pF(ra)
Increase of stiff
ness
due to consolid
ation gro
uting
strain-ε
stre
ss
strain
compression tension
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Decision matrix for lining systems
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Historical development of passive pre-stressed concrete linings
KW
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rbo
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ken
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rg 1
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tai 1
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9
NT
FP
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Lin
tha
l 20
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UW
ST
B 2
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tha
l 20
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OW
DS
T 2
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ren
we
rk 2
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0,0 2,0 4,0 6,0 8,0 10,0 12,0 14,0
TE
NS
ILE
RIN
G F
OR
CE
"Z
" [M
N/m
]
SLENDERNESS RATIO "SR" [m/m]
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NTFP: Project Information
© Weinhard © Wannenmacher
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NTFP: Design Criteria Assessment
Design Criteria NTFP
A : Long Term Stability B : Minimum Principle Stress C : Acceptable Water Losses D : Rock Mass Permeability E : Deformation Characteristics
© Wannenmacher © Perras
HYDRO 2013 – Tunnels and Underground Works
NTFP: Lining and Pre-stressing Concept
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Bärenwerk Pressure Tunnel
Salzburg AG. Salzburg AG.
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Design Criteria Bärenwerk
A : Long Term Stability B : Minimum Principle Stress C : Acceptable Water Losses D : Rock Mass Permeability E : Deformation Characteristics
Bärenwerk Pressure Tunnel
© Weh © Weh
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Bärenwerk Pressure Tunnel
Shotcrete
Grout Line
Waterproofing
Final Lining
Detail 1
Detail : Excavation
Grout line
Invert segment
Mortar bed
Waterproofing membraneglued on invert segment
Shotcrete
Detail : Pre- Stressing
Grout line
Invert segment
Mortar bed
Waterproofing membraneglued on invert segment
Waterproofing membrane vault
Final lining
Intersectionwaterproofing membraneand grout line
Shotcrete
Waterproofing membranewith overlapR = 1.39m
R=1.80m
Shotcrete
Grout Line
Waterproofing
Final Lining
Detail 1
Detail : Excavation
Grout line
Invert segment
Mortar bed
Waterproofing membraneglued on invert segment
Shotcrete
Detail : Pre- Stressing
Grout line
Invert segment
Mortar bed
Waterproofing membraneglued on invert segment
Waterproofing membrane vault
Final lining
Intersectionwaterproofing membraneand grout line
Shotcrete
Waterproofing membranewith overlapR = 1.39m
R=1.80m
Shotcrete
Grout Line
Waterproofing
Final Lining
Detail 1
Detail : Excavation
Grout line
Invert segment
Mortar bed
Waterproofing membraneglued on invert segment
Shotcrete
Detail : Pre- Stressing
Grout line
Invert segment
Mortar bed
Waterproofing membraneglued on invert segment
Waterproofing membrane vault
Final lining
Intersectionwaterproofing membraneand grout line
Shotcrete
Waterproofing membranewith overlapR = 1.39m
R=1.80m
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ContraContraProPro
Intense work preparation Qualified and
Experienced Grouting Operation
Monitoring and Engineeering on site required
Intense work preparation Qualified and
Experienced Grouting Operation
Monitoring and Engineeering on site required
Prooven long-term stability of pre-stressed pressure tunnels
Cost –effective method
Prooven long-term stability of pre-stressed pressure tunnels
Cost –effective method
Summary