1. (Part 30, PP 2007, animation+p/r : 2015.06.02 short version compr.)
Part 30/1 TrV Beprövade tekniska lösningar för ”vattendrabbade” tunnlar i komplicerade hydrogeologiska bergförhållande
VI-2015 revised 2016
(Part 30, PP 2007, animation+p/r : short version compr.)
Copyright notice Unauthorised copying of this presentation as whole or in parts in any form or by any means, electronic, photocopying, recording or otherwise, without prior written permision is prohibited.
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2. för risk av bergras och katastrofal vatteninflöde.
1. TBM vs D&B koncept för undervattenstunnlar och tunnlar med hög vattentryck utsatta
för risk av bergras och katastrofal vatteninflöde.
2. Dränering vs isolering vs injektering för tunnels täthet.
3. Betonglining vs sprutbetong. Reparationer för tätning.
4. Missförstånd kring rätt val av injekteringsmedel och lillämpad metodik vs hydrologiska förhållande i tunnlar. Felaktig vs rätt användning av polyuretan harts för stabilisering och tätning av berg.
5. Spiling och bultning i tunnlar för bergstabilisering och tätning.
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3. Welcome to www.najder.se
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4. Grout = liquid → solid form in the crack
Grout An injection fluid, generally referred to as grout is a pumpable material (suspension, solution, emulsion or mortar) injected into a soil or rock formation which stiffens and sets with time and thereby changes the physical characteristics of the formation (for consolidation or/and for sealing)
1. Suspensions = particles suspended in water
Water + cement corns (alt. microcements, ultra fine cements, fly ash etc.)
Water + cement corns + fillers (ballast like sand)
liquid → solid form by hydratation
2. Solutions = chemicals diluted in water
Water + sodium/natrium silicates + reactans
Water + colloidal silica SiO2 + NaCl or CaCl2
liquid → solid form by gelling (chemical reaction)
3. Resinous grouts = pre polymers or monomers or isomers
(2 or more components in liquid and/or powder form)
Water + acrylic polimers (hydrogels)
1-comp. and 2-comp. polyurethanes
Urea-silicate resins (foams)
Phenolic foams
liquid → solid form by polymerisation (3-D linking)
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6. Rock fracturing by water. False Lugeon values !!!
Hydrojacking, i.e. the dilation (or widening) of existing paths begins in rock types of little strength at pressures smaller than 10 bar (in hard rock, in sedimental even lower).
It causes an over-proportionate increase of the water take before the reference pressure is reached.
Under such conditions the Lugeon-value referring to 10 bar pretends a larger permeability compared to the original one. This discrepancy impairs our assessment.
In rock types of great strength the dilation of existing paths begins at pressures above bar, thus the absorption rate at the reference pressure reflects still the original permeability.
Hydrofracturing splits latent discontinuities producing a fissure as soon as the testing or grouting pressure reaches “the critical pressure”, different from case to case.
It causes a much larger effect of pretence: the latent planes absorb no water during the low-pressure steps but large amounts after fracturing.
It is obvious that the wrong assessment of the original permeability has considerable consequences
Hydrojacking and hydrofracturing are particularly effective in grouting work where even higher pressures are usually applied. (?????)
Friedrich-Karl Ewert
Rock fracturing by water. False Lugeon values !!!
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7. There are two ways to set, or harden, liquid sodium silicates for grouting applications.
The first way is by lowering the silicate’s pH. This causes the SiO2 species to polymerize into a gel. Some setting agents will hydrolyze over time and form an a
cid that will set the silicate. By controlling the composition of the setting agent, and therefore the rate of hydrolysis, the gel time of the grout can be tightly controlled. The second way to set a silicate grout is to react it with soluble metals to form insoluble metal silicates.
These grouts generally have higher strength and are lower in cost. Typically, PQ’s N® sodium silicate is used for grouting applications. It is diluted to reduce its viscosity, so that it penetrates soils more easily.
The viscosity adjustment takes into account the soil permeability and the strength requirement of the grouted mass.
The strength of a silicate-grouted soil is influenced by several factors: concentration of silicate in the grout formulation composition and particle size distribution
of the soil selection and amount of hardening agents  chemistry of the surrounding waters Soil grouting and ground modification with sodium silicate is a sophisticated engineering application and requires specialized equipment and expertise. ? ? or =
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8. ViscosityOPC ˃˃ Viscositywater α
Typical rheological laws for two types of fluids
pressure (bar)
shear stress
OPC Binghamian fluid
CohesionOPC ˃˃ Cohesionwater (= 0)
ViscosityOPC ˃˃ Viscositywater α
viscosity
Water = Newtonian fluid
yield stress (cohesion)
Bindham yield point
grout flow (l/min)
shear strain or shear rate
Cement suspension ≠ water !!!!!
Lugeon test is performed with Newtonian fluid
Grouting is performed with Binghamian fluid
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9. ≤ 1.0 ˃ 1.0 = fracturing !!! Amenability Lugr Ac = Luwa
Amenability is the ability of the particular grout to penetrate joints and other defects premeated with water.
It is defined by the amenability coefficient (Ac) of the grout, which is expresssed as follows:
Lugr
Ac =
Luwa
≤ 1.0
˃ 1.0 = fracturing !!!
where: Ac = amenability coefficient
Lugr = Lugeon permeability of the grout
Luwa = Lugeon permeability of water
The grout rheology is to be adjusted so as to maintain as high an amenability coefficient
as possible.
This should generally be greater than 75%, and preferably higher.
(Nauts 1995)
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10. The proposal of rock classification vs. groutability
Lugeon
Lugeon 1a 2a
clay fill
stable cement grouts
chemicals and resins 1b 2b
chemicals and resins
chemicals and resins
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Recommended:
High grout-take
Low grout-take
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chemicals
resins

11. OPC
MC, UFC
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12. “hockey stick” reaction
Polyurethanes (fast-moderate-, slow reacting)
Sodium/natrium silicates
Epoxy resins
Cement based suspensions
“hockey stick” reaction
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13. cement particles water Water is enemy to cement based grouts
(dilution)
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cement particles 13

14. PU resins love water for reaction
polyurethanes
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15. pumping pressure + CO2 (expansion pressure) One-component PU resins
Viscosity vs. time
2’ ÷ 12’
30” ÷ 3’ +
0.25 ÷ 10%
x 10 ÷ 30
pumping pressure
pumping pressure CO2 (expansion pressure)
One-component PU resins
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Simple hand pump for water flushing through the packers and membrane pump for 1-comp. PU resins
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16. Injection with 1-comp. PUR in rock
mechanical packer
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Injection with 1-comp. PUR in rock
1 mm
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Injection with 1-comp. PUR in concrete

17. Fast and moderate reacting two-component PU resins
Viscosity vs. time
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x 1 ÷ 8 (15)
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A:B = 1:1
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to the packer
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18. convenient in low temperatures
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convenient in low temperatures
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19. inflatable, disposable packers (drillable or none drillable)2
BVS
inflatable, disposable packers
(drillable or none drillable)
with integrated static mixer (no. 2) for proper mixing of comp. PU resins
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20. 1. TBM vs D&B koncept för undervattenstunnlar och tunnlar med hög
vattentryck utsatta för risk av bergras och katastrofal vatteninflöde
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21. press
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22. There are two ways to set, or harden, liquid sodium silicates for grouting applications.
The first way is by lowering the silicate’s pH. This causes the SiO2 species to polymerize into a gel. Some setting agents will hydrolyze over time and form an a
cid that will set the silicate. By controlling the composition of the setting agent, and therefore the rate of hydrolysis, the gel time of the grout can be tightly controlled. The second way to set a silicate grout is to react it with soluble metals to form insoluble metal silicates.
These grouts generally have higher strength and are lower in cost. Typically, PQ’s N® sodium silicate is used for grouting applications. It is diluted to reduce its viscosity, so that it penetrates soils more easily.
The viscosity adjustment takes into account the soil permeability and the strength requirement of the grouted mass.
The strength of a silicate-grouted soil is influenced by several factors: concentration of silicate in the grout formulation composition and particle size distribution
of the soil selection and amount of hardening agents  chemistry of the surrounding waters Soil grouting and ground modification with sodium silicate is a sophisticated engineering application and requires specialized equipment and expertise.
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23. Proposal for tunnel under the English Channel from 1908
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24. Kárahnjúkar Hydropower Project 2004÷2008
Diversion Tunnels at dam 2.4 km (Kar 14)
Headrace Tunnel 53.0 km (Kar 14)
Grouting galleries at dam  0.5 km    (Kar 14)
Cable tunnel  km
Hraun Diversion 2.0 km
Grjótá Diversion km
Adit km (Kar 14)
Adit km (Kar 14)
Adit km (Kar 14)
Surge Tunnel km (Kar 14)
Drainage Tunnel 0.7 km (Kar 14)
Penstocks km (2x)
Access to Powerhouse 1.0 km
Tailrace Tunnel km
Total Tunnel Length: 73.0 km (D&B=10 km, TBM=63 km)
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Kárahnjúkar Hydropower Project 2004÷2008 24 24

25. TBM
D&B
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26. Solid hard rock with low chance for serious water or soil inflow
TBM type Open Gripper
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27. Jökulsa Diversion Tunnel – rock falling down in front
of cutter head and overbreak
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28. Rock falling down from the fault and overbreak
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29. 29 Gravel and clay filled fault at the cutterhead
Stage 2: huge water ingress from the fault;
TBM cutterhead passed the fault
Stage 3: wash-out of the fill from the fault (TBM)
Stage 4: material washed-out from the fault
Stage 1: TBM in progress in water scenery
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30. Series of wide faults – huge volume of water ingress and collapsing rock
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31. - faults = 1% of tunnel length
No production
Kárahnjúkar HRT:
- faults = 1% of tunnel length
responsible for
80% of coming water !!!!
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32. TBM type Earth-Pressure-Balance (EPB)
None stable soils, soft types of rock, cracked or carstic rock with high chance for serious water or soil inflow
TBM type Earth-Pressure-Balance (EPB)
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33. TBM type Slurry Schield
Unstable faces with none stable gravelly soils, mix conditions, soft types of rock – with high chance for serious water or soil inflow and/or air escape
TBM type Slurry Schield
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34. TBM Type Dual mode Mixed Schield (Herrenknecht - Hallandsås)
1825
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35. Thank You for Your attention!
THE END of Part 1
Thank You for Your attention!
Ph.D Civ. Eng. Tomasz Najder
Senior Consultant
Najder Engineering AB
Movägen 3,
Saltsjöbaden - Sweden
Org. no: – 5433
Tel: 0046 (0)
Fax: 0046 (0)
Mobil: 0046 (0)
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