1. Part 30/1 TrV-2 Erfarenhet från tunneldrivning under fritt vatten ‏
XI-2015
(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.
ready

2. One of the largest problems for sub-water
Safety:
One of the largest problems for sub-water
tunnelling is uncontrolled water ingress.
Two of the biggest risks are:
1. Immediate flooding.
2. Ground collapse associated with
water ingress.
press
ready
press

3. Vaðlaheiðigöng Road Tunnel
press
ready
press
press
press

4. Vaðlaheiðigöng Road Tunnel – rock collapse
press
ready
press
press

5. Breiđalsheiđi and Botnsheiđi road tunnels in Ísafjörður: grouting for rock sealing and stability. Conditions: very high water ingress under high water pressure of 70 bars into D&B tunnel. Very high water velocity in rock
ready

6. The tunnels of Breiđalsheiđi and Botnsheiđi
City of Ísafjörður
The tunnels of Breiđalsheiđi and Botnsheiđi
ready

7. Leakage 2 700 l/s !!! fault 2 No probe holes !!! fault 1 press press
ready

8. Botnsheiđi leg under construction – face close to fault 2
???
ready
Botnsheiđi leg under construction – face close to fault 2

9. X Rock grouting in Breiđalsheiđi and Botnsheiđi (Iceland) 1993-1994
Water pressure ~ approx. 60 bars
Water inflow ~ 50 l/s/hole
Water temperature ca. +20 ºC
fault
3 m/s
water X
ready
cement grouting

10. CaCl2
Ca(OH)2 Si
Cemsil
Cement mixes for rock grouting in Breiđalsheiđi and Botnsheiđi (Ísafjörður – Iceland)
ready 10 10

11. Mechanical packer for sequential grouting with cement grout and/or
PUR (A+B)
Mechanical packer for sequential grouting with cement grout
and/or
2-component polyurethanes according to TNa proposal
press
ready

12. 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)
press
press
press
ready

13. 1. Groutability (conductivity) of the cracked rock mass
2. Groundwater velocity and volume of water ingress in the leaking cracks
3. Rock and groundwater temperature
ready

14. 1. Groutability (conductivity) of the cracked rock mass
ready

15. OPC
MC, UFC
press
press
press
ready 15
press
press 15

16. 2. Groundwater velocity and volume of water ingress in the leaking cracks
ready

17. “hockey stick” reaction
Polyurethanes (fast-moderate-, slow reacting)
Sodium/natrium silicates
Epoxy resins
Cement based suspensions
“hockey stick” reaction
press
press
ready
press 17

18. Water velocity [mm/min]λ
WilkitFoam, GeoFoam λ = 15÷30 x
CarboPur λ = 3÷5 x
Wash-out effect
Water velocity [mm/min]
15 mm/s
De Neef Scandinavia AB 1991
Factor λ
= relation between volume of material grouted / material still remaining in the rock mass after hardening vs. ground water velocity in mm/min
press
press
ready 18

19. cement particles water Water is enemy to cement based grouts
(dilution, wash-out)
water
ready
cement particles 19

20. PU resins love water for reaction
polyurethanes
water
ready 20

21. convenient in low temperatures
press
press
ready
convenient in low temperatures
press

22. 3. Rock and groundwater temperature
ready

23. Low temperature problems with cement based grouts
Climate
Low temperature problems with cement based grouts
ready

24. Vaðlaheiðigöng Road Tunnel
press
press
ready
press

25. Catalysator (accelerator, aktivator) = CAT After Contact with Water
Chemical differences between so-called 2-component polyurethanes (“dual component” PUR) and 1-component polyurethanes (“single component” PUR)
Description
2-comp. PUR
1-comp. PUR
Base System
Resin = B
Reagents
Hardener = A
Catalysator (accelerator, aktivator) = CAT
Preparation
A + B
B + CAT
Reaction Starts
After Mixing
After Contact with Water
(min 6%)
Reaction Start Time
Almost Immediately
= f (temp.) → (20”÷ 30’)
Variable on Site
(“in situ”)
= f (temp., % CAT) → (1’÷ 6’)
Reaction Start
Set
Factory Pre-Set – otherwise option with “accelerators”
press
press
press
press
Hydrophilic grout will absorb the water it finds in the concrete or soil (rock).
Hydrophobic grout will repel it and push it away.
ready

26. 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
press
ready
press
press
press
press
Simple hand pump for water flushing through the packers and membrane pump for 1-comp. PU resins
press

27. Injection with 1-comp. PUR in rock
mechanical packer
ready
Injection with 1-comp. PUR in rock
1 mm
press
press
Injection with 1-comp. PUR in concrete

28. Combi – waterstops with 3 ”defense lines”:2 2 1 1 3 3
Combi – waterstops with 3 ”defense lines”:
Tortuous paths.
Expanding rubber (neoprene).
Injection hoses for 1-component PU resins.
press
press
ready
press

29. Combi – waterstops with 3 ”defense lines” – application in tunnels
Waterstop and separate injection hose – application in tunnels
press
ready

30. PUR leakage followed by ”reacted” silica sol (1 year after grouting)
Taccs, Resfoam ???
Sudden appearance of drill water leaking from the old (still open) grout hole followed by none reacted 1-comp. PU resin (1 year after grouting)
Sudden appearance of drill water leaking from the old (still open) grout hole
PUR leakage followed by ”reacted” silica sol (1 year after grouting)
press
ready
Torsgatan Access Tunnel
press

31. ?
40 kPa = 0.04 MPa = 0.40 kg/cm2
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.
Butron 2005
press
ready

32. press
press
ready

33. Cut & cover underground tunnel in Warszawa.
None succsessful conrete repairs with surface treatment
with SIKA 2 (on the right) and grouting with acrylates (to the left)
press
ready
press
press

34. Rock grouting using 1-component polyurethane resin (PUR)
(none reacted)
Resin
(none reacted)
Groundwater
Re-drilling
Rock grouting using 1-component polyurethane resin (PUR)
Stage 1: placing of packer
Stage 3: re-grouting
Stage 2: grouting
press
press
ready
press

35. ”Soda water phenomenon” with 1-component PUR
18 bar
press
ready

36. 1-component PUR My proposal: 2-component PUR mineral component (OMC)
Hydrophilic PUR
– limited range of penetration due to:
Too fast reaction.
Too low pumping rate.
components A+B
Component B
- polyisocyonate
2-component PUR
Component A
- polyol
components A+B
components A+B
My proposal:
2-component PUR or
mineral component (OMC)
(sequential grouting)
press
press
ready
The tunnels of Breiđalsheiđi and Botnsheiđi
press

37. Hybrid Injection Techniques
Sequential
Grouting
Liquid Mineral
Pure Resin (+Acc.)
injection
Crack system
press
press
Single Sequential Grouting
CarboTech (now Orica/Minova)
2-component polyurethane or
cement slurry grouting system
ready

38. Single Sequential Grouting Single Sequence Grouting
Cement grout
> 40 bars anti-return valve
To the packer
Rotating connector
Single Sequential Grouting
2-component polyurethane or
cement slurry grouting system
PU resin
Single Sequence Grouting
2-component polyurethane
and
cement slurry grouting system
press
ready

39. ? ? ?
press
press
ready
press

40. Underpinning by Single Sequence Grouting (de Neef)
press
ready
Underpinning by Single Sequence Grouting (de Neef)
1-component polyurethane and cement slurry

41. Underpinning by Single Sequence Grouting (de Neef)
press
ready
Underpinning by Single Sequence Grouting (de Neef)
1-component polyurethane and cement slurry – cont.

42. ready

43. 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)
ready