Part 30/1 TrV-2 Erfarenhet från tunneldrivning under fritt vatten ‏ XI-2015 (Part 30, PP 2007, animation+p/r : 2015.11.20 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

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

Vaðlaheiðigöng Road Tunnel press ready press press press

Vaðlaheiðigöng Road Tunnel – rock collapse press ready press press

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 1993-1995 ready

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

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

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

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

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

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

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

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

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

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

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

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

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

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

PU resins love water for reaction polyurethanes water ready 20

convenient in low temperatures press press ready convenient in low temperatures press

3. Rock and groundwater temperature ready

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

Vaðlaheiðigöng Road Tunnel press press ready press

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

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

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

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

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

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 2010 -2011 press

? 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

press press ready

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

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

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

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

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

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

? ? ? press press ready press

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

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

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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, 133 36 Saltsjöbaden - Sweden Org. no: 556957 – 5433 Tel: 0046 (0)8 717 5714 Fax: 0046 (0)8 717 6042 Mobil: 0046 (0)704 217 012 E-mail: tomasz.najder@hotmail.com www.najder.se ready