This document presents results from a study on the mechanical and flow properties of cement grouts at different temperatures. Three cement types (A, B, C) were used to prepare grout mixes with water-cement ratios ranging from 0.6 to 1.2. Tests measured the filtration, viscosity, setting time, bleeding, compressive strength and permeability of the grouts cured at 8°C and 20°C. The main findings were that curing temperature affects strength, with 8°C resulting in lower strength than 20°C; filtration stability is independent of temperature but depends on water-cement ratio; and true tunnel conditions involve both temperature and pressure, though pressure effects were not examined.

1. True Improvement in Grouting High pressure Technology for tunnellingTrue Improvement in Grouting High pressure Technology for tunnelling
Mechanical and flow properties of
cement grouts
True Improvement in Grouting High pressure Technology for tunnelling
Bahman Bohloli, Lameck Omondi Omolo, Magnus Soldal, Heidi Wilkinson and Elin Katrine Morgan
Norwegian Geotechnical Institute (NGI), Oslo
Nordic Grouting symposium, 26-27 September, Oslo

2. True Improvement in Grouting High pressure Technology for tunnellingTrue Improvement in Grouting High pressure Technology for tunnelling
Contents
• Introduction
• Experimental plan
• Flow properties of cement grouts
• Mechanical & hydraulic properties of cured
cement plugs
• Conclusions

3. True Improvement in Grouting High pressure Technology for tunnellingTrue Improvement in Grouting High pressure Technology for tunnelling
Introduction
• The objective: to understand behaviour of cement
grouts under true tunnelling conditions
• Actual temperature in tunnels is about 7-10 °C in
Norway
• Actual pressure in tunnels depends on the overburden
• Most available data on cements and cement grouts is
from the standard room temperature and
atmospheric pressure

4. True Improvement in Grouting High pressure Technology for tunnellingTrue Improvement in Grouting High pressure Technology for tunnelling
Introduction (Cont’d)
• Behaviour of grout is controlled by w/c ratio, grain size
distribution, …
• This study presents results of lab tests on three types of
cements at two different temperatures; 8 °C and 20 °C
• It does not consider any pressure during curing of
samples
• This study is part of the research project:
True Improvement in Grouting High pressure Technology
for tunnelling (TIGHT)

5. True Improvement in Grouting High pressure Technology for tunnellingTrue Improvement in Grouting High pressure Technology for tunnelling
Cement A
Cement B
Cement C
Cements used in this study

6. True Improvement in Grouting High pressure Technology for tunnellingTrue Improvement in Grouting High pressure Technology for tunnelling
Mix Grout Cured grout samples
W/C
ratio
Filtration
(Filter Press)
Viscosity
(Marsh Cone,
EN 445, Ring)
Setting time (Vicat-
neal, Calorimeter)
Bleeding
(cylinder)
Uniaxial compressive
strength (UCS)
Permeability
A1.2 1 3 2 1 2×2 1
A1.0 1 3 2 1 2×2
A0.8 1 3 2 1 2×2
A0.6 1 3 2 1 2×2
B1.2 1 3 2 1 2×2 1
B1.0 1 3 2 1 2×2 1
B0.8 1 3 2 1 2×2
B0.6 1 3 2 1 2×2
C1.2 1 3 2 1 2×2
C1.0 1 3 2 1 2×2 1
C0.8 1 3 2 1 2×2
C0.6 1 3 2 1 2×2
Characterization of cement grout and hardened grout samples

7. True Improvement in Grouting High pressure Technology for tunnellingTrue Improvement in Grouting High pressure Technology for tunnelling
Flow properties of cement grouts

8. True Improvement in Grouting High pressure Technology for tunnellingTrue Improvement in Grouting High pressure Technology for tunnelling
Filtration test: API Filter Press
- Provides data related to penetrability of grout
- Pressure on the grout= 100 psi (7 bar)
- Measure filtration until air reaches the outlet
- Filter sizes used= 63 and 75 mic.

9. True Improvement in Grouting High pressure Technology for tunnellingTrue Improvement in Grouting High pressure Technology for tunnelling
Results of filtration test

10. True Improvement in Grouting High pressure Technology for tunnellingTrue Improvement in Grouting High pressure Technology for tunnelling
Comparison of filtration ability of different
cements at 8ºC versus 20ºC
0
10
20
30
40
50
60
70
80
90
100
0,4 0,6 0,8 1 1,2 1,4
Passed(%)
W/C ratio
Percentage of grout passed through a filter of 75 µm,
for cements A, B and C at 8 vs 20 deg C.
A-20deg
A-8deg
B-20deg
B-8deg
C-20deg
C-8deg
Cement A
Cement B
Cement C
Filtration at 8ºC is not very
different from 20ºC, slightly
higher for cement C.
Cement A shows best
penetration
Cement B has lowest
penetration
Filtration increases with
increasing w/c ratio, (non-
linearly from 0.6 to 0.8, but
almost linearly thereafter)

11. True Improvement in Grouting High pressure Technology for tunnellingTrue Improvement in Grouting High pressure Technology for tunnelling
Comparison of filtration ability of different
cements through 63 & 75 micrometer filter at
20ºC
Very small difference
between filtration
through 63 vs 75 micron
filter
Cement A highest and
Cement B lowest
penetration
Filtration increases with
increasing w/c ratio.

12. True Improvement in Grouting High pressure Technology for tunnellingTrue Improvement in Grouting High pressure Technology for tunnelling
Mechanical & hydraulic properties of cured
cement plugs

13. True Improvement in Grouting High pressure Technology for tunnellingTrue Improvement in Grouting High pressure Technology for tunnelling
Sample
preparation

14. True Improvement in Grouting High pressure Technology for tunnellingTrue Improvement in Grouting High pressure Technology for tunnelling
Test Results:
Uniaxial
compressive
strength of
- cement A
- cured 8ºC/20ºC
- 4 days old
20°C
8°C

15. True Improvement in Grouting High pressure Technology for tunnellingTrue Improvement in Grouting High pressure Technology for tunnelling
Test Results:
Uniaxial
compressive
strength of
- all cements
- cured 8ºC/20ºC
- 4/7 days old
8ºC
20ºC

16. True Improvement in Grouting High pressure Technology for tunnellingTrue Improvement in Grouting High pressure Technology for tunnelling
Permeability of cured cement samples

17. True Improvement in Grouting High pressure Technology for tunnellingTrue Improvement in Grouting High pressure Technology for tunnelling
Conclusions
• Strength of grout samples cured at 8ºC is lower than
those cured at 20ºC
• Filtration stability of cements seems to be independent
of grout temperature, but is controlled by w/c ratio
• True tunneling condition implies presence of in-situ
pressure and temperature. This study included
temperature only but has not examined impact of
pressure on grout behaviour.