Why concrete gets wet. Make truly waterproof concrete, maintanance-free. The 11 mechanisms of corrosion of reinforced concrete, and how to stop them.

1. Delivering Design-Life, Membrane-Free
Concrete Waterproofing & Durability
in Underground Concrete Infrastructure

2. • Identify Advantages of Waterproof Concrete
• Review Water Transport Mechanisms in concrete
• Identify Primary Water Transport Mechanism and
Key Physical Properties of Waterproof Concrete
• Review the Effects of Hydrophobic Pore-blocking
Ingredients (“HPI”) on Key Properties
• Verifiy by
– independent laboratory testing
– long-term field performance
• Review Performance-Based Specification
HPI Concrete;
Truly Waterproof, Time-Proven
Alternative to Membranes

3.  The function of underground structures is to
separate the proposed activities from the
underground elements, especially water.
 ALL concrete gets wet because it sucks in water –
Therefore all hollow/air-filled concrete structures
below water will absorb and transmit water &
damp, along with contained salts and/or acids.
 This means that where dry and/or durable
performance is required, these concrete structures
must be proofed against water penetration in order
to fulfil their function successfully.

5. SO, WHEREVER THERE IS A HOLE OR
DAMAGED POINT IN THE MEMBRANE,
FOR WHATEVER REASON …

6. O2
Absorbed
Water
Evaporated Water “DEW” Point
Corroding Reinforcing Steel
Chloride Build-up as water evaporates

7. SO, HOW SERIOUS CAN FAILED
WATERPROOFING BECOME …?

8. 1. Chloride Attack on Embedded Metals
2. Sulphate Attack on Cement Paste
3. Acid Attack on Cement Paste and Embedded Metals
4. Delayed Ettringite Formation (DEF)
5. Alkali Attack on Reactive Aggregates (ASR)
6. Pure Water Attack on Cement Paste (snow melt, etc.)
7. Galvanic/Electrolytic Attack on Embedded Metals
8. Freeze / Thaw Attack on Cement Matrix
9. Surface Spalling due to Salt Crystallisation
10. Fire / Very High Temperature “Explosive Spalling”
11. Expansion/Contraction Cycling caused by Wetting/Drying
These are the mechanisms of corrosion / destruction, NOT the cause
© Copyright Cementaid International Ltd.

9. In all of the eleven mechanisms of corrosion /
destruction of reinforced concrete, there are;
 6 Chemical Reactions. (1,2,3,4,5,6)
 1 Electrolytic Reaction. (7)
 4 Physical Actions (8,9,10,11)
But there is ONLY ONE COMPONENT in these
11 mechanisms that is common to
 ALL CORROSION / DESTRUCTION OF
CONCRETE
© Copyright Cementaid International Ltd.

10. Water…
Water is;
•A solvent
•An electrolyte
•A chemical reactant
•A medium in which chemical and electrolytic reactions take place
•A physical agent of volume change
•A carrier of reactive and reacted materials
THE PRESENCE OF WATER IS
THE CAUSE OF ALL CORROSION OF REINFORCED CONCRETE
© Copyright Cementaid International Ltd.

11. © Copyright Cementaid International Ltd.

12. If you could produce concrete that is itself waterproof…
… Then waterproofing membranes, their labour, time and
costs – as well as corrosion & maintenance itself – would be
eliminated.
“THE PRESENCE OF WATER IS
THE CAUSE OF ALL CORROSION OF REINFORCED CONCRETE
& THE SOURCE OF ALL CONCRETE WATERPROOFING DELAYS & COSTS”
© Copyright Cementaid International Ltd.

13. 1. Chloride Attack on Embedded Metals
2. Sulphate Attack on Cement Paste
3. Acid Attack on Cement Paste and Embedded Metals
4. Delayed Ettringite Formation (DEF)
5. Alkali Attack on Reactive Aggregates (ASR)
6. Pure Water Attack on Cement Paste (snow melt, etc.)
7. Galvanic/Electrolytic Attack on Embedded Metals
8. Freeze / Thaw Attack on Cement Matrix
9. Surface Spalling due to Salt Crystallisation
10. Fire / Very High Temperature “Explosive Spalling”
11. Expansion/Contraction Cycling caused by Wetting/Drying
© Copyright Cementaid International Ltd.

14.  It would not absorb water or
transmit dampness
- (That’s why membranes were used!)
- It would stay DRY inside –
- It would be corrosion-proof
- Truly waterproof concrete that does not need a
membrane, would also be corrosion-proof
SO HOW DOES WATER GET INTO CONCRETE?
- WHAT ARE THE TRANSPORT MECHANISMS?

15.  Capillaries & air voids make up ~
6 - 10% of the volume of good
quality concrete
 Only two possible water transport
“mechanisms”
1) Hydrostatic pressure
 Test : “Permeability”
Measures rate of moisture movement under
pressure – “saturated flow”
e.g. Submerged concrete
2) Capillary absorption ..it SUCKS !
 Test : “Absorption”
Measures rate of moisture movement by
capillary action – “Suction”
e.g. Air-exposed concrete / hollow-submerged
 To be truly waterproof, an integral waterproofing
ingredient must address both of these
mechanisms
 Which is the PRIMARY WATER
TRANSPORT mechanism?

16.  "Clearly ‘permeability’ is not a good measure of
resistance to chloride penetration.”
 “Capillary Absorption is the primary
mechanism by which water & chlorides
infiltrate concrete.”
 “The speed of capillary absorption is of the
order of 10¯6 m/s - a million times faster than
permeability.”
 “Up to 20 mm of quality concrete can be
penetrated in a few hours by this mechanism on
first contact with water containing chlorides.”

17.  Control of water transmission by capillary
action / absorption is essential for truly
waterproof concrete.
 Densifying / permeability-reducing additives
(e.g.SCM’s) DO NOT significantly reduce
Absorption -
State of the Art, best possible Plain Concrete;
 Low Permeability + Low Diffusion
= Self-saturating, wet concrete
= will corrode, needs membrnaes
Truly Waterproof Concrete; Key Properties ;
 Low Permeability + Non-Absorptive
= waterproof , DRY concrete
= proof against corrosion, membrane-free
 “Hydrophobic, Pore-blocking
Ingredients” (HPI) were developed by
Cementaid to deliver these Key
Properties. HPI concrete has been in
use in structures world-wide for more
than 50 years (since 1962).Water applied to this 50MPa tunnel-
concrete is immediately absorbed

18.  Liquid ingredient, dosed at
batching plant, replacing an equal
amount of batch water.
 1) Reverse Capillary-Absorption
2) Physical Pore-blocking ability
 Superplasticiser typically used to limit
water:cement ratio (max. 0.45) and
optimise workability
- Min. cement 335kg/m3 / 32 Mpa (564lbs./yd3 /4,600psi)

19.  Hydrophobic Matrix profoundly modifies Contact Angle of water
 Hydrophobic capillary system reverses “wicking” or absorptive action
 Hydrophobic Matrix™ is inherently non-absorptive & “un-wettable”
throughout section thickness, including around reinforcement
 “Caltite” HPI additionally deposits polymer pore-blocking particles
which physically block pores and capillaries subject to hydrostatic
pressure

21.  Water, salt, acid or other
aqueous solutions are
NOT ABSORBED
 Water contact is confined
to extreme outer surface
 Steel remains encased in
permanently DRY
CONCRETE
 Laboratory verified
 50 Years in field strucutres

22.  Laboratory research by
VicRoads (AUS) confirms
maximum void reduction
(ASTM C642) using HPI
(Caltite), & concludes…
 “This is a very efficient
material. (Caltite) has been
found to outperform both
conventional as well as
SCM concretes (silica fume,
slag & PFA) with far greater
reductions in VPV. “
 Caltite reduced permeable
voids by 1.5, 2, 3 and 6 times,
over silica fume, PFA, slag &
crystal-growth additive
respectively
0
5
10
15
20
25
30
CALTITE
Silica
Fume
PFA
ggbf
Slag
crystal-
growth
% REDUCTION IN
VOLUME OF PERMEABLE
VOIDS (VPV)
Australian State Government Research
VicRoads – Geopave, Victoria (1998) - VPV

23.  NSW RTA research
confirms maximum
REDUCTION in Water
Uptake (capillary action) is
provided by HPI
concrete (“Caltite” & “3CC”)
 “Densifying” (2)
(permeability reducing)
additives have only a
marginal effect on water
transport by capillary
action
%Reduction in Water Uptake
HPI 1 (“CALTITE”)92.3%
HPI 2 (“3CC”) 91.5%
Crystal-growth 12.5%
0
20
40
60
80
100
Everdure
Caltite
3CC
Crystal-
growth
% REDUCTION in
WATER UPTAKE
50 MPa concrete

24.  NSW RTA research
demonstrates completely
effective protection against
water & chlorides is provided
by HPI concretes
(Caltite & 3CC)
Conclusion: “The HPI’s can
be used to protect
concrete against
moisture & chloride
ingress under conditions
of atmospheric
exposure.”
0
20
40
60
80
100
%Chloride
Reduction
at 20mm
Everdure
Caltite
3CC
Crystal-
growth
% REDUCTION in
CHLORIDE PENETRATION
50 MPa concrete
% REDUCTION in Chlorides
@ 20 mm depth
HPI 1 (“CALTITE”) 100.0 %
HPI 2 (“3CC”) 98.7 %
Crystal-growth 23.5 %

25.  NSW RTA
research
demonstrates
completely effective
protection against
water & chlorides is
provided by HPI
concretes
(Caltite & 3CC)
76.42
62.05
3.15
99.7797.86
30.98
98.41 100
25.35
0
10
20
30
40
50
60
70
80
90
100
%
0 - 5mm 10-15mm 20-25mm
% REDUCTION in Chloride (CTI / RTA)
CALTITE 3CC CRYSTALGROWTH

26. Conclusions;
 “..The HPI
concretes (Caltite &
3CC)..lose more weight
during each drying
phase than was
absorbed in the
previous immersion
phase, with a
continual weight
reduction leading to
drier concrete.”
CONTROL
HPI (“caltite”)

27. Conclusions..
“”..The (silicate-type)
additive showed little
difference to untreated
concrete, absorbing
and losing water freely
during each stage of
the test.”
CONTROL
crystal growth

29. “Saline Water will be freely available but will have very high salinity.
Generally saline water is used for the plant processes, wash-down of
equipment, road watering, dust suppression, etc.”
Water Analysis – High-temperature, hypersaline bore-water
pH 5.3 – 7.25
TDS 15,8000 – 217,000mg/l
CO3-- <0.3mg/l
SO4-- 8,500 – 12,000mg/l
Cl- 8,8000 – 12,2000mg/l
Na+ 511000 – 70000mg/l
Ca++ 640 – 1050mg/l
Mg++ 6,500 – 9,000mg/l
K+ 90 – 435mg/l

30. Surface Appearance …
Standard @ 15 Yrs HPI (CALTITE) @ 17 Yrs

31. 17-year Chloride profile …

32. Sulfate profile …

33. Ground Water
Analysis;
Chlorides:
53,000 mg per litre
Sulphates:
7,200 mg per litre
*Service temperatures up to 50°C (summer)
 Truly waterproof concrete
will remain durable even
under severe exposure
conditions ..

34. HPI concrete (CALTITE)
after 18 Years
BHP Water Pipeline - Port Pirie Salt Pan, SA
S. Aust. Govt. Engineering & Water Supply Dept. (1960 / 2002)

35. CALTITE concrete (“Caltite”)
after 40 Years
BHP Water Pipeline - Port Pirie Salt Pan, SA
S. Aust. Govt. Engineering & Water Supply Dept. (1960 / 2002)

36. HPI (“Caltite”) concrete
after 50 Years
BHP Water Pipeline - Port Pirie Salt Pan, SA
S. Aust. Govt. Engineering & Water Supply Dept. (1960 / 2012)

37. HPI concrete used to
construct permanently dry
concrete retaining wall. A
part of the 6 level deep
basement structure, built
into the large hill behind
the development.
HPI concrete wall was
shotcreted straight onto
the excavated rock face
then finished to a fine
surface
Membrane-free waterproof
retaining wall plus
Corrosion-protection of the
rock anchors and.
NO membranes, NO
problems, NO protection,
NO delays, NO hassles,
NO damage by other
trades, NO maintenance.

38.  membrane-free HPI (Caltite System)
concrete basements extending
up to 19m below sea level.
 design & construction simplified
 significant cost savings
 construction schedule advanced
and time-savings considerably
exceeded cost of HPI concrete
additive
 Developer figured increased
asset value, with no
waterproofing maintenance or
corrosion repair costs - ever(Lend Lease)

39. • Seepage through
previous tunnel
linings creating
safety hazard,
especially in
winter months.
• Colorado
Department of
Transportation
specified HPI
(“CALTITE”) be
included in new
tunnel lining
shotcrete mix ….
Bear Creek Tunnel
Colorado Department of Transportation (C-DoT)

40.  HPI (CALTITE System) concrete
Shotcrete
 Durability Protection against both
Freeze/Thaw and De-icing salt
spray
 Prevention of water transmission
and formation of potentially lethal
“stalactites”.
• The finished reinforced HPI
(CALTITE) shotcrete layer
proven to be dry &
completely effective.

41.  Longest underground road tunnel in SE Asia.
 HPI (“Caltite”) concrete used to eliminate membranes
in contracts C421 & C424
 Simplified design, detailing & construction
 Simplicity & ease of repair to “holes”
 Hand-over of HPI Concrete sections on-time, within-
budget, DRY and leak-free.

42. Stage 1: Stage 2:
3CC System
concrete
blinding layer
100mm
depth
KingPost
100mm
Recess formed
by Main Con.
B2 slab
blinding layer
B2 slab
3CC System
concrete
Weldcrete slurry
Calgrout No. 7 +
3CC admixture
3CC SYSTEM
TYPICAL WATERPROOFING DETAILS
TO KING POST
Everdure Waterstop
to be installed prior to
casting of B2 slab

43.  HPI (“Caltite”) concrete used for
waterproofing & durability of ~20
kms sewage conveyance
tunnels, up to 100m below sea
level.
 Lower “W” twin-tunnel HPI
concrete section being cast &
cured, before casting upper “M”
twin-tunnel section over top

44.  New main underground
pumping station 55m diameter
+ 40m deep
 HPI (“Caltite”) concrete used
for waterproofing & durability of
diaphragm wall and cap 800 –
1000mm thick

45.  Base Slab Tunnel section between
Raffles Station and City Hall
 Ground pH values at 2.3
 HPI concrete tunnel base slab cast
using “Cut & Cover” (“Caltite System”)

46. ExistingDiaphragmWall
ExistingDiaphragmWall
CDWallwithNormalConcrete
CDWallwithNormalConcrete
Normal Concrete Normal Concrete
Normal Concrete
HPI (Everdure Caltite) Concrete at
top 300mm level
HPI(3CC)Concrete
3CCConcrete
Basement Internal
CHANGI LINE MRT C504 PROJECT
STATION WATERPROOFING DETAILS
TYPICAL SECTION
SKETCH NO. 1
For slab details, please
refer to sketch no. 3
Refer to
sketch
no. 2
Refer to
sketch
no. 4
Refer to
sketch
no. 5
Refer to
sketch no. 6

47.  Use of HPI (“Caltite”) concrete directly against diaphragm wall eliminates time
& creates additional internal space

48.  HPI concrete roof slab over station ticketing
concourse (“3CC System”)
 HPI concrete Suspended Canal (“3CC System”)
 HPI concrete (“Caltite System”) Base Slab at
lowest platform level ( - 30 metres, no membrane)

49. Singapore MRT projects; Membrane-free HPI concretes
(“Caltite” and “3CC”) cast in base slabs, walls and some roofs of
MRT stations, Cut and Cover tunnels and Cross passages.
Since end 1980s until now, more than 33 stations employed
HPI concrete to eliminate the risks & cost of membranes.
Singapore Mass Rapid Transit (MRT)
Membrane-free HPI Concrete Structures (“Caltite” & “3CC”)

50. University of Malaysia - UNIMAS
SERVICES TUNNEL AT KUCHING, MALAYSIA
Completion: 2004
HPI concrete: 20,000m3 (“3CC”)
Tunnel depth: 10m below ground
and adjacent to lake.

51. HPI Concrete; Acid-Resistance ... Photo @ 3 months
2 x HPI “pots (left) + 1 x Plain concrete “pot” (right) filled w 86% sulphuric acid;
Plain pot disintegrated lin ess than 48 hours,
leaving HPI pots in standing acid.
After 28 days, “Square” HPI pot emptied for
surface-inspection. & showing minor etching.
After 3 months “Round” pot still providing
effective containment
LEFT: Plain pot after 48 hours
RIGHT: HPI (“Caltite”) pot after
3 months

52.  Aggressive (acidic)
ground conditions
 Groundwater pH as
low as 2.5
 Membranes deleted
and HPI concrete
used in all concrete in
ground contact (Caltite
System)

53. CHEVRON Geothermal Power Plant; Gunung Salak, Indonesia
ABOVE: HPI concrete slurry sumps for hot discharge from
exploration drilling points, which contains Sulfuric Acid
(H2SO4).
- Smooth-trowelled sections unaffected after 3 years
- Un-trowelled sections show minor surface-etching only
Previous plain concrete sumps required repairs after only
2-3 years, resulting in high repair and downtime costs.
LEFT: New HPI concrete sumps built for project expansion
Higher density of smooth-trowelled
finish on HPI concrete shows no
signs of acid-erosion/wear
Surface-etching only of “rough”
finished HPI concrete

54. © Copyright Cementaid International Ltd.

55. 1. Have a W/C ratio not exceeding 0.45
2. Contain a time-proven effective Hydrophobic,
Pore-Blocking Ingredient (HPI) providing a corrected
30-minute water absorption value not greater than 1%
w/w, tested in accordance with BS1881; Part 122;
1983, except the age at test shall be 7 days.
3. The HPI used must have an independently verified
record of successful use in the field of not less than
25 years, with no seepage, reinforcement corrosion or
diminution of effect on Absorption.
© Copyright Cementaid International Ltd.
All Waterproof & Corrosion Resisting concrete shall;
 Have an optimum minimum Ordinary Portland Cement (OPC) content of
not less than 570 lbs./y3 (or as recommended for Blended Cements)

56. Well here is the twist….
 The HPI material(s) used
in the structures shown
here have been time-
proven effective & in
constant use globally
since 1962 i.e. 52 years
 But integrally
waterproofed concrete
has been in use in major
global infrastructure for
even longer ….

57. Waterproof concrete is really the established technology !!!
a
Opus Caementicium (pozzalanic) >> Opus Signium

58. Waterproof Concrete;
An Alternative
to Membranes
Hydrophobic Pore-blocking Ingredients (HPI)
(Everdure CALTITE & 3CC Systems)
w w w . c e m e n t a i d . c o m
Waterproof, Durable Concrete

59. Cracks are NO problem, …
Because HPI concrete is permanently,
inherently,
DRY!
Water/moisture in crack/void space ONLY – matrix remains dry
Allows easy location/ID of seeping void
Seepage easily rectified by grout injection, with superior bond & life
Dry HPI-matrix provides corrosion- immunity at cracks …
© Copyright Cementaid International Ltd.

60. Cracks in plain concrete create
dramatically larger surface areas
for water to be absorbed into the
matrix.
Worse. This oxygenated water is
very rapidly absorbed along the
porous steel /concrete interface,
resulting in classic ‘cigar’ shaped
spalling.
Interior surfaces of any crack in Caltite
concrete are Hydrophobic and Pore
Blocked. Water cannot be absorbed
through any HPI concrete surface.
MOST IMPORTANTLY. No water can
be absorbed along the embedded
steel bars, because they are
embedded in HPI concrete that
cannot get wet.
Case Study © Copyright Cementaid International Ltd.

61. Demonstration of
HPI Corrosion-Immunity At Cracks …
CRACKS DON’T MATTER
Background;
During a Caltite basement wall pour, the steel reinforcement frame shifted during
casting and was half exposed on stripping. Regrettably, the fault was covered up
with a 40mm sand/cement render, rather than demolish and rebuild the section.
The problem was discovered 8 years later, when the salt water leaking from the
upper level room of the salt water pump house to the surface render, had caused
the partially exposed reinforcing steel to corrode so badly that it blew off the
render, to show the corroding steel protruding from sound Caltite concrete.

62. © Copyright Cementaid International Ltd.

63. © Copyright Cementaid International Ltd.

64. © Copyright Cementaid International Ltd.

65. © Copyright Cementaid International Ltd.

66. © Copyright Cementaid International Ltd.

67. Waterproof Concrete;
An Alternative
to Membranes
Hydrophobic Pore-blocking Ingredients (HPI)
(Everdure CALTITE & 3CC Systems)
w w w . c e m e n t a i d . c o m
Waterproof, Durable Concrete