TecEco Technology and Geopolymers

1
TecEco Technology and Geopolymers
Can we create more polymeric non hydration
species using Ca-Mg cements?
It is time to deploy new technology materials
like geopolymers and TecEco cement binders that
offer waste utilisation, emissions reduction,
capture and sequestration.
Sustainability will be the biggest business on
the planet if we want to survive the future.
Auguste Rodin The Thinker
I will have to race over some slides but the
presentation is always downloadable from the
TecEco web site if you missed something.
John Harrison B.Sc.
B.Ec. FCPA.
2
TecEco Binder Systems and Geopolymer

• Geopolymers and TecEco binders have much in
  common.
• Both are sustainable materials with common
  deployment issues e.g.
• Response to the reality of carbon taxes.
• Lobby groups and competition product associations
  e.g.
• Portland cement industry putting out information
  to diffuse and confuse regarding geopolymer and
  TecEco technology.
• Lobby groups having a disproportionate say on
  government committees etc.
• Research development and deployment issues.
• Energy issues.
• Government policy issues.
• Development of standards and codes of practice?
• Can we learn from each other? Can we help each
  other?
• There are also features of tec-cement chemistry
  that invoke hydrolysis and more polymeric
  reactions.

There are definitely benefits to co-operation
between the two emerging technologies e.g. EU
research funding.
3
The Problem A Planet in Crisis
TecEco are in the BIGGEST Business on the Planet
- Solving Sustainability Problems Economically
A Planet in Crisis?
4
A Demographic Explosion
?
Undeveloped Countries
Developed Countries
Global population, consumption per capita and our
footprint on the planet is exploding.
5
Atmospheric Carbon Dioxide
6
Global Temperature Anomaly
7
The Techno-Process
Our linkages to the bio-geo-sphere are defined by
the techno process describing and controlling the
flow of matter and energy. It is these flows that
have detrimental linkages to earth systems.
Earth Systems Atmospheric composition, climate,
land cover, marine ecosystems, pollution, coastal
zones, freshwater systems, salinity and global
biological diversity have all been substantially
affected.
Detrimental affects on earth systems
Move 500-600 billion tonnesUse some 50 billion
tonnes
8
Ecological Footprint
Our footprint is exceeding the capacity of the
planet to support it. We are not longer
sustainable as a species and must change our ways
9
Impact of the Largest Material Flow - Cement and
Concrete

• Concrete made with cement is the most widely used
  material on earth accounting for some 30 of all
  materials flows on the planet and 70 of all
  materials flows in the built environment.
• Global Portland cement production is in the order
  of 2 billion tonnes per annum.
• Globally over 14 billion tonnes of concrete are
  poured per year.
• Over 2.1 tonnes per person per annum

TecEco Pty. Ltd. And the geopolymer industry both
have important technologies for improvement in
sustainability and properties
10
Embodied Energy of Building Materials
Concrete is relatively environmentally friendly
and has a relatively low embodied energy
Downloaded from www.dbce.csiro.au/ind-serv/brochur
es/embodied/embodied.htm (last accessed 07 March
2000)
11
Average Embodied Energy in Buildings
Most of the embodied energy in the built
environment is in concrete.
But because so much is used there is a huge
opportunity for sustainability by reducing the
embodied energy, reducing the carbon debt (net
emissions) and improving properties.
Downloaded from www.dbce.csiro.au/ind-serv/brochur
es/embodied/embodied.htm (last accessed 07 March
2000)
12
Emissions from Cement Production

• Chemical Release
• The process of calcination involves driving off
  chemically bound CO2 with heat.
• CaCO3 ?CaO ?CO2
• Process Energy
• Most energy is derived from fossil fuels.
• Fuel oil, coal and natural gas are directly or
  indirectly burned to produce the energy required
  releasing CO2.
• The production of cement for concretes accounts
  for around 10 of global anthropogenic CO2.
• Pearce, F., "The Concrete Jungle Overheats", New
  Scientist, 19 July, No 2097, 1997 (page 14).

CO2 CO2
The article by Fred Pearce was based on a 1994
article by Joseph Davidovits of the Geopolymer
Institute titled Global Warming Impacts on the
Cement and Aggregates Industries. World
Resources Review, pages 263-278, volume 6, number
2.
13
Cement Production Carbon Dioxide Emissions
Between geopolymers, tec, eco and enviro-cements
we can provide a viable much more sustainable
alternative.
14
Sustainability

• Sustainability is a direction not a destination.
• Our approach should be holistically balanced and
  involve
• Everybody, every process, every day.

Geopolymers TecEco Cements Low Emissions
ProductionMineral Sequestration Waste
utilization
Emissions reductionthrough efficiency
andconversion to non fossil fuels
Geological Seques-tration
Common Contributions?
15
Materials Affect Underlying Molecular Flows
Recycle
Waste only what is biodegradable or can be
re-assimilated
Take only renewables
? Manipulate ? Make ? Use ?
ReuseRe-make
e.g. heavy metals, cfcs, chalogen compounds and
CO2
?Materials? ?
Underlying molecular flows ?
Materials control How much and what we have to
take to manufacture the materials we use.How
long materials remain of utility, whether they
are easily recycled and how andwhat form they
are in when we eventually throw them away. What
we take from the environment around us, how we
manipulate and make materials out of what we take
and what we waste result in underlying molecular
flows that affect earth systems.
Problems in the global commons today include
heavy metals, halogen carbon double bond
compounds, CFCs too much CO2 etc.
16
Innovative New Materials - the Key to
Sustainability
The choice of materials in construction controls
emissions, lifetime and embodied energies, user
comfort, use of recycled wastes, durability,
recyclability and the properties of wastes
returned to the bio-geo-sphere.
There is no such place as away, only a global
commons
17
Sustainability Culture Technology
Increase in demand/price ratio for sustainability
due to educationally induced cultural drift.

Supply
Greater Value/for impact (Sustainability) and
economic growth
Equilibrium shift
ECONOMICS
New Technical Paradigms are required that deliver
sustainability. (TecEco and geopolymers.)
Demand
Increase in supply/price ratio for more
sustainable products due to innovative paradigm
shifts in technology.

Sustainability is where Culture and Technology
meet. Demand Supply
18
Huge Potential for Sustainable Materials in the
Built Environment

• The built environment is made of materials and is
  our footprint on earth.
• It comprises buildings and infrastructure.
• Construction materials comprise
• 70 of materials flows (buildings, infrastructure
  etc.)
• 40-45 of waste that goes to landfill (15 of
  new materials going to site are wasted.)
• Reducing the impact of the take and waste phases
  of the techno-process.
• Reducing emissions and other impacts during
  manufacture.
• Including carbon in materials so they become
  carbon sinks (eco-cements).
• including wastes fortheir physical properties
  aswell as chemical compositionso they become
  resources.

19
TecEco Technologies

• Silicate ? Carbonate Mineral Sequestration
• Using either peridotite, forsterite or serpentine
  as inputs to a silicate reactor process CO2 is
  sequestered and magnesite produced.
• Proven by others (NETL,MIT,TNO, Finnish govt.
  etc.)
• Tec-Kiln Technology
• Combined calcining and grinding in a closed
  system allowing the capture of CO2. Powered by
  waste heat, solar or solar derived energy.
• To be proved but simple and should work!
• Direct Scrubbing of CO2 using MgO
• Being proven by others (NETL,MIT,TNO, Finnish
  govt. etc.)
• Tec and Eco-Cement Concretes in the Built
  Environment.
• TecEco eco-cements set by absorbing CO2 and are
  as good as proven.

TecEco
EconomicunderKyoto?
TecEco
20
TecEco Kiln Technology

• Tec-Kiln technology will be the first non fossil
  fuel industrial process.
• variable energy input.
• Made from geopolymers.
• Suitable for the manufacture of MgO, CaO and
  metakaolin. Eventually Portland cement.
• Grinds and calcines at the same time.
• Runs 25 to 30 more efficiency.
• Theoretically capable of producing much more
  reactive MgO as well as metakaolin and other
  input materials for geopolymers.

21
TecEco Kiln Technology

• Captures CO2 for bottling and sale.
• To the oil industry (geological sequestration).
• Coca Cola?
• Can be run cyclicly as part of a major process to
  solve global CO2 problems.
• Will result in new markets for ultra reactive low
  lattice energy MgO (e.g. paper and environment
  industries).

TecEco plan to use geopolymer materials for the
kiln capable of withstanding high temperatures.
22
Drivers for TecEco Geopolymer Technology
Government Influence Carbon Taxes Provision of
Research Funds Environmental education
Consumer PullEnvironmental sentimentFear of
climate changeCostTechnical advantagesCompetiti
on
Huge Existing Markets Cement gt2 billion
tonnes. New markets e.g. Bingham mixtures for
robots, kilns, fireproof materials etc.
Producer PushThe opportunity cost of compliant
waste disposalProfitability and cost
recoveryTechnical meritResource
issuesRoboticsResearch objectives
The way forward is through solving problems in
niche markets and delivering sustainability.
23
TecEco Cement Concretes
More information at www.tececo.com
24
TecEco Cements
25
The Magnesium Thermodynamic Cycle
26
TecEco Formulations

• Tec-cements (Low MgO)
• contain more Portland cement than reactive
  magnesia. Reactive magnesia hydrates in the same
  rate order as Portland cement forming Brucite
  which uses up water reducing the voidspaste
  ratio, increasing density and possibly raising
  the short term pH.
• Reactions with pozzolans are more affective.
  After all the Portlandite has been consumed
  Brucite controls the long term pH which is lower
  and due to its low solubility, mobility and
  reactivity results in greater durability.
• Other benefits include improvements in density,
  strength and rheology, reduced permeability and
  shrinkage and the use of a wider range of
  aggregates many of which are potentially wastes
  without reaction problems.
• Eco-cements (High MgO)
• contain more reactive magnesia than in
  tec-cements. Brucite in porous materials
  carbonates forming stronger fibrous mineral
  carbonates and therefore presenting huge
  opportunities for waste utilisation and
  sequestration.
• Enviro-cements (High MgO)
• contain similar ratios of MgO and OPC to
  eco-cements but in non porous concretes brucite
  does not carbonate readily.
• Higher proportions of magnesia are most suited to
  toxic and hazardous waste immobilisation and when
  durability is required. Strength is not developed
  quickly nor to the same extent.

27
TecEco Cement Technology

• Portlandite (Ca(OH)2) is too soluble, mobile and
  reactive.
• It carbonates, reacts with Cl- and SO4- and being
  soluble can act as an electrolyte.
• TecEco generally (but not always) remove
  Portlandite using the pozzolanic reaction and
• TecEco add reactive magnesia
• which hydrates, consuming water and concentrating
  alkalis forming brucite which is another alkali,
  but much less soluble, mobile or reactive than
  Portlandite.
• In Eco-cements brucite carbonates

The consequences of need to be considered.
28
Strength with Blend Porosity
Tec-cement concretes
High Porosity
Eco-cement concretes
Enviro-cement concretes
High Magnesia
High PC
Tec cement concretes have more polymeric
species because they are much more alkaline
during the early plastic phase.
STRENGTH ON ARBITARY SCALE 1-100
29
Why Add Reactive Magnesia?

• To maintain the long term stability of CSH.
• Maintains alkalinity preventing the reduction in
  Ca/Si ratio.
• To remove water.
• Reactive magnesia consumes water as it hydrates
  to possibly hydrated forms of brucite.
• To raise the early Ph.
• Increasing non hydraulic strength giving
  reactions
• To reduce shrinkage.
• The consequences of putting brucite through the
  matrix of a concrete in the first place need to
  be considered.
• To make concretes more durable
• Because significant quantities of carbonates are
  produced in porous substrates which are affective
  binders.

Reactive MgO is a new tool to be understood with
profound affects on most properties
30
Tec-Cements Geopolymers
In the presence of water magnesium does not
appear to be an important network former in
silicate structures including geopolymers at room
temperature and this is probably because of its
high affinity for water which it seems to retain
even when it carbonates. There are however other
intriguing ramifications of adding reactive MgO.
More information at www.tececo.com
31
The Form of MgO - Overcoming Dogma

• In 1917 the US National Bureau of Standards (now
  the National Bureau of standards and Technology)
  and the American Society for Testing Materials
  established a standard formula for Portland
  cement which excluded MgO in any form.
• We now know that it is lattice energy that causes
  the difference between amorphous magnesia and
  periclase
• TecEco have proved that amorphous magnesia,
  having no lattice energy to overcome, is safe to
  use in water based binder systems.

32
The Form of MgO - Lattice Energy Destroys a Myth

• Magnesia, provided it is reactive rather than
  dead burned (or high density, crystalline
  periclase type), can be beneficially added to
  cements in excess of the amount of 5 mass
  generally considered as the maximum allowable by
  standards prevalent in concrete dogma.
• Reactive magnesia is essentially amorphous
  magnesia with low lattice energy.
• It is produced at low temperatures and finely
  ground, and
• will completely hydrate in the same time order as
  the minerals contained in most hydraulic cements.
• Dead burned magnesia and lime have high lattice
  energies
• Crystalline magnesium oxide or periclase has a
  calculated lattice energy of 3795 Kj mol-1 which
  must be overcome for it to go into solution or
  for reaction to occur.
• Dead burned magnesia is much less expansive than
  dead burned lime in a hydraulic binder
  (Ramachandran V. S., Concrete Science, Heydon
  Son Ltd. 1981, p 358-360 )

33
Tec-Cement Concrete Strength Gain Curve

• The use of tec-cement results in
• 20-30 greater strength or less binder for the
  same strength.
• more rapid early strength development even with
  added pozzolans.
• Straight line strength development for a long time

strength gain with less cement and added
pozzolans is of great economic and environmental
importance.
We have observed this sort of curve in over 300
cubic meters of concrete now
34
Tec-Cement Reactions
MgO H2O gt Mg(OH)2.nH2O - water consumption
resulting in greater density and higher
alkalinity. Higher alkalinity gt more reactions
involving silica alumina. Mg(OH)2.nH2O gt
Mg(OH)2 H2O slow release water for more
complete hydration of PC MgO Al H2O gt
3MgO.Al.6H2O ??? equivalent to flash set?? MgO
SO4-- gt various Mg oxy sulfates ?? yes but
more likely ettringite reaction consumes SO4--
first. MgO SiO2 gt MSH ?? Yes but high
alkalinity required. Strength??
We think the reactions are relatively independent
of PC reactions
35
Non hydration Reactions in Tec-Cement Concretes?

• MgO H2O gt Mg(OH)2.nH2O - water consumption
• Increases density.
• Raises the alkalinity during the early plastic
  stage.
• Better pozzolanic reactions, surface hydrolysis
  and re-bonding as well as the formation of more
  polymeric not necessarily hydraulic species.
• Resulting mineralization more similar to Roman
  cement concretes that contained more Mg and more
  polymeric species.

36
Tec-Cement pH Curves
37
Conjecture

• Why does Mg keep turning up in discussion of
  ancient mineral systems (Egyptians, Mesopotamians
  and Romans)??
• Maybe sepiolite (polygorskite with Al?) are
  carrier minerals that break down as the
  alkalinity rises delivering soluble and mobile
  SiO2 and Al2O3 for reactions forming more
  polymeric minerals.

This idea emerged over too many drinks with
Herbert Baier of PCI (part of Degussa) on the
29th June in Saint Quentin, France. Its
conjecture, interesting and not completely daft.
38
Role of Mg in Geopolymerism??!

• Mg4Si6O15(OH)2.6H2O (sepiolite) clay sodium or
  potassium salt gt Geopolymer (Si-O-Al-O-Si ??)
  brucite more sepiolite??
• or
• Sepiolite clay H2O CO2 OH-
• Geopolymer sepiolite salt??

Sepiolite precipitates from salty alkaline waters
in arid environments and was available to the
Egyptians. Does explain role of Mg in Egyptian
cements.
39
Strength Development in Tec-Cements.

• Reactive magnesia requires considerable water to
  hydrate resulting in
• A significantly lower voids/paste ratio i.e.
  denser, less permeable concrete.
• Higher early pH initiating more effective
  silicification reactions?
• The Ca(OH)2 normally lost in bleed water is used
  internally for reaction with pozzolans.
• Super saturation of alkalis caused by the removal
  of water?

Could the role of added reactive magnesia be to
consume water like the ettringite reaction in PC
concretes. This property could be useful with
geopolymers to overcome the viscosity problem.
40
Water Reduction During the Plastic Phase?
Water is required to plasticise concrete for
placement, however once placed, the less water
over the amount required for hydration the
better. Magnesia consumes water as it hydrates
producing solid material.
Less water results in increased density and
concentration of alkalis - less shrinkage and
cracking and improved strength and durability.
41
High Alkalinity Common to Both Hydraulic and
Geopolymer Systems gt Better Reactions.

• For more effective reactions in hydraulic
  concretes like PC and in geopolymer concretes
  high alkalinity is required.
• To achieve high alkalinity it is necessary to not
  add too much water this results in higher
  viscosity.
• To place concretes low viscosity is required.
• Tec-cement concretes achieve high alkalinity by
  internal water removal.
• The dichotomy between viscosity and ease of
  placement defines much of the current research on
  geopolymers and for that matter in relation to
  additives for PC.
• Depending on the level of alkalinity reached,
  many of the particles of fly ash or dehydrated
  clay (Kandoxi) polymerise, react at the surface
  only (hydrolyse and re-bond) or remain as
  micro-aggregates.

42
Adding Reactive MgO

• Portland cements stoichiometrically require
  around 23 -25 water for hydration yet we add
  approximately 45 to 50 at cement batching plants
  to fluidise the mix sufficiently for placement.
• If it were not for the enormous consumption of
  water by tri calcium aluminate as it hydrates
  forming ettringite in the presence of gypsum,
  concrete would remain as a weak mush and probably
  never set.
• 26 moles of water are consumed per mole of tri
  calcium aluminate to from a mole of solid
  ettringite. When the ettringite later reacts with
  remaining tri calcium aluminate to form
  monosulfoaluminate hydrate a further 4 moles of
  water are consumed.
• The addition of reactive MgO achieves water
  removal in a similar way.
• Can reactive MgO be used to get over the
  viscosity issue in geopolymers?
• Would this be cheaper than using super
  plasticisers?

43
Adding Reactive MgO to Geopolymers

• It is not possible to add water to geopolymers.
  If water were add the alkalis would be diluted,
  the pH would fall and the mix would not set as
  unlike the setting of Portland cement concretes
  there is no reaction that consumes water. On the
  contrary water is expelled.
• Reactive magnesia is a water removal tool and may
  be useful as an adjunct to assist with the
  viscosity problem.
• Most people researching geopolymers seem to be
  trying various super, duper, hyper, blah blah
  plasticiser molecules to see if they can be used
  to fluidise the mix sufficiently.
• The water removal mechanism of magnesia and its
  plasticising properties may be useful as a
  totally different approach to get over the
  viscosity issue. There is obviously more work to
  do pending funding but could it be that the best
  features of geopolymeric and hydraulic cements
  can be combined?
• There are more polymeric species in Roman cements.

44
Non Newtonian Rheology
The strongly positively charged small Mg atoms
attract water (which is polar) in deep layers
affecting the rheological properties and making
concretes less sticky with added pozzolan
It is not known how deep these layers get
Etc.
Etc.
Ca 114, Mg 86 picometres
45
MgO Changes Surface Charge as the Ph Rises







This could be the reason for the greater tensile
strength displayed during the early plastic phase
of tec-cement concretes.



Cement
MgO
Sand











Mutual Repulsion
gt
Ph 12 ?




-


-

-
Cement
MgO
-
Sand

-



-
-



Mutual Attraction
46
Tec-Cement Tensile Strength
Graphs by Oxford Uni Student
Tensile strength is thought to be caused by
change in surface charge on MgO particles from
ve to ve at Ph 12 and electrostatic attractive
forces
47
Rheology

• TecEco concretes and mortars are
• Very homogenous and do not segregate easily. They
  exhibit good adhesion and have a shear thinning
  property.
• Exhibit Bingham plastic qualities and react well
  to energy input.
• Have good workability.
• TecEco concretes with the same water/binder ratio
  have a lower slump but greater plasticity and
  workability.

• A range of pumpable composites with Bingham
  plastic properties will be required in the future
  as buildings will be printed. (Robotics)

48
Technical Comparisons Geopolymers and Tec-Cement
Concretes
49
Technical Comparisons Geopolymers and Tec-Cement
Concretes (2)
50
Other Comparisons Common Problems
51
TecEco and Geopolymer Groups

• Mutual response to government
• Changing standards to performance based.
• Policy issues
• Procurement policies designed to foster new more
  sustainable materials technologies.
• Funding for sustainable new materials.
• Mutual promotion of sustainability.
• Educational the buying public
• Counter subversive tactics by the PC lobby

There are definitely benefits to co-operation
between the two emerging technologies e.g. EU
research funding.
52
TecEco and the PC Cement Industry

• The PC industry should
• Spend a little more money on research to move
  cementitous composites into better market space.
• Spend a little less on litigation, remediation
  and arbitration because of the imperfect material
  they have.

Worth thinking about in context of carbon taxes?
53
TecEco Cement Implementation Summary
54
High Performance-Lower Construction Costs

• Less binders (OPC magnesia) for the same
  strength.
• Faster strength gain even with added pozzolans.
• Elimination of shrinkage reducingassociated
  costs.
• Tolerance and consumption of water.
• Reduction in bleed water enables finishing of
  lower floors whilst upper floors still being
  poured and increases pumpability.
• Cheaper binders as less energy required
• Increased durability will result in lower
  costs/energies/emissions due to less frequent
  replacement.
• Because reactive magnesia is also an excellent
  plasticiser, other costly additives are not
  required for this purpose.
• A wider range of aggregates can be utilised
  without problems reducing transport and other
  costs/energies/emissions.

Foolproof Concrete?
55
TecEco Concretes - Lower Construction Costs (2)

• Homogenous, do not segregate with pumping or
  work.
• Easier placement and better finishing.
• Reduced or eliminated carbon taxes.
• Eco-cements can to a certain extent be recycled.
• TecEco cements utilise wastes many of which
  improve properties.
• Improvements in insulating capacity and other
  properties will result in greater utility.
• Products utilising TecEco cements such as masonry
  and precast products can in most cases utilise
  conventional equipment and have superior
  properties.
• A high proportion of brucite compared to
  Portlandite is water and of Lansfordite and
  nesquehonite compared to calcite is CO2.
• Every mass unit of TecEco cements therefore
  produces a greater volume of built environment
  than Portland and other calcium based cements.
  Less need therefore be used reducing
  costs/energy/emissions.

56
Summary

• Simple, smart and sustainable?
• TecEco cement technology has resulted in
  potential solutions to a number of problems with
  Portland and other cements including shrinkage,
  durability and corrosion and the immobilisation
  of many problem wastes and will provides a range
  of more sustainable building materials.
• The right technology at the right time?
• TecEco cement technology addresses important
  triple bottom line issues solving major global
  problems with positive economic and social
  outcomes.

57
TecEco Doing Things
58
The Use of Eco-Cements for Building Earthship
Brighton
By Taus Larsen, (Architect, Low Carbon Network
Ltd.) The Low Carbon Network (www.lowcarbon.co.uk)
was established to raise awareness of the links
between buildings, the working and living
patterns they create, and global warming and aims
to initiate change through the application of
innovative ideas and approaches to construction.
Englands first Earthship is currently under
construction in southern England outside Brighton
at Stanmer Park and TecEco technologies have been
used for the floors and some walling.
Earthships are exemplars of low-carbon design,
construction and living and were invented and
developed in the USA by Mike Reynolds over 20
years of practical building exploration. They are
autonomous earth-sheltered buildings independent
from mains electricity, water and waste systems
and have little or no utility costs. For
information about the Earthship Brighton and
other projects please go to the TecEco web site.
59
Repair of Concrete Blocks. Clifton Surf Club
The Clifton Surf Life Saving Club was built by
first pouring footings, On the footings block
walls were erected and then at a later date
concrete was laid in between. As the ground
underneath the footings was sandy, wet most of
the time and full of salts it was a recipe for
disaster. Predictably the salty water rose up
through the footings and then through the blocks
and where the water evaporated there was strong
efflorescence, pitting, loss of material and
damage.
The TecEco solution was to make up a formulation
of eco-cement mortar which we doctored with some
special chemicals to prevent the rise of any more
moisture and salt. The solution worked well and
appears to have stopped the problem.
60
Mike Burdons Murdunna Works
Mike Burdon, Builder and Plumber. I work for a
council interested in sutainability and have been
involved with TecEco since around 2001 in a
private capacity helping with large scale testing
of TecEco tec-cements at our shack. I am
interested in the potentially superior strength
development and sustainability aspects. To date
we have poured two slabs, footings, part of a
launching ramp and some tilt up panels using
formulations and materials supplied by John
Harrison of TecEco. I believe that research into
the new TecEco cements essential as overall I
have found

• The rheological performance even without
  plasticizer was excellent. As testimony to this
  the contractors on the site commented on how easy
  the concrete was to place and finish.
• We tested the TecEco formulations with a hired
  concrete pump and found it extremely easy to pump
  and place. Once in position it appeared to gel
  up quickly allowing stepping for a foundation to
  a brick wall.
• Strength gain was more rapid than with Portland
  cement controls from the same premix plant and
  continued for longer.
• The surfaces of the concrete appeared to be
  particularly hard and I put this down to the fact
  that much less bleeding was observed than would
  be expected with a Portland cement only
  formulation

61
Tec-Cement Slab Whittlesea, Vic. Australia

• On 17th March 2005 TecEco poured the first
  commercial slab in the world using tec-cement
  concrete with the assistance of one of the larger
  cement and pre-mix companies.
• The formulation strategy was to adjust a standard
  20 MPa high fly ash (36) mix from the company as
  a basis of comparison.
• Strength development, and in particular early
  strength development was good. Interestingly some
  70 days later the slab is still gaining strength
  at the rate of about 5 MPa a month.
• Also noticeable was the fact that the concrete
  was not as "sticky" as it normally is with a fly
  ash mix and that it did not bleed quite as much.
• Shrinkage was low. 7 days - 133 micro strains, 14
  days - 240 micro strains, 28 days - 316 micros
  strains and at 56 days - 470 microstrains.