Lafarge The Production of extended cements & the impact on concrete Durability

Courtesy of Patrick Rimoux (architecte)

Production of extended cements

& the impact on concrete

durability

2

AGENDA

1. Introduction

2. About Lafarge

3. The Lafarge Specifier Handbook

4. Cement manufacturing & extenders

5. Soil Stabilization

6. Physical deformations on concrete

7. Chemical deformations on concrete

8. Masonry, Mortars & Plasters

9. Ready-mixed Concrete Products

3

ABOUT LAFARGE

4 4

Lafarge is the world leader in building materials

Number 1 in Cement

Number 2 Aggregates and Concrete

Number 3 in Gypsum

15,2 billion Euros in Sales turnover

68 000 employees

Present in 64 countries

Almost 130 million Euros dedicated to research,

product development and industrial process performance

improvement annually. With about 500 dedicated people world wide.

LAFARGE INTERNATIONAL

5

LAFARGE IN SOUTH AFRICA

Safety is our number 1 priority

Lafarge South Africa has 2500 employees

All four divisions present in South Africa

Cement

Aggregates

Concrete

Gypsum

First in the industry to sign a BBBEE deal in South Africa valued at 1.1 billion Rand

Internationally recognized HIV/Aids campaign in place

First cement producer to become a member of the Green Building Council

5

6

LAFARGE CEMENT FACILITIES (SOUTH AFRICA)

Manufacturing facility in Lichtenburg

Biggest in the Southern Africa

Capacity of 3,3 million tons cement

Grinding facility in Richards Bay and Randfontein

Strategic depots in

Kaalfontein

Polokwane

Quality Department of Southern Africa

One of the largest and most respected SANAS

accredited Civil Engineering testing facilities in

South Africa

Complies with ISO/IEC 17025

17 year track record of continuous accreditation

Boasting 35 accredited test methods

6

7

THE LAFARGE SPECIFIER HANDBOOK

8

ABOUT THE MANUAL

The Lafarge Specifier Handbook has been designed to provide our

specifiers & engineers with application specific quick reference cement &

readymix guide

In Volume 1 we cover the needs and solutions for each application,

including:

1. Roads & Earthworks

2. Civil Construction

3. Concrete Product Manufacturing

4. Masonry Applications

5. Specialised Applications

6. Readymix Concrete

We have also included the SANS 50197-1: Common Cement Table & a

number of case studies for your reference

Dr Reinhold Amtsbüchler,

Pr Engineer and Manager

Quality Department Southern Africa

Lafarge South Africa

“ While maintaining our proud track record of technical excellence, our skills are directly

and indirectly employed to satisfy today’s cement market needs and to anticipate the

future needs of our customers.

This handbook is intended to provide a convenient guide for engineers and specifiers

when selecting quality, reliable performance cements for specific applications.”

9

CEMENT MANUFACTURING

Quintin Wolmarans

10

WHAT IS CEMENT?

Portland cement is an extremely fine grey powder manufactured

from some of the earth's most common minerals. It's the glue that

binds sand and gravel together into the rock-like mass we know as

concrete.

11

Quarrying

And

Crushing

Pre –blending

Storage

Raw Milling &

Homogenisation

Burning Cement Milling

Packing &

Despatch

CEMENT MANUFACTURING

12

CEMENT CONSTITUENTS

The following materials are milled & blended before entering the kiln:

Limestone -CaCO3

Alumina source -Al2O3 (PozzSand, Bauxite, etc)

Iron ore –Fe2O3 (Magnetite)

Silica source –SiO2 (PozzSand)

These materials are heated to temperatures of1450°C to produce a partially molten combination called clinker.

Clinker is then inter-ground with Gypsum to create cement powder.

Other Constituents may be added at the mill (Limestone, Fly Ash, Slag, etc)

13

Quarry Crusher Limestone

Additives

Pozzsand

Bauxite

Magnetite

Raw Mill

Kiln feed Silo

To Raw mix

preperation

Mining of limestone requires the use of drilling and blasting techniques.

The blasting techniques use the latest technology to insure vibration, dust,

and noise emissions are kept at a minimum. Blasting produces materials in a

wide range of sizes from approximately 1.5 meters in diameter to small

particles less than a few millimeters in diameter.

Material is loaded at the blasting face into trucks for transportation to the

crushing plant. Through a series of crushers and screens, the limestone is

reduced to a size less than 100 mm and stored until required.

Limestone is mined from different faces in the quarry to produce a blend

of limestone that complies to chemical requirements set by the plant to

produce quality clinker

The limestone is then transported to site where it is blended and stored

on a stockpile until needed for raw milling

LIMESTONE QUARRY

14

Quarry Crusher Limestone

Additives

Pozzsand

Bauxite

Magnetite

Raw Mill

Kiln feed Silo

To pre-heater

Limestone is proportioned with other

corrective materials and then grinded in the

raw mill to a fine powder called kiln feed.

Limestone on its own do not contain all the

elements needed to form good quality clinker.

Limestone provide for CaCO3 the main

component for clinker formation.

Pozzsand and Bauxite is added to introduce

SiO2 & Al2O3 and

Magnetite is added to introduce Fe2O3

When proportioned correctly they will combine in the kiln

to form the following main components in clinker:

C3S (Alite) 3CaO.SiO2 Tricalcium Silicate

C2S (Belite) 2CaO.SiO2 Dicalcium Silicate

C3A 3CaO.Al2O3 Tricalcium Aluminate

C4AF 4CaO.Al2O3.Fe2O3 Tetracalcium Alumino Ferrite

RAW MILLING

15

Stack

Filter

Cooler

CLINKER

Fuel

Preparation

Preheat Tower Kiln

To Cement mill about 100°C-600°C:

free water evaporation

800-1050°C:

CaCO3 CaO + CO2

> 800°C

- iron oxide combines with alumina & lime to form C4AF

- then, the remaining alumina will react with lime to form C3A

- silica and lime start to form C2S

> 1200°C

- formation of C3S (C2S reacts with remaining lime)

> 1338°C:

C4AF and C3A generate the liquid phase

accelerates solid/solid chemical reactions

(silica/ lime)

contributes to burnability

Quenching to set clinker reactions:

prevent C3S reversion to C2S

g + C

Kiln feed

CLINKER FORMATION

16

Gypsum

Finish Mill Cement Silo’s

Additions Limestone, slag etc

Fly ash Clinker from clinker

storage

Cement Milling

Clinker is grinded in the cement mill to a fine powder to increase the surface area

available for reaction with water. C3S + H2O = HCS +CaOH

This process is called hydration.

The finer the cement is milled the higher the strength of the cement will be.

During the hydration process C3A will also react with water and cause the cement to

set immediately. This is called Flash set.

To prevent this from happening Gypsum (CaSO4.2H2O) is added to the cement to

form a layer around the C3A crystals to slow down the reaction with water.

To create cement with different properties for different applications than normal

cement, Fly ash or slag or both can be added to the cement.

Each of these additives or extenders will give the cement enhanced properties that will

make it suitable for a wide range of applications

17

16 µ

Alkaline

sulfates

Belite

Free lime

Alites

Aluminates and

aluminoferrites

• A cement particle is:

• heterogeneous

• multiphase

All these phases will hydrate

HYDRATION OF CEMENT

18

• C3S + water = Hydrated calcium silicates + portlandite

CSH {C3S2H3 } CH {Ca(OH)2 }

2C3S + 6H C3S2H3 + 3CH + heat

• C2S + water = CSH + CH The same as C3S but much more slowly

2C2S + 4H C3S2H3 + CH + heat

• CSH • Not properly crystallised

• Chemical composition depending on hydration conditions

CALCIUM SILICATES HYDRATION

19

1 µm

CSH

CH

CSH & PORTLANDITE FORMATION

20

• C3A + water =

Hydrated calcium aluminates

C3A + C + nH C4AH11<n<15 (mainly 13)

Ettringite (when sulfate existing)

C3A+ 3C + 3S + 32H C3A(CS)3H32

• C4AF + water =

The same as C3A but much more slowly

F is reacting like A

• Free lime + water = Ca(OH)2 Portlandite

C + H => CH

!! Dangerous due to expansion if in excess

ALUMINATES & FREE LIME

21

THE 5 COMMON TYPES OF CEMENT

SANS 50197

CEM I Portland Cement

CEM II Portland “Composite” Cement

CEM III Blast furnace Cement

CEM IV Pozzolanic Cement

CEM V Composite Cement

22

CEM II / B - M (V-S) 32.5N

Cement family:

CEM I : Portland cement

CEM II : composite Portland cement

CEM III : blast furnace cement

CEM IV : pozzolanic cement

CEM V : slag and ash cement

CEMENT NAMING (EXAMPLE)

23

CEM II / B - M (V-S) 32.5N

Cement family




CEM IV : pozzolanic cement


Quantity of main constituents

other than

clinker (as a % added)

A: from 6 to 20%

B: from 21 to 35 %

C: from 36 to 65 %

(slag for EM III)


24

CEM II / B - M (V-S) 32,5N

Cement family




CEM IV : puzzolanic cement



other than


A: from 6 to 20%

B: from 21 to 35 %

C: from 36 to 65 %

(slag for EM III)

Cement with at least

2 main constituents

other than clinker


25

CEM II / B - M (V-S) 32.5N

Cement family

CEM I: Portland cement

CEM II: composite Portland cement

CEM III: blast furnace cement

CEM IV: puzzolanic cement

CEM V: slag and ash cement


other than


A: from 6 to 20%

B: from 21 to 35 %

C: from 36 to 65 %

(slag for EM III)


2 main constituents

other than clinker

Names of the main constituents

S: Aggregated slag from blast furnaces

V: silicious fly ash

W: calcic fly ash

L or LL: limestone (depending on the percentage

of organic carbon)

D: silica fume

P or Q: pozzolanic materials

T: Pre-fired shale


26

CEM II / B - M (V-S) 32.5N

Cement family







other than


A: from 6 to 20%

B: from 21 to 35 %

C: from 36 to 65 %

(slag for EM III)


2 main constituents

other than clinker


S: aggregated slag from blast furnaces


W: calcic fly ash


of organic carbon)

D: silica fume

P or Q: puzzolanic materials

T: Pre-fired shale

strength classes (minimum characteristic strength at

28 days, expressed in MPa):

32.5 or 42.5 or 52.5


27

CEM II / B - M (V-S) 32,5N

Cement family







other than


A: from 6 to 20%

B: from 21 to 35 %

C: from 36 to 65 %

(slag for EM III)


2 main constituents

other than clinker


S: aggregated slag from blast furnaces


W: calcic fly ash


of organic carbon)

D: silica fume

P or Q: puzzolanic materials

T: Pre-fired shale

strength classes (minimum characteristic strength at

28 days, expressed in MPa):

32.5 or 42.5 or 52.5

strength sub-classes (minimum characteristic strength

after 2 days, expressed in MPa).

N: Normal

R: Quick


28

CEMENT NAMING (SANS 50196 TABLE)

Strength Class

Compressive Strength , MPa

Early Strength

Standard Strength

2 days

7 days

28 days

32,5 N

-

> 16,0

> 32,5

< 52,5

32,5 R

> 10,0

-

42,5N

> 10,0

-

> 42,5

< 62,5

42,5R

> 20,0

-

52,5 N

> 20,0

-

52,5

-

29

CEMENT EXTENDERS

Fresh Concrete

Improves workability and reduces water

requirement for a given slump.

Slightly retards setting.

Hardened Concrete

Slightly reduces rate of strength development.

Increase later strength (eg.90 days).

Reduce rate of chloride diffusion through concrete.

Refine pore structure and reduce permeability.

Inhibits ASR reaction.

Improves sulphate resistance.

Reduce rate of heat generation

from cementing reactions.

New specification SANS 50450-1:2011

Fly ash / Pulverized fuel ash (PFA)

30

Fresh Concrete

May improve workability slightly.

Retards setting slightly.

Hardened Concrete

Slows development of strength.

Increase later strength, (e.g.. 90 days)

Refines pore structure and reduce permeability.

Increase rate of carbonation.

Retards alkali-silica reactions.

Binds chlorides and reduce chloride induced corrosion of embedded steel.

Reduce rate of heat generation caused by cementing reactions.


Ground granulated blast furnace slag (GGBS)

Blast-

furnace

slag

floating

Cast-

iron

co

ke

Iron

ore Melting agent

=

1450°C

CEMENT EXTENDERS

31

CEMENT EXTENDERS

Fresh Concrete

Reduces workability.

Increases cohesiveness.

Reduces bleeding significantly.

Hardened Concrete

Increased strength.

Reduces permeability.


Condensed Silica fume (CSF)

32

LAFARGE PRODUCT RANGE

3

2

CEM IV/B-V 32,5R CEM II/A-M (V-L) 42,5R CEM II/B-M (V-S) 32,5N CEM II/A-V 52,5N

33

SOIL STABILISATION

Mike Fisher

34

SOIL STABILISATION

Soil is important engineering material used in:

Foundations

Embankments

Roads

Numerous other situations

When the soil has unsuitable properties, the Engineer has the following alternatives:

Modify the design, to suit the insitu material

Replace the insitu material with suitable material

Upgrade the properties of the insitu material

The latter is known as stabilisation, and one of the most effective methods of

stabilisation is to mix the soil with cement and re-compact it

35

SOIL STABILISATION

Soil is a complex and variable material, and the result of treatment depend

on the properties of the particular soil.

These effects must be understood and the testing and design process has

to achieve the design objectives.

Soil Properties which concern the engineer include

Strength and resistance to deformation (stiffness)

Volume stability

Durability (performance of strength stiffness)

Permeability

36

SOIL STABILISATION

Most soils have considerable strength when compacted at optimum

moisture content, but strength can be lost if moisture content alters

significantly

Granular soils become friable when dry

Cohesive soils become plastic at high moisture contents

Soils containing clay undergo movements as moisture content changes

Shrink during drying

Expand when moisture content increase

37

SOIL STABILISATION

When the pavement is designed to carry traffic, the designer requires a pavement that

acquires no permanent deflections from large numbers of repeated instantaneous

loads.

The soil properties that allows for deflection recovery is stiffness and strength.

When a load is applied to a soil surface, the stress causing deflection diminishes at

increasing depth below the surface, due to the effect of the load spreading over a

much larger area.

Therefore the required strength and stiffness reduces as the depth below increases.

Strength has two major components:

Cohesion , in soils containing clay, and is dependant on clay content, density

and moisture condition.

Internal friction, property of granular soils, relating to particle size, grading,

particle shape, density and degree of compaction

38

SOIL STABILISATION

Most soils, when mixed with cement and compacted, will be stronger than if

compacted without cement.

Exceptions are :

Organic soils

Soils with high salinity

Soils with high sulphate content

Soils with PI of above 18%

The strength of the stabilised soils depend primarily on the cement content and the

degree of compaction

Moisture content on time of test is also important, particularly in soils with high clay

content.

39

SOIL STABILISATION

Effects of Cement stabilisation:

Initially during the hydration process a series of nuclei is developed, this develops into

a lattice of hydrated cement in the soil, yielding strength.

Associated with this process is the process of liberating lime witch has strengthening

effects on the minerals in certain clays.

The extend of these effects will depend on the cement content, and the nature of the

soils involved.

And the benefits from the barely observable cohesion and loss of plasticity, to the

strength an durability properties.

40

SOIL STABILISATION

Shrinkage and Cracking of cement stabilised soil:

At low cement concentrations a soil with a relative high clay content retains the

property of the shrinkage on drying and softening when saturated.

Hydrated cement paste also shrinks, but to a lesser extend.

The volume of shrinkage in clay soils is reduced as the cement content increase.

Shrinkage of granular material may increase, as the cement content increase.

Tendency of block cracking depends on:

Extend of shrinkage

Tensile strength at time of shrinkage

Shrinkage potential can be reduced by reduction of the density

Adjustment of initial moisture content.

Excessively strong mixes can lead to wide spaced crack patterns, of sufficient crack

width to rupture the surface seal.

This cracking and ruptured seal, allows for moisture ingress and leads to softening of

the sub-grade, leading to vertical cracking, that allows for movement of the material

on either side

41

ROAD CONSTRUCTION

Road construction will continue to be one of the mainstay sectors of the

civil construction market.

The market currently comprises of:

15% - 20% new road building activity

The balance falls into road rehabilitation

SANRAL estimates backlogs in maintenance & rehabilitation on provincial

and municipal roads at R64 billion

31% of total provincial surfaced road network is in a poor and very poor

condition compared to 10% benchmark of the World Bank

Average of only 25km per year was rehabilitated since the year 2000

42

ROAD CONSTRUCTION

Road construction will continue to be one of the mainstay sectors of the

civil construction market.

The market currently comprises of:

15% - 20% new road building activity

The balance falls into road rehabilitation

SANRAL estimates backlogs in maintenance & rehabilitation on provincial

and municipal roads at R64 billion

31% of total provincial surfaced road network is in a poor and very poor

condition compared to 10% benchmark of the World Bank

Average of only 25km per year was rehabilitated since the year 2000

43

SOIL STABILISATION

Stabilization products are designed to reduce the plasticity index (P.I.)

of a wide range of paving materials.

Enhance the strength of various road construction materials.

Composite cements modify moderate soils similar to lime

SOIL STABILISATION PERFORMANCE CHARACTERISTICS

Strength: soil strength and bearing capacity is increased.

Volume stability: controls the swell and shrinkage characteristic caused

by moisture changes

Durability: increases resistance to erosion, weathering or traffic loading

44

SOIL STABILIZATION - PRODUCTS

CEM II/ B-M (V-S) 32,5N

Slower strength gain

cementitious binder

Higher ultimate strength

Open time: 300 minutes (Cement only)

CEM IV/ B-V 32,5R

Higher early rate of strength with

higher ultimate strengths

Open time: 210 minutes

(Cement only)

45

CEMENT USAGE IN ROAD STABILISATION

Based on an analysis of major road projects, cement usage in road

stabilisation is about 1 – 3% of project value. Examples of consumption

estimates by a large contractor and SANRAL are given below.

Estimated Cement Consumption (Sanral Projects)

Source: Sanral

0

2

4

6

8

10

12

2008/09 2009/10 2010/11 2011/12 2012/13

To

tal P

roje

ct V

alu

e (

R B

illi

on

)

0

20000

40000

60000

80000

100000

120000

140000

160000

180000

Ce

me

nt

Co

nsu

mp

tio

n (

To

ns)

1.5 – 1.8% of Project Value

46

THE STOLTZ SOLUTION

Lafarge offers contractors a unique spreading solution for roadbinder

cements & alternative stabilising materials with its state-of-the-art Stoltz

Site Spreader.

The first of its type in Africa, the spreader achieves impressive and rapid

application rates.

Radar controlled automated application provides more accurate, even

spreading, resulting in savings in material and time

47

BENEFITS

Control your own spreading schedule

Flexible working time

Consistent spreading, reducing risk of failure

Increased productivity based on speed of application

Reduced contingency margins based on efficient spreading rate

Competitive qualitative advantage for pricing tenders

48

MOVE FROM THIS....

49

...TO THIS

Consistent spread

Dust reclaimer

Reduce labour cost

Silo configuration

34t Capacity

Independent Engine

Digital Rate Controller

with radar

50

LABORATORY WORK

Laboratory work based on the Polokwane ring road material.

Material was used to conduct full stabilization evaluations using

Roadcem

Atterburg Limits Stabiliser Type % LL PL PI – 1 day

Before Stabilisation Neat 0% 26 20 6

After Stabilisation Roadcem 2%

4%

6%

25

34

31

25

29

31

0

NP

NP

51

LABORATORY COMPACTION DATA

EFFORT UCS (Mpa) Average ITS (KPa) Result

2% 100

90

3.6

2.1

320.0

254.0

4% 100

90

6.5

4.2

896.0

672.0

6% 100

90

8.3

7.1

706.0

635.0

LABORATORY WORK

52

LAFARGE ROAD PROJECTS: CURRENT AND COMPLETED

5

2

Client Contractor Project Product Engineers Province

SANRAL Esor Franki N4 Mooinooi Roadcem UWP NWP

TRAC WBHO N4 Middleburg Roadcem Vela VKE

(SMEC)

MPU

SANRAL Steffanutti

Stocks

N12 east

Driefontein

Roadcem Vela VKE

(SMEC)

NWP

SANRAL Roadcrete

Africa

N2 Piet Retief Roadcem Vela VKE

(SMEC)

MPU

SANRAL Roadcrete

Africa

Amersfoort Roadcem Bigen Africa MPU

SANRAL KPMM N14

Carltonville

Roadcem Aurecon NWP

SANRAL Superway R37 Lydenberg Roadcem Goba MPU

SANRAL Concor Simon

Vermooten

Roadcem SSI PTA

53

PHYSICAL DEFORMATION OF CONCRETE

Roelof Jacobs

54

CONCRETE

Deformation of concrete

Elasticity

Creep

Shrinkage

55

PROPERTIES OF CONCRETE

FOR THE DESIGNER

Designers of structures are concerned with:

Safety, Serviceability and Durability

Safety:

Time dependant strains, may not change the load barring capacity of a

member, at failure.

When stability is an issue, creep could play a role in failure load.

This would lead to reduced safety of the structure.

Serviceability:

Deflections and cracking plays the biggest part in serviceability.

This has impact on both short and long term deflections.

Durability:

This has the biggest impact on Economy of the structure

56

DEFORMATION OF CONCRETE

Influences on deformation:

57

Factors affecting E-Modules

Factors affecting E-modules are strength of the cement paste.

Stiffness of the aggregate.

Aggregate cement paste interface.

The stiffer the individual phases the higher the E-moduli will be, and the

lower the long term movement of the concrete.

Typically the paste E-moduli will vary from 5 to 25 GPa dependant on

w/c ratio

Degree of hydration

Air content

ELASTICITY OF CONCRETE

58

Structural implications

Importance of E-modules depends on the sensitivity of the structure to

deformations.

Where deflections are critical or secondary cracking is unacceptable E-

Modules predictions becomes important.

In some cases lower E-Modules may be required, where cracking due to

restraint movement are to be avoided.

E-Modules in high strength concrete are dependant on the coarse

aggregate rather than on the compressive strength.


59


60


Powercrete Plus 42,5R and Civilcrete 32,5R, are extended with Fly Ash.

The Pozzolanic reaction produces additional Calcium Silicate hydrate

gel, to fill pore spaces leading to a denser matrix, and reducing

permeability of the concrete

Fly ash incorporation leads to increased paste volume, improving the

Aggregate / Cement paste interface.

Lower water demand for given workability, compared to CEM I cements.

Early age E-moduli of fly ash concrete could be lower which is beneficial

to minimise crack development.

61

CREEP OF CONCRETE

What is Creep

Defined as the time dependant increase in strain of a solid body under

constant / controlled stress.

Could also manifest as a relaxation stress under constant strain.

62

CREEP OF CONCRETE

What is the implications of creep

Creep impacts on the Ductility of the structure.

Could be beneficial

Relieve stress caused by differential structural movements

Restraint shrinkage

Mostly detrimental to structures due to

Increased deflections, resulting in cracking

Loss of pre-stress

Buckling of columns

63

CREEP OF CONCRETE

Creep of concrete is the increased strain under sustained constant

stress.

64

CREEP UNDER CONSTANT STRESS

An applied compressive stress of

approx 40% of compressive

strength, creep would be considered

to be linear proportional to stress

65

CREEP UNDER CONSTANT STRESS

Characteristics of creep

Creep occurs at all stress levels, but mechanisms are different at higher

stress levels, above 40% of short term strength.

Concrete is heterogeneous in nature, leading to substantial stress

concentrations in the matrix.

Micro cracks will form in the matrix between aggregate and cement paste.

These micro-cracks will grow with sustained / increased external loading.

This leads to the additional component of creep at high stress levels

66

BASIC CREEP VS DRYING CREEP

Creep is simply considered to be

the deformation under load, in

excess of elastic strain and free of

shrinkage strain.

Basic Creep:

Creep that occurs when there is no

moisture movement between

concrete and the environment it is

in.

Drying Creep:

Additional creep that occurs when

concrete is drying while under

stress.

67


Structural effects of creep

Creep will cause redistribution of stresses in concrete, this could lead to

deflections.

Columns could undergo redistribution of stresses, stresses on steel is

increased and may even become very large leading to buckling of the

columns.

This is where sufficient number of ties and adequate cover to steel plays a

role in creep.

Creep deflections may also lead to instability of arched structures.

Creep at stress levels above 70% of short term compressive strength, the

micro cracks formed at the aggregate cement interface may spread and

propagate to cause complete breakdown.

This would lead to time dependant failure.

68


Creep mechanisms

Recoverable creep

Diffusion of water from areas of hindrance to areas of non hindrance,

reduce the swelling pressure on the pore water, leading to a reduction of

inter partial spacing.

Diffusion of water from high to low pressure areas cause gradual load

transfer from liquid to solid phases in the matrix.

The removal of inter layer to inter layer water, under the action of external

load, leading to reduction of layer thickness.

Irrecoverable creep

Weakening of the interlayer particle bonds, facilitating a relative sliding of

the layers.

Displacement of the gel layers relative to each other (breaking down the

particle bonds).

Formation of new bonds

69

THE EFFECTS OF

WATER / BINDER RATIO ON CREEP

Creep, is inversely

proportional to the

strength of concrete at

age of loading

70

FACTORS EFFECTING CREEP

The source of creep in concrete is the cement paste.

Aggregate, plays a restraint role in creep.

Water / Binder ratio.

Relative humidity.

Temperature.

Age

Stress.

71

CREEP IN CONCRETE



gel, to fill pore spaces leading to a denser matrix.

Early age creep of fly ash concrete is often higher than CEM I concrete,

reducing temp. and shrinkage induced stress (less cracks)

The “R” types cements, achieves higher early strength compared to “N”

types and would therefore allow earlier loading.

Fly Ash also contributes to the cement hydration making the concrete

denser and increasing the late strength ( post 28 day strength

development ) with long term creep similar or better than CEM I

Lower water demand for given workability, compared to CEM I cements.

72

SHRINKAGE

Concrete experience volume changes in both fresh and hardened

states.

This concerns volume changes due to moisture movement in and out of

concrete during its lifespan.

Conventional concrete generally contain more water than required for

the chemical reaction of cement to take place.

This lead to the consequence that in normal drying conditions moisture

will be lost from the concrete into the environment leading to Shrinkage.

Shrinkage and creep are closely related in that they both are moisture

dependant deformations, and the source of the moisture loss generally

is from the cement paste

73

SHRINKAGE

74

SHRINKAGE

Shrinkage is caused by loss of water by evaporation, hydration of

cement and carbonation.

The loss of water, lead to reduction in volume of the member i.e.

volumetric strain is equal to three times linear contraction.

In practice we express shrinkage as linear strain.

75

SHRINKAGE

Shrinkage in concrete is due to the cement paste.

Aggregate plays a role in modifying ways.

1. Dilution

2. Restraint

Shrinkage can be grouped in four different components.

1) Drying Shrinkage

2) Early Age Shrinkage

3) Autogenous shrinkage

4) Carbonation Shrinkage

Note: once shrinkage exceeds strain capacity of concrete cracking will

occur

76

EARLY AGE SHRINKAGE

Capillary or Plastic Shrinkage is caused in fresh concrete due to surface

moisture loss.

Plastic shrinkage is often accompanied by surface cracks.

Plastic shrinkage is the process of moisture loss to the environment by

evaporation.

77

EARLY AGE SHRINKAGE

78

DRYING SHRINKAGE

Changes in moisture content in

the cement paste, leads to

volumetric changes.

The decrease in volume due to

moisture loss, is called drying

shrinkage.

The increase in volume on

rewetting, is called swelling.

Shrinkage consist of reversible

and irreversible components

79

DRYING SHRINKAGE

80

MECHANISMS OF DRYING SHRINKAGE

Capillary tension

This occurs in the capillary pores, the

loss of moisture causes tensile

stresses in the capillary water.

Swelling pressure

Where gel particles closely approach

each other, absorbed water could

exert swelling presure, if the free film

thickness is greater than the interlayer

distance.

Surface tension

Compressive stresses occurs inside

solid particles due to surface tension.

Drying increase surface tension, with

a increase in compressive stress in

the solids

81

FACTORS INFLUENCING DRYING SHRINKAGE

The cement paste is the source of shrinkage, the porosity of concrete

will determine the rate of water transport and diffusion.

Irreversible shrinkage is normally linear to the strength of concrete and

therefore a lower water / cement ratio would lead to increase in strength

and increase in hydration.

Paste hold water, the gel pore water is more tightly held than the

capillary water.

During evaporation moisture initially lost from the capillaries, and as the

concrete matures moisture is lost from the gel pores, causing larger

sections of contraction.

82

FACTORS INFLUENCING DRYING SHRINKAGE

Paste structure

Hardened cement paste consist of solid & soft gel particles, as well as

two types of pore structures.

Very small gel pores formed by spaces between gel layers.

Larger capillary pores formed by excess water, not required for

hydration of cement

Lower water cement ratio and greater degree of hydration, will

lead to more hydration product being produced. Increasing the

ratio gel pore to capillary pore.

83

CARBONATION SHRINKAGE

Carbonation shrinkage is caused

by the reaction between carbon

dioxide from the atmosphere,

and the constituents in the

cement paste.

Shrinkage caused by

carbonation is slow, but could in

some severe cases exceed

drying shrinkage in magnitude.

84

AUTOGENOUS SHRINKAGE

Autogenous shrinkage is volume reduction as result of internal water

consumption during hydration.

Concrete with Water / Cement ratio of 0.40 and below, has a much

higher consumption of mix water, leading to higher risk of Autogenous

shrinkage.

Approximately 40% of Autogenous shrinkage occurs within the first 24h,

resulting in early age cracking.

The incorporation of fly ash has been proven to lower Autogenous

shrinkage compared to CEM I cement types (Pane & Hansen)

85

SHRINKAGE IN CONCRETE

Factors affecting shrinkage

Cement effects

There is evidence that high Alkali cement has greater risk of shrinkage

cracking, Lafarge Lichtenburg Clinker has a very low Alkali cement.

0,25% Sodium equivalent against a maximum limit of 0,6% as per ASTM

Aggregates

Aggregates has two effects on shrinkage.

Dilution : shrinkage will decrease with increase in aggregate

Restrain : shrinkage will be reduced by increase in aggregate due

to increase in stiffness.

86

SHRINKAGE IN CONCRETE




permeability of the concrete.

Fly Ash also contributes to the cement hydration making the concrete

denser and increasing the late strength ( post 28 day strength

development)

Lower water demand for given workability, compared to CEM I cements,

leading to lower moisture movement.

The good early strength achieved when using the “R” cement types,

gives better resistance to early age cracking.

87

RELATIVE SHRINKAGE POTENTIAL

Lower water demand for given workability of Powercrete Plus

42,5R and Civilcrete 32,5R, compared to CEM I cements, could

potentially reduce shrinkage by up to 75%.

88

CHEMICAL DEFORMATION OF CONCRETE

Dirk Odendaal

89

CONCRETE

Alkali Silica Reaction

Heat of Hydration

Sulphate Attacks

Chloride Attacks

90

ALKALI SILICA REACTION

What is ASR?

Reaction between Active Silica constituents of aggregate and the Alkali’s

in the cement paste and water.

Reactive forms of silica are Opal (amorphous), Chalcedony (Crypto

Crystalline), Tridymite (crystalline).

Reactive minerals are present in Opaline and Chalcedonic Cherts,

Siliceous lime tones, Rhyolitic tuffs, Dacite tuffs, Andersite tuffs and

Phyllites.

91


92


How does the reaction take place.

The reaction starts by attacks on siliceous mineral available in the

aggregate, by the alkaline hydroxides from the cement paste.

As a result Alkali Silicate gel is formed, either in the pores in the aggregate,

or on the surface of the aggregate.

This destroy the bond between aggregate and the surrounding hydrated

cement paste.

The gel (of swelling nature) consumes water, increasing in volume.

Because this gel is confined by the surrounding hydrated cement paste,

internal pressures are created.

This internal pressures will eventually lead to expansion, cracking and

disruption of the cement paste.

93


Typical appearance:

Random crack pattern.

White rim around the aggregate.

Large crack width.

Time:

May take years to develop.

Structural Effects:

Loss of strength

Loss of stiffness

Cracking

Deflection

94


Lichtenburg clinker has a low Alkali content, making Powercrete Plus

42,5R and Civilcrete 32,5R low Alkali cements

Sodium equivalent of about 0,25%, well below the 0,6% for a Low Alkali

cement (ASTM definition).

By using a low Alkali cement type, will minimize the risk of ASR

Fly Ash in Civilcrete 32,5R and Powercrete Plus 42,5R, has the ability to

react with Alkali Hydroxides in the paste, making them unavailable to

react with aggregates.

Low Alkali cement from Lafarge

Lichtenburg was used together

with fly ash and high potential

ASR aggregates (Rhyolit) for

the Mozal smelter, Bauxite silo’s

and pier in Maputo

95

HEAT OF HYDRATION

Hydration of cement compounds is an exothermic process, with Energy

of up to 500J/g can be achieved.

On the other hand, concrete has a very low thermal conductivity, and

acts as an insulator.

In mass concrete however, the heat created by hydration could lead to

significant rise in internal temp, compared to normal structures.

Rule of thumb is that the gradient between core of the concrete and the

exterior surface should not be more than 20°c.

It is therefore advisable to know the heat generating properties of the

cement to be used in this type of concrete.

For practicality, it is not necessarily only the total heat of hydration that

matters, but also the rate of heat development and the peak temperature

achieved that need to be considered.

Heat generated over longer periods, and with lower peaks can dissipate

to a greater degree.

96

HEAT OF HYDRATION

The fineness of the cement also has an impact on rate of heat

development, as the increased surface area will speed up the reaction.

Early age heat development from Hydration of cement/cementitious.

Long term caused by environmental conditions.

Effects are similar to those of drying shrinkage.

Random crack patterns.

97

HEAT OF HYDRATION

Reducing temp:

Use a Low Heat cement (LH) with an energy generation of less than 270

J/g of cement at 41Hours, as per SANS 50197-1, tested according to EN

196-9 (semiadiabatic Heat of hydration).

Powercrete Plus 42.5R = 227 J/g* at 41hours

Civilcrete 32.5R = 166 J/g* at 41 hours *Typical vales

20

30

40

50

60

70

80

Tem

p.

(oC

)

Time (days)

Typical Heat of Hydration of Concrete

OPC

OPC/30FA

OPC/40FA + 64 hours

+ 48 hours

- 12.6 oC

- 7.1 oC

98

SULPHATE ATTACKS

What is sulphate attack?

Sulphates are regular constituents in ground water, industrial waste water

and sewage water.

Different types of sulphate attacks

Calcium Sulphate attack (CaSO4)

Magnesium Sulphate attack (Mg(OH)2

Ammonium Sulphate attack (2NH3)

99

SULPHATE ATTACKS

Sulphates are common in areas where mines are operating.

These are generally calcium, sodium, potassium, and magnesium.

Sulphates, permeates the concrete (in solution with water), and reacts

with:

Portlandite in the cement paste CA(OH)2

Calcium Aluminates C3A

100

SULPHATE ATTACKS

Calcium Sulphate

When hardened cement paste is in contact with sulphates two principal

reactions takes place

• Conversion of monosulfate into ettringite

• Formation of gypsum

After the Ca(OH)2 has been consumed the sulphate solution will react with

C-S-H paste, yielding more gypsum.

This reduces the C-S ratio in the C-S-H paste reducing mechanical

strength.

Un-reacted C3A will also react with the sulphate yielding ettringite.

Ettringite is very expansive, leading to spalling of the surface, while at the

same time reducing mechanical strength by decomposition of the C-S-H

for the production of ettringite.

101

SULPHATE ATTACKS

Magnesium Sulphate

Ca(OH)2 is converted into Brucite (magnesium Hydroxide).

C-S-H paste undergoes a decalcification, reducing C-S ratio in the C-S-H

paste.

The low lime C-S-H converts to near amorphous serpentine crystals,

exhibiting no cementing properties, forming additional Gypsum.

The degration of C-S-H in the presence of Mg(SO4) is faster and more

complete than other sulphate attacks.

Eventually a double surface layer is formed, consisting of a layer of Brucite

followed by a layer of gypsum.

Magnesium sulphate attack is characterised by loss of strength and total

disintegration of the concrete under attack

102

SULPHATE ATTACKS

Ammonium sulphate attack

When hardened concrete is exposed to solution of ammonium sulphate,

the compound will decompose the highly alkaline environment of the

concrete.

Releasing gaseous ammonia.

The Ca(SO4) formed reacts with other constituent within the concrete,

producing Ettringite and causing expansion.

The overall action of ammonium sulphate is a combination of acidic and

sulphate corrosion.

103

SULPHATE ATTACKS

Attacks of Soduim sulphates Na2SO4

Gypsum has an volume increase of 20% compared to Ca(OH)2

Ettringite formation

Volume increase of 200 – 600%

104

SULPHATE ATTACKS

The formation of Gypsum and Ettringite will cause:

Expansion

Cracking

Scaling

Aggregate de-bonding from the cement paste

The severity of the Sulphate attack is dependant on the exposure,

concrete type, permeability and available water

105

SULPHATE ATTACKS

106

SULPHATE ATTACKS

Powercrete Plus 42,5R and Civilcrete 32,5R are blended Fly Ash

cements.

The incorporation of Fly Ash in the cement, decreases the amount

available alkali’s, thus preventing the formation of Ettringite.






Cement with a total Fly Ash content of more than 25%, would be

considered beneficial under Sulphate conditions .

107

SULPHATE RESISTING CEMENTS (SR)

The new revised cement specification EN197-1:2011,which is currently in the

process of being implemented, defines basically three classes of SR

cement:

Cement with no or low (< 5%) C3A (Tri-calcium Aluminate) content

Cement of type CEM III/B or C ( “Blast-furnace cements”,

meaning >65% or 90% slag content)

Cement of type CEM IV/A or B (“Pozzolanic cements”, incorporating

either siliceous fly ash or volcanic ash)

CEM IV / B-V 32,5R Civilcrete / Buildcrete is a SR cement

108

SULPHATE ATTACKS

The decrease in water absorption from 28 days to 56 days reflects an

increase in density as result of the refined pore structure

109

CHLORIDE ATTACKS

Sources of chlorides

Available on RAW materials for concrete production

External sources

Penetration through various transport systems

110

CHLORIDE ATTACKS

Effect of chloride on durability

Reinforcement corrosion

Steel embedded in concrete is protected by passivation of the steel by

the high alkaline nature of the surrounding pore water.

Carbonation encourages the neutralization of hydration products, until

the passive layer becomes unstable.

Free chloride ions dissolve in the pore water and will destroy the passive

film around the steel, causing anodic iron dissolution.

Chloride induced corrosion of reinforcement may cause the general

corrosion if the chlorides are spread over the surface of the steel.

With sufficient supply of oxygen, rapid dissolution could occur, creating

deeper pits, leading to considerable reduction in load bearing capacities.

111

CHLORIDE ATTACKS

Chloride ions reacts with cement matrix as they pass through the

concrete matrix.

A large portion of chlorides will be bound by the cement paste, physically

or chemically.

Chloride binding is beneficial to durability as that reduce the amount of

“free” chlorides in the pore water.

112

CHLORIDE ATTACKS

Types of chlorides in Concrete

Two types of chlorides must be distinguished.

Free chlorides in pore solution

Chloride ions bound to hydration products

For corrosion to occur only the free chlorides will have an impact.

Concrete containing fly ash cements is known to bind chlorides

Cement containing a relative high C3A content is desirable, due to the

chemical binding of the chloride ions to create Friedel salts.

Fly ash cements also has increased C-S-H which also binds chlorides by

absorption due to surface forces.

Whilst carbonation might release some of the bound chlorides over time,

whilst local investigations of old structures in the Cape have proven the

benefits of fly ash concretes

113

CHLORIDE ATTACKS

Transport Mechanisms:

Fluid is drawn into porous material by the capillary forces.

Amount is dependent on the saturation level of material.

Surfaces most at risk:

Surfaces where chloride concentrations are high.

Surfaces exposed to wetting and drying cycles.

114

CHLORIDE ATTACKS


Permeation

This transport mechanism becomes relevant for ingress of chlorides only if

penetrating liquids carries chlorides

During the initial period of penetration, chloride from the salt solution will

combine with the hydration products of the cement paste until an

equilibrium is achieved

The concentration of chlorides will then decrease as the depth of

penetration increase

Mostly relevant to extreme exposures, eg. marine structures

115

CHLORIDE ATTACKS


Capillary suction

Similar to permeation, the ingress due to capillary action of the pore

system absorbing chlorides containing solution

The driving force is controlled by the pore size and the effective surface

tension.

Absorption of chloride solution must be considered especially in alternating

exposure conditions.

Wetting / drying cycles are most detrimental

Depending on the relative humidity of the environment, the salts will

eventually prevent more and more moisture from evaporation increasing

the moisture concentration

With sufficient liquid paths these ions will penetrate deeper and deeper

into the concrete

116

CHLORIDE ATTACKS


Diffusion

Caused by gradient of chloride concentration

Does not depend on the flow of water to transport chloride ions

If sufficient moisture is available, it will provide a continues liquid path in

the capillary system for transportation of the chloride ions into the matrix.

The diffusion mechanism stops if there is a interruption in the liquid path

Incorporation of cements containing Pfa assist in binding these chloride

ions and limiting the depth of penetration.

117

CHLORIDE ATTACKS

Powercrete Plus 42,5R and Civilcrete 32,5R are blended Fly Ash

cements.

The incorporation of Fly Ash in Powercrete Plus and Civilcrete improve

the permeability, reducing penetration and diffusion of chlorides.

Chlorides are also chemically bound by alumino-silaceous pozzolans.






OPC OPC 30%PFA

118

CHLORIDE ATTACKS .

Maputo harbor: Chloride corrosion in front and the new bridge

containing fly ash concrete in back

119

MASONRY, MORTARS & PLASTERS

Quintin Wolmarans

120

MASONRY APPLICATIONS

Problems & common mistakes

121

Name Description Cause Solution

Grinning Positions of the

mortar joints are

clearly visible

through the plaster

Different rate of suction between the

mortar and the bricks

Apply plaster undercoat

or spatterdash coat

before plastering

Crazing Network of closely

spaced, fine

cracks

•Over trowelling a rich mix, or

•Sand that contains too many fines.

Use a better plaster sand

Cracking Larger cracks

randomly spaced

•Movement of the wall or shrinkage of

the plaster which is caused by

excessive loss of water from the plaster.

•Using a badly graded sand that lacks

fine material.

•Excessive suction by the bricks or

blocks.

•Exposure to direct sun or wind.

Do not use very rich

mixes (too much cement).

Use good quality sands.

Limit plaster thickness to

a maximum of 15mm per

coat.



122

Name Description Cause Solution

Lack of

hardness

Plaster that is easily

chipped away or is

easily scraped off after

hardening

•Plastering in full sun and wind.

•Not wetting absorbent bricks.

•Addition of extra water after first

mixing.

•Using a very lean mix (too little

cement).

Avoid causes listed

Debonding Plaster not staying on

the wall after

hardening

•Dust on the wall when

plastering.

•Over-rich mixes.

•Very thick layers of plaster (>

15mm)

Prepare surface properly

before plastering.

Limit plaster thickness to a

maximum of 15mm.

Do not use very rich mixes



123


Important Cement properties

Workability

Volume stability

Consistent cohesive mix

Open time

Good strength gain

Formulated for end use by

large building and civil projects,

requiring site custom blending

Versatile products to suite

contractors

Important Sand properties

Free of organic matter

Grading (SABS 1090 and in particular

be well graded from 5 mm particle size

downwards).

Maximum particle size

Particle shape

Clay content

124

Sand grading properties


125


126

READYMIX CONCRETE

Roelof Jacobs

127

READYMIX CONCRETE CONSITUENTS

COARSE AGGREGATE

(granite, dolomite, hornfells, quartzite, recycled..) – SANS 1083

9.5mm concrete stone





Aggregate size does not have an effect on concrete strength however good

quality aggregate may influence strength and durability.

128

READYMIX CONCRETE CONSTITUENTS

FINE AGGREGATE

Natural filler sand

Manufactured crusher sand

Sands have the biggest effect on the water demand of concrete and its

quality could also influence strength and durability..

129


CEMENTITIOUS BINDERS

Lafarge Powercrete Plus

Fly Ash

GGBS

Silica Fume

The cement / water ratio of concrete determines its strength. Cement

extenders such as Fly Ash, Slag and Silica fume may reduce / increase

water demands while improving durability by lowering heat of hydration as

well as lowering the risk of ASR, Chloride and Sulphate attack.

130


CHEMICAL ADMIXTURES

Water reducing plasticisers

Super-plasticisers

Retarders

Air-entrainers

Accelerators

Water proofing agents

These are used for reasons ranging from; reduced water content, reduced

cement contents, workability retention, retarding the hydration process,

improving freeze-thaw resistance, quick setting as well as internal

waterproofing of concrete.

131


WATER

Recycled water from internal processes

Fresh water

Fresh water yields marginally better results due to impurities present in some

recycled water sources.

132

SELF COMPACTING CONCRETE

Self Compacting Concrete

originated in Japan in the late 80’s

to combat complex structures and

high labour costs

Lafarge’s development of Agilia

began in 1995 with Lafarge South

Africa launching in Cape Town and

Durban in 2007 and Gauteng in

2008.

Definition: A concrete which flows

under its own weight, and is able to

completely fill all spaces within the

formwork, while remaining

homogeneous

Master Docs/Agilia.avi

133

134

BENEFITS OF AGILIA

Reduces placing time

Aesthetically pleasing

Improved compaction in deep level piling

Excellent compaction in areas of heavily congested rebar and difficult

access

No need for power floating or screeding

Thinner walls and columns

Quicker turnaround of shutters

No requirement for finishing crews working into late evening hours

More efficient use of labour means quicker completion of jobs

135 Peri Wiehan - Midrand

136

Le Corbusier’s Church of Saint

Pierre, posthumously completed, 40

years after his death, this structure

genuinely breathes true to his

fascination with concrete, his belief in

simplicity, functionality, building on a

human scale, and master plans that

were “in harmony with nature – sun,

space, and greenery”.

137

Spinnaker Tower, Portsmouth

by Scott Wilson Advanced

Technology Group, is the UK’s

tallest public viewing tower

outside of London. Once again

Agilia supported this innovative

design giving a perfectly

finished high quality off shutter

aesthetic.

138

ARTEVIA ADVANTAGES

Low Maintenance

Artevia Polish eliminates the need for

screeds, tiles or carpets.

Aesthetically pleasing

Monolithic slab

Colour throughout

Robust

Can be moulded into different shapes

Can be used in combination with other

products

Polished

Colour

Print

Exposed Polished

139

ARTEVIA EXPOSED EXAMPLES

139

Garden World Johannesburg Durban beach front

Riverside Office Park Oprah Winfrey Leadership

Academy for Girls

140

ARTEVIA COLOUR EXAMPLES

140

Oprah Winfrey Leadership

Academy for Girls

Goo Chi Café Durban

Private Residence CapeTown

Westville Park Durban

Durban beach front

141 141

Oprah Winfrey Leadership

Academy for Girls

Yamaha Johannesburg Private Residence Durban

Stellenbosch University Spier Wine Estate

Stellenbosch

ARTEVIA POLISHED EXAMPLES

142

EXTENSIA™

Date 1

4

EXTENSIA™ is a low-shrink design alternative to steel, mesh and fibre

reinforcement concrete.

143

Ideal for large internal industrial and warehouse

floors. Controlled shrinkage enables saw cuts to

be pushed up to 15m x 15m sections (225 m2

seamless panels) where proper design

principles are followed.

The High flexural strength of 6N–mm², allows

reduced thickness of the floor, high surface

durability and reduced floor maintenance.

Floors can be coloured and polished.

The environmental profile of EXTENSIA™ is

less than that of conventional steel-meshed

flooring.

Saves the customer money,time and effort by

reducing the need for steel reinforcement

EXTENSIA™

144

WHAT IS HYDROMEDIA?

Date 1

4

Also known as “no-fines” concrete or “pervious” concrete.

Hydromedia is a unique and effective means to address important

environmental issues and support green, sustainable growth.

By capturing storm water and allowing it to seep into the ground,

Hydromedia is instrumental in recharging groundwater and reducing

storm water runoff.

This pavement technology creates more efficient land use by reducing the

need for retention ponds, swales, and other storm water management

devices.

In doing so, Hydromedia has the ability to lower overall project costs on a

first-cost basis.

145

Manages storm water efficiently and

reduces demand on infrastructure,

rapid water removal and safe dry

surfaces.

Can reduce the quantity of first flush

runoff in urban areas.

Sustainable Urban Drainage,

minimizes urban impact on natural

water cycle.

Filters particulate including pollutants

(metals and hydrocarbons) from

storm water.

Reduced storm water management

costs and infrastructure.

Higher permeability, more consistent

performance, cleaner finish.

HYDROMEDIA: BENEFITS

146

Compressive strength of 10 – 20Mpa

Flexural strength of 1.5 – 3Mpa

Porosity 20 - 30%

Workable up to 90 minutes

Permeability rate ≥ 150 litres / m2 / min

Children's water fountain in Forever Resorts Bela Bela

HYDROMEDIA: TECHNCIAL DATA

147

1. Ultra Enviro (Low CO2 concrete)

2. Ultra Fibre (Polypropylene or Steel)

3. Ultra Waterproof (Xypex)

4. Ultra Piling NS, SD, T

5. Ultra Industrial Floor

6. Ultra Lightweight

7. Ultra Pool

8. Ultra Post Tension

9. Ultra Plaster and Mortars

148

PLACING AND FINISHING

SERVICES

Product placing and finishing

done by Lafarge

Finished product

No middle man, one point of

contact

Peace of mind for the

customer

Guaranteed product quality

and workmanship

149

QUESTIONS?

Courtesy of Patrick Rimoux (architecte)

THANK YOU

Date post:	28-Apr-2015
Category:	Documents
Upload:	sarisha-harrychund
View:	140 times
Download:	4 times

Lafarge The Production of extended cements & the impact on concrete Durability

Documents