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Cement and Concrete Presentation Lafarge

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    Courtesyof Patrick Rimoux(architecte)

    Production of extended cements

    & the impact on concrete

    durability

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    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

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    ABOUT LAFARGE

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    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

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    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 at1.1 billion Rand

    Internationally recognized HIV/Aids campaign in place

    First cement producer to become a member of the Green BuildingCouncil

    5

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    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

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    THE LAFARGE SPECIFIER HANDBOOK

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    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 & Earthworks2. 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 Am tsbchler,

    Pr Engineer and Manager

    Quali ty Department Southern A fr ica

    Lafarge South Afr ica

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

    and indirectly employed to satisfy todays cement market needs and to anticipate the

    future needs of our customers.

    This handbook is intended to provide a convenient guide for engineers and specifierswhen selecting quality, reliable performance cements for specific applications.

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    CEMENT MANUFACTURING

    Quintin Wolmarans

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    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.

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    Quarrying

    And

    Crushing

    Preblending

    Storage

    Raw Milling &

    Homogenisation

    Burning Cement Milling

    Packing &

    Despatch

    CEMENT MANUFACTURING

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    CEMENT CONSTITUENTS

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

    Limestone -CaCO3

    Alumina source -Al2O3 (PozzSand, Bauxite, etc)

    Iron oreFe2O3 (Magnetite)

    Silica sourceSiO2 (PozzSand)

    These materials are heated to temperatures of1450C 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)

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    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 smallparticles 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 blendof 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

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    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

    (Give cement is grey colour)

    RAW MILLING

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    Stack

    Filter

    Cooler

    CLINKER

    FuelPreparation

    Preheat TowerKiln

    To Cement mill about 100C-600C:

    free water evaporation

    800-1050C:

    CaCO3 CaO + CO2

    > 800C- 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

    > 1200C

    - formation of C3S (C2S reacts with remaining lime)

    > 1338C:

    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

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    Gypsum

    Finish Mill Cement Silos

    AdditionsLimestone, slag etc

    Fly ashClinker 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 toset 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 willmake it suitable for a wide range of applications

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    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

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    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 -

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

    Cement family:

    CEM I : Portland cement

    CEM II : composite Portland cement

    CEM III : blast furnace cementCEM IV : pozzolanic cement

    CEM V : slag and ash cement

    * See French standard for cement NF EN 197-1

    CEMENT NAMING(EXAMPLE)

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

    Cement family

    CEM I : Portland cement

    CEM II : composite Portland cement

    CEM III : blast furnace cementCEM IV : pozzolanic cement

    CEM V : slag and ash 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)

    * See French standard for cement NF EN 197-1

    CEMENT NAMING(EXAMPLE)

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

    Cement family

    CEM I : Portland cement

    CEM II : composite Portland cement

    CEM III : blast furnace cementCEM IV : puzzolanic cement

    CEM V : slag and ash 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)

    Cement with at least

    2 main constituents

    other than clinker

    * See French standard for cement NF EN 197-1

    CEMENT NAMING(EXAMPLE)

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

    Cement family

    CEM I: Portland cement

    CEM II: composite Portland cement

    CEM III: blast furnace cementCEM IV: puzzolanic cement

    CEM V: slag and ash 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)

    Cement with at least

    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 percentageof organic carbon)

    D: silica fume

    P or Q: pozzolanic materials

    T: Pre-fired shale

    * See French standard for cement NF EN 197-1

    CEMENT NAMING(EXAMPLE)

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

    Cement family

    CEM I: Portland cement

    CEM II: composite Portland cement

    CEM III: blast furnace cementCEM IV: puzzolanic cement

    CEM V: slag and ash 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)

    Cement with at least

    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 percentageof 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

    * See French standard for cement NF EN 197-1

    CEMENT NAMING(EXAMPLE)

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

    Cement family

    CEM I: Portland cement

    CEM II: composite Portland cement

    CEM III: blast furnace cementCEM IV: puzzolanic cement

    CEM V: slag and ash 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)

    Cement with at least

    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 percentageof 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

    * See French standard for cement NF EN 197-1

    CEMENT NAMING(EXAMPLE)

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    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.

    Fly ash / Pulverized fuel ash (PFA)

    Spherical particles

    0.5-300 m

    (D 50

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    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

    oreMelting agent

    =1450C

    CEMENT EXTENDERS

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    CEMENT EXTENDERS

    Fresh Concrete

    Reduces workability.

    Increases cohesiveness.

    Reduces bleeding significantly.

    Hardened Concrete

    Increased strength.

    Reduces permeability.

    Condensed Silica fume (CSF)

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    LAFARGE PRODUCT RANGE

    2

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

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    SOIL STABILISATION

    Mike Fisher

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    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

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    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

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    SOIL STABILIZATION - PRODUCTS

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

    Slower strength gain

    cementitious binder

    Higher ultimate strength

    Longer open time

    CEM IV/ B-V 32,5R

    Slower early rate of strength but

    with higher ultimate strengths

    Longer open time

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    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

    TotalProjectValue(RBillion)

    0

    20000

    40000

    60000

    80000

    100000

    120000

    140000

    160000

    180000

    CementConsumption(Tons)

    1.5 1.8% of Project Value

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    THE STOLTZ SOLUTION

    Lafarge offers contractors a unique spreading solution for roadbindercements & 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

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    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

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    MOVE FROM THIS....

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    ...TO THIS

    Consistent spread

    Dust reclaimer

    Reduce labour cost

    Silo configuration

    34t Capacity

    Independent Engine

    Digital Rate Controller

    with radar

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    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 20.4 5.6

    After Stabilisation Roadcem 2%

    4%

    6%

    24.7

    34.1

    30.6

    24.5

    29.3

    30.9

    0.2

    NP

    NP

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    LABORATORY COMPACTION DATA

    EFFORT UCS (Mpa) Average ITS (KPa) Result

    2% 10090

    3.62.1

    320.0254.0

    4% 100

    90

    6.5

    4.2

    896.0

    672.06% 100

    90

    8.3

    7.1

    706.0

    635.0

    LABORATORY WORK

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    LAFARGE ROAD PROJECTS:CURRENT AND COMPLETED

    4

    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

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    PHYSICAL DEFORMATION OF CONCRETE

    Dirk Odendaal

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    CONCRETE

    Deformation of concrete

    Elasticity

    Creep

    Shrinkage

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    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

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    DEFORMATION OF CONCRETE

    Influences on deformation:

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    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 E-moduli will vary from 5 to 25 Gpa dependant on

    w/c ratio

    Degree of hydration

    Air content

    ELASTICITY OF CONCRETE

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    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.

    ELASTICITY OF CONCRETE

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    ELASTICITY OF CONCRETE

    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.

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    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.

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    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

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    CREEP OF CONCRETE

    Creep of concrete is the increased strain under sustained constant

    stress.

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    CREEP UNDER CONSTANT STRESS

    An applied compressive stress ofapprox 40% of compressive

    strength, creep would be considered

    to be linear proportional to stress

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    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

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    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.

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    BASIC CREEP VS DRYING CREEP

    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 thecolumns.

    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.

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    BASIC CREEP VS DRYING CREEP

    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

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    THE EFFECTS OF

    WATER / BINDER RATIO ON CREEP

    Creep, is inversely

    proportional to the

    strength of concrete at

    age of loading

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    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.

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    CREEP IN CONCRETE

    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.

    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 strengthdevelopment)

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

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    SHRINKAGE

    Concrete experience volume changes in both fresh and hardenedstates.

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

    concrete during its lifespan.

    Conventional concrete generally contain more water than required forthe 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

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    SHRINKAGE

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

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    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

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    EARLY AGE SHRINKAGE

    Capillary or Plastic Shrinkage is caused in fresh concrete due to surfacemoisture loss.

    Plastic shrinkage is often accompanied by surface cracks.

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

    evaporation.

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    DRYING SHRINKAGE

    Changes in moisture content in

    the cement paste, leads to

    volumetric changes.

    The decrease in volume due tomoisture loss, is called drying

    shrinkage.

    The increase in volume on

    rewetting, is called swelling.

    Shrinkage consist of reversible

    and irreversible components

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    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 approacheach 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

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    FACTORS INFLUENCING DRYING SHRINKAGE

    The cement paste is the source of shrinkage, the porosity of concretewill 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 theconcrete matures moisture is lost from the gel pores, causing larger

    sections of contraction.

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    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.

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    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 exceeddrying shrinkage in magnitude.

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    AUTOGENOUS SHRINKAGE

    Autogenous shrinkage is volume reduction as result of internal waterconsumption 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 Pfa has been proven to lower Autogenousshrinkage compared to CEM I cement types (Pane & Hansen)

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    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.

    A sodium content of 0,25% compared to 0.6% as recommended by the

    ASTM specification.

    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.

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    SHRINKAGE IN CONCRETE

    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 also contributes to the cement hydration making the concrete

    denser and increasing the late strength ( post 28 day strengthdevelopment)

    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.

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    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%.

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    CHEMICAL DEFORMATION OF CONCRETE

    Dirk Odendaal

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    CONCRETE

    Alkali Silica Reaction

    Heat of Hydration

    Sulphate Attacks

    Chloride Attacks

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    ALKALI SILICA REACTION

    What is ASR?

    Reaction between Active Silica constituents of aggregate and the Alkalis

    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.

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    ALKALI SILICA REACTION

    S C C O

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    ALKALI SILICA REACTION

    How does the reaction take place.

    The reaction starts by attacks on siliceous mineral available in theaggregate, 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.

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    ALKALI SILICA REACTION

    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

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    ALKALI SILICA REACTION

    Lichtenburg clinker has a low Alkali content, making Powercrete Plus42,5R 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.

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    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 20c.

    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 thatmatters, 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.

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    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.

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    HEAT OF HYDRATION

    Reducing temp:

    Use a cement with an energy generation of less than 270 J/g of cement at

    41, as per EN 197-1, EN 196-9.

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

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

    Typical Heat of Hydration of Concrete

    20

    30

    40

    50

    60

    70

    80

    010 20 30 40 50 60

    Time (days)

    Temp.

    (oC)

    OPC

    OPC/30FA

    OPC/40FA

    + 64 hours

    + 48 hours

    - 12.6 oC

    - 7.1 oC

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    SULFATE ATTACKS

    What is sulfate attack?

    Sulfates are regular constituents in ground water, industrial waste water

    and sewage water.

    Different types of sulfate attacks

    Calcium sulfate attack (CaSO4)

    Magnesium Sulfate attack (Mg(OH)2

    Ammonium sulfate attack (2NH3)

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    SULFATE ATTACKS

    Sulfates are common in areas where mines are operating.

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

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

    with:

    Portlandite in the cement paste CA(OH)2

    Calcium Aluminates C3A

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    SULFATE ATTACKS

    Calcium Sulfate

    When hardened cement paste is in contact with sulfates two principalreactions takes place

    Conversion of monosulfate into ettringite

    Formation of gypsum

    After the Ca(OH)2 has been consumed the sulfate 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 sulfate 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.

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    SULFATE ATTACKS

    Magnesium Sulfate

    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 sulfate attacks.

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

    followed by a layer of gypsum.

    Magnesium sulfate attack is characterized by loss of strength and total

    disintegration of the concrete under attack

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    SULFATE ATTACKS

    Ammonium sulfate attack

    When hardened concrete is exposed to solution of ammonium sulfate, 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 sulfate is a combination of acidic and

    sulfate corrosion.

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    SULFATE ATTACKS

    Attacks of Soduim sulfates Na2SO4

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

    Ettringite formation

    Volume increase of 200 600%

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    SULFATE ATTACKS

    The formation of Gypsum and Ettringite will cause:

    Expansion

    Cracking

    Scaling

    Aggregate de-bonding from the cement paste

    The severity of the Sulfate attack is dependant on the exposure,concrete type, permeability and available water

    SULFATE ATTACKS

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    SULFATE ATTACKS

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

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

    available alkalis, thus preventing the formation of Ettringite.

    The Pozzolanic reaction produces additional Calcium Silicate hydrate

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

    permeability of the concrete.

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

    leading to lower moisture movement.

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

    considered Sulfate Resisting Cements.

    SULFATE ATTACKS

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    SULFATE ATTACKS

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

    increase in density as result of the refined pore structure

    CHLORIDE ATTACKS

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    CHLORIDE ATTACKS

    Sources of chlorides

    Available on RAW materials for concrete production

    External sources

    Penetration through various transport systems

    CHLORIDE ATTACKS

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    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 generalcorrosion 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.

    CHLORIDE ATTACKS

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    CHLORIDE ATTACKS

    Chloride ions reacts with cement matrix as they pass through theconcrete 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.

    CHLORIDE ATTACKS

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    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 Pfa 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.

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

    absorption due to surface forces.

    On carbonation of the hydration products, will cause extensivedecomposition of the Hydration products, also those that chemically

    bound the chlorides.

    Friedel salts then decompose into CaCO3 an Al2O, liberating the free

    chloride ions and the water. This leads to higher concentration of

    chloride ions close to the reinforcement.

    CHLORIDE ATTACKS

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    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.

    CHLORIDE ATTACKS

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    CHLORIDE ATTACKS

    Transport Mechanisms:

    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 anequilibrium is achieved

    The concentration of chlorides will then decrease as the depth of

    penetration increase

    Mostly relevant to extreme exposures, eg. marine structures

    CHLORIDE ATTACKS

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    CHLORIDE ATTACKS

    Transport Mechanisms:

    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

    CHLORIDE ATTACKS

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    CHLORIDE ATTACKS

    Transport Mechanisms: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.

    CHLORIDE ATTACKS

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    CHLORIDE ATTACKS

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

    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.

    The Pozzolanic reaction produces additional Calcium Silicate hydrategel, to fill pore spaces leading to a denser matrix, and reducing

    permeability of the concrete.

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

    leading to lower moisture movement.

    OPC OPC 30%PFA

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    MASONRY, MORTARS & PLASTERS

    Quintin Wolmarans

    MASONRY APPLICATIONS

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    MASONRY APPLICATIONS

    Problems & common mistakes

    MASONRY APPLICATIONS

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    Name Description Cause Solution

    Grinning Positions of themortar 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, finecracks

    Over trowelling a rich mix, or

    Sand that contains too many fines.

    Use a better plaster sand

    Cracking Larger cracksrandomly 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 orblocks.

    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.

    MASONRY APPLICATIONS

    Problems & common mistakes

    MASONRY APPLICATIONS

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    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 onthe 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

    MASONRY APPLICATIONS

    Problems & common mistakes

    MASONRY APPLICATIONS

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    MASONRY APPLICATIONS

    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

    MASONRY APPLICATIONS

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    Sand grading properties

    MASONRY APPLICATIONS

    MASONRY APPLICATIONS

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    MASONRY APPLICATIONS

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    READYMIX CONCRETE

    Herbert Groenewald

    READYMIX CONCRETE CONSITUENTS

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    READYMIX CONCRETE CONSITUENTS

    COARSE AGGREGATE

    (granite, dolomite, hornfells, quartzite, recycled..) SANS 1084

    9.5mm concrete stone

    13.2mm concrete stone

    19.0mm concrete stone

    22.0mm concrete stone

    37.0mm concrete stone

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

    quality aggregate may influence strength and durability.

    READYMIX CONCRETE CONSTITUENTS

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    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..

    READYMIX CONCRETE CONSTITUENTS

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    READYMIX CONCRETE CONSTITUENTS

    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 / increasewater demands while improving durability by lowering heat of hydration as

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

    READYMIX CONCRETE CONSTITUENTS

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    READYMIX CONCRETE CONSTITUENTS

    CHEMICAL ADMIXTURES

    Water reducing plasticisers

    Super-plasticisers

    Retarders

    Air-entrainers

    Accelerators

    Water proofing agents

    These are used for reasons ranging from; reduced water content, reducedcement contents, workability retention, retarding the hydration process,

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

    waterproofing of concrete.

    READYMIX CONCRETE CONSTITUENTS

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    READYMIX CONCRETE CONSTITUENTS

    WATER

    Recycled water from internal processes

    Fresh water

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

    recycled water sources.

    SELF COMPACTING CONCRETE

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    SELF COMPACTING CONCRETE

    Self Compacting Concreteoriginated in Japan in the late 80s

    to combat complex structures and

    high labour costs

    Lafarges development of Agilia

    began in 1995 with Lafarge SouthAfrica 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

    http://localhost/var/www/apps/conversion/tmp/scratch_7/Master%20Docs/Agilia.avi
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    BENEFITS OF AGILIA

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    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

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    116 Peri Wiehan - Midrand

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    Le Corbusiers 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.

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    Spinnaker Tower, Portsmouth

    by Scott Wilson Advanced

    Technology Group, is the UKs

    tallest public viewing tower

    outside of London. Once again

    Agilia supported this innovativedesign giving a perfectly

    finished high quality off shutter

    aesthetic.

    ARTEVIA ADVANTAGES

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    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

    ExposedPolished

    ARTEVIA EXPOSED EXAMPLES

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    Garden World Johannesburg Durban beach front

    Riverside Office Park Oprah Winfrey Leadership

    Academy for Girls

    ARTEVIA COLOUR EXAMPLES

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    Oprah Winfrey Leadership

    Academy for Girls

    Goo Chi Caf Durban

    Private Residence CapeTown

    Westville Park Durban

    Durban beach front

    ARTEVIA POLISHED EXAMPLES

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    Oprah Winfrey Leadership

    Academy for Girls

    Yamaha Johannesburg Private Residence Durban

    Stellenbosch UniversitySpier Wine Estate

    Stellenbosch

    EXTENSIA

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    123 Date 1

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

    reinforcement concrete.

    EXTENSIA

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    Ideal for large internal industrial and warehouse

    floors. Controlled shrinkage enables saw cuts tobe pushed up to 15m x 15m sections (225 m2

    seamless panels) where proper design

    principles are followed.

    The High flexural strength of 6Nmm, 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

    WHAT IS HYDROMEDIA?

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    125 Date 1

    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 reducingstorm 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.

    HYDROMEDIA: BENEFITS

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    Manages storm water efficiently andreduces 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: TECHNCIAL DATA

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    Compressive strength of 10 20Mpa

    Flexural strength of 1.5 3Mpa

    Porosity 20 - 30%

    Workable up to 90 minutes

    Permeability rate 150 litres / m

    2

    / min

    Children's water fountain in Forever Resorts Bela Bela

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    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

    PLACING AND FINISHING

    SERVICES

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    SERVICES

    Product placing and finishing

    done by Lafarge

    Finished product

    No middle man, one point ofcontact

    Peace of mind for the

    customer

    Guaranteed product quality

    and workmanship

    QUESTIONS?

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