“Green is the New Grey” - Cement Manufacturers Irelandgreen-is...A Report for Cement...

CEM II CEMENTSPortland – Limestone and Portland – Fly Ash Cements

Production, Performance and Use

A Report for Cement Manufacturers Ireland by

“Green is the New Grey”

Cement Manufacturers Ireland

22976 CMI Report V17 q7 17/10/2008 14:28 Page 1

For over 130 years the Research Institute of the German Cement Industry (VDZ) has been theleading authority in Europe on the production, performance and use of cement and concrete. VDZhas a renowned and internationally acknowledged scientific reputation for its research work notonly on process and environmental aspects of cement production but also on all aspects of theperformance of cements in high quality concrete construction.

VDZ was the founding member of ECRA, the European Cement Research Academy, which wasestablished in 2004 as a platform on which the European cement industry as a whole canstimulate, organize and follow research activities in the fields of cement production technologyand the application of cements in concrete. By creating and disseminating knowledge fromresearch, ECRA will facilitate and accelerate innovation, thus guiding the cement industry into the21st century in a sustainable manner.

Our research work is driven by the need to find sustainable and practical solutions to theenvironmental and durability requirements of designers of concrete buildings and structures in avariety of applications. The results of our work are thus capable of swift implementation.

Our multidisciplinary team addresses questions in the fields of cement and concrete productionand use and has developed state of the art solutions based on the latest scientific findings. At thesame time, our experts are available to offer a range of investigative and consultancy services inthe fields of cement and concrete technology. VDZ has been accredited and certified to ISO 9001,ISO 14001, ISO/IEC 17025, EN 45011 and EN 45012.

VDZ has had a long and fruitful relationship with the Irish cement and concrete industry and hasbeen involved over many years in advising on sustainable solutions in the area of cement andconcrete technology. Of particular note was our involvement with the Irish ConcreteSociety/Institution of Engineers of Ireland work on Alkali Silica Reaction in Concrete in the 1990s.

VDZ was particularly pleased to have been asked by Cement Manufacturers Ireland to producethis Technical Review of the Production, Performance and Use of CEM II cements. We have manyyears of practical experience of these cements, based on initial fundamental research intoperformance aspects.

We welcome the opportunity to be associated with this initiative of the cement industry in Irelandas it invests in modern methods of cement production in line with the development of sustainablebuilding solutions based on cement and concrete.

Martin SchneiderChief Executive, VDZ


Over the last decade, in all areas of human endeavour, there has been a growing interest insustainable development. As the producers of the basic raw material for concrete, which is the mostconsumed substance on earth after water, and which is essential for the sustainable development ofIreland, the members of Cement Manufacturers Ireland have, in recent years, individually andcollectively been addressing the sustainability agenda.

Portland cement manufacture is energy intensive, giving rise to carbon dioxide emissions. Theindustry in Ireland has, however, due to multi million Euro investments in BAT (Best AvailableTechnology) production facilities, now become one of the most modern and energy efficient in theworld. The carbon footprint in cement manufacture due to energy use has thus been minimised.

Carbon dioxide emissions arise in cement manufacture, not only from the use of energy, but alsofrom the decarbonation of limestone in the cement clinker production process. These processemissions are unavoidable in efficiently producing quality cement clinker from the natural limestoneraw material and to ensure that the resulting cement will have the required strength and durabilityproperties. However, by reducing the clinker content of cement the carbon footprint of cement canbe further reduced.

There has been a long and distinguished history in Europe of the production and use of cementsbased on Portland cement clinker but which incorporate other materials such as unburnt limestoneand pulverised fuel ash. These cements are now standardised at EU level in the harmonised EUStandard for Common Cements EN 197 -1 as CEM II cements.

Cements based on Portland cement (CEM I cements) have been the norm in Ireland for over acentury but now, following appropriate research and development, the Member Companies of CMIhave moved in line with European developments to the production of CEM II cements. Thesecements have been shown by research and practice to have equivalent performance characteristicsto the traditional Portland cement, well known in Ireland.

CEM II cements have now become the main cements produced and used in Ireland and in order toprovide a comprehensive data set of information for designers, specifiers and users, CMI hascommissioned VDZ, the world renowned Research Institute of the German Cement Industry, toproduce this Report on the Production, Performance and Use of CEM II cements.

I trust you will find the Report of value and commend it to all who design and build in concrete.

Jim NolanChairman



Summary

CEM I Portland cement has been the traditional cement produced and used in Ireland for manydecades. This cement has proved itself in terms of consistency, reliability and durability in a widevariety of building and civil engineering applications.

In Europe, a number of cement types have been produced and used for many decades, but thedominant cement has in the past been CEM I Portland cement. However, recently there have beensignificant developments in both cement production and use and CEM II cements now account forapproximately 60% of cement used in Europe.

Cement manufacturers in Ireland have commenced production of CEM II cements and these are nowin wide use.

CEM II cements are shown in this report to be equivalent to CEM I cements in durability terms basedon research and use across Europe. The strength performance of CEM II cements in concrete is alsodemonstrated as being similar to the traditional CEM I cements.


Contents

1 Introduction ...................................................................................................................................... 01

2 Cement ............................................................................................................................................. 01

2.1 Main constituents .......................................................................................................................... 01

2.2 Overview – types and compositions of CEM II cements..................................................................... 02

2.3 Properties of cement...................................................................................................................... 03

3 Environmental background and benefit of the application of CEM II cements .................................... 04

4 European cement market .................................................................................................................. 05

5 Concrete........................................................................................................................................... 06

5.1 Workability .................................................................................................................................... 06

5.2 Heat of hydration ........................................................................................................................... 07

5.3 Demoulding and curing .................................................................................................................. 07

5.4 Strength development.................................................................................................................... 07

5.5 Durability ...................................................................................................................................... 08

5.5.1 Porosity .............................................................................................................................. 08

5.5.2 Carbonation........................................................................................................................ 09

5.5.3 Penetration of chlorides ....................................................................................................... 11

5.5.4 Freeze-thaw resistance with and without de-icing salt............................................................. 11

5.5.5 Chemical resistance ............................................................................................................ 13

5.5.6 Resistance against alkali-silica reaction ................................................................................. 13

6 Application of Portland-fly ash and Portland-limestone cements....................................................... 14

7 Frequently Asked Questions.............................................................................................................. 15

8 References........................................................................................................................................ 16

Annex..................................................................................................................................................... 17


01

1 Introduction

The production and use of cements with several main constituents have a long and successfultradition in Europe. Today, about 70% of the cements produced and used in Europe are cementswith several main constituents. The use of other main constituents along with Portland cementclinker will depend on the ready availability and quality of these materials at an economic cost.CEM II cements, of which most sub-types utilize one additional main constituent (in addition toclinker), now account for approx. 60% of cements produced in Europe and many of these havebeen in successful use for decades.

The members of Cement Manufacturers Ireland (CMI) have now moved to the production of CEM IIcements, using Limestone or Fly ash as main ingredients along with Portland cement clinker.

This paper, commissioned by CMI, deals with the technical properties of CEM II Portland-Limestone and Portland-Fly ash cements. It also deals with the practical properties and thedurability performance of concretes made with these cements, based on investigation andresearch. The contribution of these cements to sustainable development is also outlined.

2 Cement

2.1 Main constituents

In the context of this paper, the term CEM II cement refers to Portland cement clinker combined(interground or blended) with one or more additional inorganic constituents, plus an optimisedamount of calcium sulphate (e.g. gypsum) to control setting, in accordance with the cementstandard, EN 197-1.

Clinker (K)Portland cement clinker is made by sintering a precisely specified mixture of raw materials (rawmeal, paste or slurry) containing elements, usually expressed as oxides, CaO, SiO2, AL2O3,Fe2O3 and small quantities of other materials. Limestone, shale, clay, sand, iron ore and someother mineral additives can be used as constituents of the raw material mixture.

Limestone (L, LL)Limestone meal as a main constituent of CEM II cements is made of selected and prepared high-quality limestone. The suffixes –LL and –L signify a source of high purity limestone with aparticularly low content of organic material. The limestone qualities according to EN 197-1 havealways shown excellent performance in various limestone containing cements. The limestone isgenerally interground (rather than blended) with Portland cement clinker. Specific requirements forlimestone are set out in EN 197-1.

Siliceous fly ash (V)Fly ash is obtained by electrostatic or mechanical precipitation of dust-like particles from the fluegases from furnaces fired with pulverised coal. Fly ash may be siliceous (V) or calcareous (W) innature, but in Ireland only siliceous fly ash is used. Siliceous fly ash is a fine powder of mostlyspherical particles having pozzolanic properties. Specific requirements for fly ash are set out in EN 197-1.

CEM II cements can also contain blastfurnace slag, silica fume, other pozzolanas or burnt shale,but these are not currently used in the production of CEM II cements in Ireland.


2.2 Overview – types and compositions of CEM II cements

The European standard EN 197-1 contains specification requirements for several types ofcements. Table 1 gives an overview of all common cements permitted in Europe.

Table 1: The 27 products in the family of common cements (extracted from EN 197-1)

02


In Ireland, only two sub-types of CEM II are produced and these are Portland–Limestone cementand Portland-fly ash cement (Table 2). Only CEM II/A cements are currently produced.

Table 2: Specific CEM II cements produced in Ireland

2.3 Properties of cement

The performance of CEM II/A cements corresponds widely to that of CEM I cements and theapplication range of CEM II/A cements could, to some extent, be expanded compared to CEM Icements. Manufacturers have adjusted the early strength of CEM II cements in such a way thatthe application of CEM II/A cements can be compared to the current CEM I cements (Figure 1).

In Ireland, the members of CMI have indicated that they have maintained similar strengthperformance in moving from CEM I to CEM II/A cements.

The heat of hydration development of CEM II/A cements, which is related to the initial strengthdevelopment, is approximately in the same range as that of CEM I cements.

Figure 1

Standard compressive

strength of various

German Portland

cements CEM I and

Portland-composite

cements CEM II [VDZ05]

03


3 Environmental background and benefit of the application of CEM II cements

CEM II cements have increasingly gained in importance because these permit cement plants toreduce CO2 emissions in cement production. This is primarily achieved by producing cementswith reduced clinker contents and including an increased percentage of other main constituents,such as fly ash, limestone or other permitted materials. Fly ash and limestone containing CEM IIcements, for example, have a clinker content ranging between 65% and 94% by mass, excludinggypsum. Figure 2 shows the CO2 emissions depending on the amounts of fly ash and limestone.

The use of CEM II cements therefore enhances the environmental efficiency of concreteconstruction, as the utilisation of other main constituents allows the reduction of CO2 emissionsduring cement manufacture. This presupposes, however, that these cements are largelycomparable to Portland cements in terms of their construction properties.

There are a number of possibilities for producing cements with several main constituents.Portland-composite cements offer the possibility of combining the particular advantages of theindividual components. Cements containing several main constituents are excellently suited tooptimizing the properties of concrete and mortar, such as workability, strength development ordurability. Enhanced performance of concrete using CEM II Portland-composite cements can beachieved in some applications, compared with a concrete made with CEM I. This is illustratedschematically in Figure 3 for two types of blended cements, which are compared with Portlandcement which is taken as a reference variable [VDZ07].

CO2 conditional on raw materials

CO2 conditional on thermal energy

CO2 conditional on electrical energy

Figure 2

Schematic representation of the CO2

emissions from the production of

blended cements depending on the

share of other main constituents

Figure 3

Schematic representation

of the properties of

cements and concretes

made using two cement

types with several main

constituents (blue and red

line) in comparison with

Portland cement (black line)

taken as reference cement

(100%)

04


4 European cement market

CEM I Portland cements are being increasingly replaced by CEM II Portland cements whichcontain other main constituents in addition to clinker.

A wide variety of common cements are used in the different EU member states. By way ofexample, Figure 4 shows the domestic market share of cement in 2006. The amount of CEM IIcements used was about 56%. Overall, the amount of Portland cement in the CEMBUREAUcountries in the year 2006 was 28%, whereas the amount of blended cements was 72%.

CEM II-L/LL Portland limestone cements account for the largest share of CEM II cements used,followed in second place by the sub-type CEM II-M Portland-composite cements which containmore than two main constituents (Figure 5). The use of Portland-fly ash cements is also verycommon, with approx. 16% of CEM II cements in the strength class 42.5 being CEM II-V Portland-fly ash cements. As can be seen, the amount of cements containing limestone and fly ash wasabout 56% in the strength class 42.5.

56.3

6.3 6.43.0

28.0

CEM I CEM II CEM III CEM IV CEM Vand

others

Figure 4

Market share of cements of

all strength classes in

CEMBUREAU countries in %

(2006)

Source: CEMBUREAU

9.0

15.9

39.8

30.4

4.2

0.7

S P V T L/LL M

Figure 5

Market share of CEM II-

cements of strength class

42.5 in CEMBUREAU

countries in % (2006)

Source: CEMBUREAU

05


5 Concrete

When modifying concrete composition, for example, changing the cement type, possiblemodifications to properties (e.g. workability, the effectiveness of concrete admixtures or thestrength development) can all be determined by initial testing. Also, practical experience hasdemonstrated that the effectiveness of concrete admixtures in CEM II concretes is comparable totheir effectiveness in CEM I concretes

5.1 Workability

The workability properties of a concrete are determined by concrete composition, the propertiesof the concrete constituents and the concrete temperature. The water demand of concrete ispredominantly influenced by the type, composition and quantity of the aggregate, whereas thecement type used is of minor influence.

In addition, concretes made with CEM II/A cements result in improved workability due to theoptimized particle size distribution of these cements which are therefore also suited to themanufacture of concretes of flow classes F5 and F6. In the construction of large concretestructures, produced wet-in-wet, the workability times tend to be longer for CEM II concretes andthese are often welcomed.

The water retaining capability mainly depends on concrete composition, particularly on thecontent of fine cement particles. Cements with a lower grinding fineness can give rise to atendency for water segregation (bleeding) in the fresh concrete. CEM II cements are generallyground more finely than comparable CEM I cements. This improves the water retaining capabilityand the cohesion of CEM II concretes, thus reducing the tendency for bleeding to occur.

Bridge in Merklingen, Germany. Concrete made from CEM II/A-LL 32,5 R

06


5.2 Heat of hydration

The development of heat of hydration in concrete depends, among other things, on the cementcontent and the specific hydration heat development of the cement. Generally, with the samestrength development there are no differences relevant for building practice between concreteswith CEM I and CEM II/A cements.

5.3 Demoulding and curing

The demoulding time and the time of curing of a concrete element depend, in part, on the strengthdevelopment of the concrete used and the hardening characteristics. If there are not enoughfigures based on experience, hardening or maturity tests can be carried out. Concerning theperiod of curing, concretes with CEM II cements do not require any additional curing effort. Aswith all concretes during the initial hardening phase, careful curing is necessary.

Independent of the strength development of the cement, the curing period of CEM II cementconcretes is comparable with the curing period of CEM I cement concretes.

A change from CEM I cements to CEM II/A cements has no significant effect on the fresh concretetemperature. However, the temperature of concrete constituents, as well as the climatic conditionscan have a considerable influence on the fresh concrete temperature. Therefore, as in everyconcrete application, ambient temperature and fresh concrete temperature have to be monitored -irrespective of the cement type.

5.4 Strength development

The strength of concrete made with CEM II cements is comparable to the strength development ofCEM I concretes.

Figure 6 shows the strength development of concretes with Portland-limestone cements with acomparable concrete composition and comparable storage conditions.

Figure 6

Compressive strength

of concretes made of

Portland-limestone

cements CEM II/A-LL

[VDZ]

07


Figure 7 shows, as an example, the relative compressive strength development of a concrete mixusing CEM I, CEM II and CEM III/A cements with comparable concrete compositions and storageconditions. The relative values result from the concrete compressive strength at the age of 2, 7 and28 days respectively as a factor of the 28-day concrete compressive strength.

5.5 Durability

Many European countries set out application rules for blended cements in their nationalapplication documents (NAD) to EN 206, on the basis of the successful use of blended cementsfor many years. Several European countries, therefore, allow the use of limestone and fly ashcontaining Portland-composite cements in all kinds of applications (exposure classes). The Annexshows some examples of the accepted equivalence of limestone and fly ash containing CEM II/A-cements compared to CEM I cements throughout Europe (source CEN survey of NAD’s).

Key parameters for the durability of concrete are the resistance to carbonation, resistance topenetrating chlorides, freeze-thaw-resistance with and without de-icing salt as well as resistanceagainst chemical attack. Investigations [Mül05, Mül07] and practical experience, in particular,prove the high performance of CEM II cements. Durability parameters of the concrete can bespecifically improved by using these cements.

5.5.1 Porosity

The porosity and the pore size distribution are crucial for the resistance of concrete to penetrationof detrimental gases and liquids. Measurements show, for example, that with increasing contentsof fly ash or ground blast furnace slag the amount of gel pores (< 0.01 µm) in the cement matrixincreases and the capillary porosity (> 0.1 µm) decreases [Smo76]. Therefore, the permeabilitydecreases and the concrete will become more resistant against the penetration of detrimentalsubstances. The use of Portland-limestone cements might cause a slightly higher amount ofcapillary pores in hardened cement paste which is not of importance in the practical application ofthese cements.

Figure 7

Relative

compressive

strength of

concretes made of

a range of cements

[VDZ]

08


5.5.2 Carbonation

Investigations [Sch67] on a number of reinforced concrete and prestressed concrete structuresmade of concretes of various strength classes and different compositions have shown that there isno influence of the cement type on the carbonation behaviour for concrete elements in outdoorexposure, because CO2-diffusion and therewith carbonation depth decreases significantly withincreasing moisture content (Figure 9).

Figure 8

Relative porosity of

cement mortars made

with Portland-composite

cements compared to the

porosity of Portland

cement mortar with

w/c = 0.50 at 90 days

[Mül06, Eco06]

Figure 9

Relative porosity of cement mortars made

with Portland-composite cements compared

to the porosity of Portland cement mortar

with w/c = 0.50 at 90 days [Mül06, Eco06]

09


Inside structures can show a higher degree of carbonation. However, due to the low moisturecontent of these elements there is no risk of corrosion (Figure 10).

Figure 11 shows the results from laboratory scale tests concerning the carbonation behaviour ofconcretes with different cements. It depicts that the depth of carbonation of CEM II concretes lieswithin the range of CEM I and CEM III/A concretes. (CEM III/A cements are permitted in countrieswith a long tradition in the use of blastfurnace slag (e. g. Germany, Netherlands, UK) withoutrestrictions concerning corrosion induced by carbonation.) Thus, carbonation results for CEM II/Acements lie within an acceptable range.

Depth of carbonation and risk of corrosion

Depth of carbonation

Risk of corrosion

Concrete humidity

External concrete surfaces

dry under water

Exposure XC1 XC3 XC4 XC2 XC1

Figure 10

Influence of exposure on

carbonation deph [Eco06]

Figure 11

Depths of carbonation

of concretes made

with Portland-

composite cements

and reference

cements (CEM I,

CEM III/A) as a

function of test age

and cement

composition [Mül05,

Mül07]

10


5.5.3 Penetration of chlorides

As regards resistance to penetrating chlorides, practice shows that there are differences betweenconcretes with different cements. The use of cements containing fly ash or blast furnace slag canincrease the resistance of concrete to penetrating chlorides due to a higher percentage of finepores [Bro83], i.e. the chloride migration coefficient of chloride ions decreases (cf. Figure 12).

5.5.4 Freeze-thaw-resistance with and without de-icing salt

Many years of practical experience in various European countries show that concretes with CEM IIcements containing fly ash and limestone, and with appropriate concrete composition, processingand curing, reliably comply with the standard for freeze-thaw-resistance with and without de-icingsalt.

Figure 13 shows an example of the scaling of concretes using different CEM II cements whichwere determined according to the cube test (freeze-thaw test according to EN 12390-9). Cementsthat had complied with the assessment criterion of ≤ 10 mass % scaling after 100 freeze-thawcycles have also stood the test of practice.

Freeze-thaw attack can also be simulated by the CF/CIF method. Any internal damage to themicrostructure of the concrete that occurred during this freeze-thaw attack can be determinedwith the aid of the relative dynamic elastic modulus. The relative dynamic elastic modulusmeasured at a certain test age can be compared with the original value measured on the testpiece at the start of the CF/CIF test.

Figure 12

Chloride migration coefficients of

concretes made with Portland cement

as well as limestone-, fly ash- and slag

containing CEM II cements [Mül06,

Mül07, Eco06]

Figure 13

Scaling of concretes (cube

test, c = 300 kg/m³,

w/c = 0.60) made using

various Portland-

composite cements and

well proven cements CEM I

– CEM III/A (grey shading)

as a function of the number

of freeze-thaw cycles and

of the cement composition

[Mül05, Mül07, Eco06]

11


It can be seen in Figure 14 that the concretes made with Portland-composite cements exhibitedvalues between 100 % and 80 % after 28 freeze-thaw cycles. The freeze-thaw-resistance ofconcretes based on limestone or fly ash containing cements is comparable to that of concretesbased on CEM I.

Figure 15 shows the results from freeze-thaw tests with de-icing salt with the CDF method onconcretes with different cements. For the evaluation of the results – if testing as required - acriterion for scaling of 1.5 kg/m² after 28 freeze-thaw cycles is used e. g. in Germany, this criterioncorresponds to a scaling depth of approx. 0.6 mm. The concretes made with Portland-limestonecement or Portland-fly ash cement do not show any significantly different scaling behaviour fromthat of concrete made with Portland cement.

Figure 14

Relative dynamic

elastic modulus of

concretes (CF/CIF

test, c = 320 kg/m³,

w/c = 0.50) made

using various

Portland-composite

cements as a function

of the number of

freeze-thaw cycles

and of the cement

composition [Mül05,

Mül07]

(Grey shading– value

range of concretes

made using CEM I

cements)

Figure 15

Scaling of concretes

(CDF test, c = 320 kg/m³,

w/c = 0.50, air entrained)

made using various

Portland cement and

Portland-composite

cements as a function of

the number of freeze-

thaw cycles and of the

cement composition

[Mül05, Mül07, VDZ]

12


5.5.5 Chemical resistance

The resistance of concrete to chemical attack is basically dependent on concrete compositionand particularly on the water/cement ratio. For this reason, there are no restrictions with regardto CEM II cements in some European countries. Strong sulphate attack requires cement withhigh sulphate resistance.

5.5.6 Resistance against alkali-silica-reaction

Alkalis in cements can react with reactive silica in aggregates to cause a deleterious alkali-silicareaction (ASR) in the concrete, provided moisture is present.

In Ireland, guidance on limiting the risk of ASR is given in ‘Alkali-Silica Reaction in Concrete’produced by the Institution of Engineers of Ireland and the Irish Concrete Society (2003). The alkalicontent of the cement is taken into account in calculating the alkali load in concrete, for whichlimiting values are recommended.

CEM II/A-L/LL cements will normally be lower in alkalis than CEM I cement made from the same clinker.

Bank in Ulm, Germany

Fair-faced concrete

made from CEM II/A-LL 32,5 R

13


6 Application of Portland-fly ash and Portland-limestone cements

In order to document the performance of blended cements, examples of applications of limestoneand fly ash containing cements in outstanding engineering work have been complied and arelisted in Table 3 [Eco06].

Table 3: Examples for the application of limestone and fly ash containing CEM II/A cements [Eco06]

Cou

ntry

City

/Reg

ion

Bui

ldin

g/

Con

truc

tion

Com

pone

nt

Year

of

cons

truc

tion

Cem

ent

type

Con

cret

e ba

tch/

Len

gth

DE: Stuttgart Landesgirokas

se,

Kronprinzen-

bau (Fair-faced

concrete)

Walls, Columns 1994 CEM II/A-LL 32,5 R ca. 200 m3

DE: Überlingen Prestressed

concrete

bridge, B 31

Superstructure 1998 CEM II/A-LL 32,5 R ca. 1,045 m3

DE: Waidhaus Motorway Concrete

pavement

1997 CEM II/A-LL 32,5 R Length ca. 1.2 km

DE: Merklingen Bridge All 1998 CEM II/A-LL 32,5 R ca. 210 m

DE: Regensburg Store IKEA Floor slabs,

walls, columns

2000 CEM II/A-LL 32,5 R ca. 3,000 m

DE: Bad Kötzing Lido basin, columns,

walls

2004 CEM II/A-LL 32,5 R ca. 4,000 m

DE: Ulm Bank Fair-faced

concrete

2005 CEM II/A-LL 32,5 R ca. 2,100 m

I: Piemonte

North of Italy

Motorway Asti

– Cuneo (Links

to A6 and A21)

All - CEM II/A-LL 32,5 R

CEM II/A-LL 42,5

ca. 150,000 m3

I: Pescara

Centre of

Italy

Church (Self

Compacting

Concrete)

All 2001 CEM II/A-LL 42,5

White cement

ca. 20,000 m3

I: Campania –

Calabria

South of

Italy

Motorway A3 Emergency lane - CEM II/A-LL 32,5 R

CEM II/A-LL 42,5

ca. 600,000 m3

No: Finmark Statoil “Snow White” Storage tanks

for natural gas storage terminal, Air

entrained concrete

2001 CEM II/A-V 42,5 R no information

available

No: Westcost Triangle bridge / island connecting

structure

2004 CEM II/A-V 42,5 R no information

available

14


7 Frequently Asked Questions

1. Why use CEM II cements?

In general, there are two reasons for the use of CEM II cements:

Ecological advantages – The process of burning of Portland cement clinker causes CO2emissions. By using other cement main constituents, specific CO2 emissions can be reducedconsiderably. Furthermore, fuel and raw materials resources can be conserved.

Application advantages – Due to the composition of CEM II cements, it is possible to achieveimproved performance characteristics of fresh and hardened concrete (workability,impermeability, durability).

2. What is to be considered when changing from CEM I to CEM II cements?

When changing to CEM II cements no adaptations in terms of manufacturing technology at theready-mixed concrete plant are necessary compared to CEM I cements. As in every change ofconcrete constituents, initial mix design tests should be carried out.

3. Do CEM II cement properties or constituents have an effect on the workabilitycharacteristics of concrete?

Normally, CEM II cements are ground more finely than comparable CEM I cements. This, inparticular, has a favourable effect on the cohesive properties and the water retention capacityof the concrete.

The higher fineness of grinding can lead to an increased water demand of CEM II cements instandard testing of cement. However, the water demand of the concrete is normally notaffected, because the workability characteristics of concrete are decisively determined by theconcrete composition and the characteristics of all concrete constituents.

4. What has to be observed in terms of the application of admixtures in combination withCEM II cements?

Basically, it is essential that when using admixtures in concrete, initial tests should be carriedout, in order to establish acceptable performance – this is especially so if the admixture is aPolycarboxylate ether (PCE) type. This applies similarly for concrete with Portland cement andCEM II.

Air-entraining agents are used to improve freeze-thaw resistance of concrete. In order toensure the required voids content when using cements with several main constituents, aslightly higher quantity of air-entraining agents can be necessary compared to Portlandcement. Testing is advised to establish the correct dosage level.

15


8. References

[Bak91] Bakker, R.F.M.; Roesink, G.: Zum Einfluss der Carbonatisierung und der Feuchte aufdie Korrosion der Bewehrung im Beton (Influence of carbonation and moisture on thecorrosion of the reinforcement in concrete). In: Beton-Informationen 31, No. 3/4, p.32-35, 1991.

[Bro83] Brodersen, H. A.: Transportvorgänge verschiedener Ionen im Beton (Migration ofvarious ions in concrete). Beton-Informationen 23, No. 3, p. 36-38, 1983.

[Eco06] ECOserve NETWORK. CLUSTER 2: Production and Application of Blended Cements(http://www.eco-serve.net/uploads/0032_Cluster2_argumentation_paper_final.pdf)

[Maa87] Maage, M.: “Modified Portland Cement – Summary & considerations”, SINTEF ReportSTF65 A87001, Trondheim, Norway 1987.

[Mül05] Müller, C.; Lang, E.: Durability of concrete made with Portland-limestone andPortland-composite cements CEM II/M (S-LL). Concrete Technology Reports 2004-2006, p. 29-53.

[Mül06] Müller, C.: Performance of Portland-composite cements. Cement International (4), No.2, p. 112-119 (2006).

[Mül07] Müller, C.; Severins, K.: Durability of concretes made with cements containing fly ash.Cement International (5), No. 5, p. 102-109.

[Sch67] Schröder, F.; Smolczyk, H.-G.; Grade, K.; Vinkeloe, R.; Roth, R.: Einfluß vonLuftkohlensäure und Feuchtigkeit auf die Beschaffenheit des Betons als Kor-rosionsschutz für Stahleinlagen (Influence of CO2.and moisture on the consistency ofconcrete as resistance against corrosion of steel reinforcement). DeutscherAusschuss für Stahlbeton (1967) No. 182.

[Sie07] Siebel, E., Böhm, M., Borchers, I., Müller, C.: ASR test methods – comparability andpractical relevance”, CEMENT INTERNATIONAL 1/2007.

[Smo76] Smolczyk, H.-G.; Romberg, H.: Der Einfluß der Nachbehandlung und der Lagerungauf die Nacherhärtung und Porenverteilung von Beton ; Teil: 1 ; Teil: 2 (The influenceof curing and the storage regarding the re-hardening and pore size distribution ofconcrete, Part 1, Part 2). Tonindustrie-Zeitung 100 (1976) 10, p. 349-357; 100 (1976)11, p. 381-390.

[VDZ05] Verein Deutscher Zementwerke: Mittelwerte der Druckfestigkeiten für verschiedeneZemente (Average values of compressive strength of various cements). Ergebnisseaus der Prüfdatenbank des Forschungsinstituts der Zementindustrie (unpublished).

[VDZ07] Verein Deutscher Zementwerke: Activity Report 2005-2007.

[VDZ] Verein Deutscher Zementwerke: Ergebnisse aus der Prüfdatenbank des For-schungsinstituts der Zementindustrie (Results of the data base of the ResearchInstitute of the Cement Industry, unpublished)

16


Annex

Table A1 shows examples of countries in which the cement types CEM I, CEM II/A-V, CEM II/A-Land CEM II/A-LL are approved in certain exposure classes.

Table A1: Areas of application of cements conforming to EN 197-1 in concrete conforming toEN 206-1 (examples, source CEN)

Country Exposure min f C max min c CEM I CEM IIclass 1) w/ceq (kg/m³) A-V A-L A-LL

BE C16/20 0.65 260 X X X X

CZ C20/25 0.65 260 X X X X

DE C16/20 0.75 240 X X X X

FR C20/25 0.65 260* X X X X

ITXC1

C25/30 0.60 300 X X X X

LU C20/25 0.70 240 X X X X

PT C25/30 0.65 240 X X X X

SK C20/25 0.65 260 X X X X

UK C20/25 0.70 240* X X X X

IE C25/30 0.65 280 X X X X

BE C20/25 0.60 280 X X X X

CZ C25/30 0.60 280 X X X X

DE C16/20 0.75 240 X X X X

FR C20/25 0.65 260* X X X X

ITXC2

C25/30 0.60 300 X X X X

LU C20/25 0.70 240 X X X X

PT C25/30 0.65 240 X X X X

SK C25/30 0.60 280 X X X X

UK C25/30 0.65 260* X X X X

IE C28/35 0.60 300 X X X X

BE C25/30 0.55 300 X X X X

DE C20/25 0.65 260 X X X X

FR C25/30 0.60 280* X X X X

IT C28/35 0.55 320 X X X X

LUXC3

C25/30 0.60 280 X X X X

PT C30/37 0.60 280 X X X X

CZ C30/37 0.55 280 X X X X

SK C30/37 0.55 280 X X X X

UK C32/40 0.55 300 X X X X

IE C30/37 0.55 320 X X X X

17



BE C30/37 0.50 320 X X X X

DE C25/30 0.60 280 X X X X

FR C25/30 0.60 280* X X X X

IT C32/40 0.50 340 X X X X

LUXC4

C25/30 0.60 280 X X X X

PT C30/37 0.60 280 X X X X

CZ C30/37 0.50 300 X X X X

SK C30/37 0.50 300 X X X X

UK C32/40 0.55 300 X X X X

IE C30/37 0.55 320 X X X X

BE C30/37 0.50 320 X X X X

DE C30/37 2) 0.55 300 X X X X

FR C25/30 0.60 280* X X X X

IT C28/35 0.55 320 X X X X

LUXD1

C30/37 0.55 300 X X X X

PT C40/50 0.45 360 X X X X

CZ C30/37 0.55 300 X X X X

SK C30/37 0.55 300 X X X X

UK C28/35 0.60 300 X X X X

IE C30/37 0.55 320 X X X X

BE C30/37 0.50 320 X X X X

DE C35/45 3) 0.50 320 4) X X X X

IT C32/40 0.50 340 X X X X

LU C30/37 0.55 300 X X X X

PT XD2 C40/50 0.45 360 X X X X

CZ C30/37 0.55 300 X X X X

SK C30/37 0.55 300 X X X X

UK C32/40 0.50 340 X X X X

IE C35/45 0.50 360 X X X X

BE C35/45 0.45 340 X X X X

DE C35/45 2) 0.45 5) 320 4) X X X X

IT C35/45 0.45 360 X X X X

LUXD3

C35/45 0.45 340 X X X X

PT C50/60 0.40 380 X X X X

CZ C35/45 0.45 320 X X X X

SK C35/45 0.45 320 X X X X

UK C40/50 0.40 380 X X X X

IE C40/50 0.45 400 X X X X

18



BE C30/37 0.50 320 X X X X

DE C30/372) 0.55 300 X X X X

ITXS1

C32/40 0.50 340 X X X X

PT C40/50 0.45 360 X X X X

UK C35/45 0.45 360 X X X X

IE C30/37 0.55 320 X X X X

BE C35/45 0.45 340 X X X X

DE C35/45 6) 0.50 320 4) X X X X

ITXS2

C35/45 0.45 360 X X X X

PT C40/50 0.45 360 X X X X

UK C32/40 0.50 340 X X X X

IE C35/45 0.50 360 X X X X

BE C35/45 0.45 340 X X X X

DE C35/45 7) 0.45 5) 320 4) X X X X

ITXS3

C35/45 0.45 360 X X X X

PT C50/60 0.40 380 X X X X

UK C45/55 0.35 380 X X X X

IE C40/50 0.45 400 X X X X

BE C25/30 0.55 300 X X X X

FR C25/30 0.60 280* X X X X

ITXF1

C32/40 0.50 320 X X X X

PT C30/37 0.60 280 X X X X

UK C28/35 0.60 280 X X X X

IEc C28/35 0.60 300 X X X X

BE C30/37 0.50 320 X X X X

FR C25/30 0.55 300 X X X X

ITXF2

C25/30 0.50 340 X X X X

PT C30/37 0.55 280 X X X X

UK C32/40 0.55 300 X X X X

IEc C30/37 0.55 320a X X X X

BE C30/37 0.50 320 X X X X

FR C30/37 0.55 315 X X X X

ITXF3

C25/30 0.50 340 X X X X

LU C30/37 0.50 320 X X X X

UK C25/30 0.60 280 X X X X

IEc C30/37 0.55 320a X X X X

BE C35/45 0.45 340 X X X X

ITXF4

C28/35 0.45 360 X X X X

UK C28/35 0.55 300 X X X X

IEc C40/50 0.45 400b X X X X

19


X - Permitted for this exposure classo - Not permitted* - Indicates that there are qualifications, e. g. types of main constituents

1) Exposure classes acc. to EN 206-12) With the use of AEA: One strength class lower3) With the use of AEA or slow / very slow concrete (r < 0.3): One strength class lower4) The minimum cement content of massive structures (with a smallest dimension of 0.80 m) shall

be 300 kg/m³5) Max. w/c-ratio 0.50 if a minimum content of FA (20 % by mass of (z + f) is used or if cement

CEM II/B-V, CEM III/A, CEM III/B is used for massive concrete structures with a smallestdimension of 0.80 m.

6) For air entrained concrete designed for exposure to freeze / thaw attack (XF) or slow / veryslow concrete (r < 0.3): One strength class lower

7) A strength class lower shall be used for air entrained concrete designed for exposure to freeze/ thaw attack (XF).

8) If sulfate attack applies, SR cements (CEM I-SR3 or lower, CEM III/B-SR, CEM III/C-SR) haveto be used

9) With slow / very slow concrete (r < 0.3): One strength class lower

a – f Acc. to I.S. EN 206-1:2002. Table NA.5a XF2 and XF3: If less than C40/50 use minimum air content of 5.5% (D10), 4.5% (D14), 3.5%

(D20), 3.0% (D40) where D = upper sieve size of aggregate in mmb XF4: If CEM I/GGBS combination, limit GGBS to 65% max.c See also I.S. EN 12620 and SR 16:2004 in respect of aggregatesd CEM I, CEM II/A-LL, CEM II/A-V, CEM II/A-S cementse Sulfate-resisting Portland cement or a combination of 70% GGBS and 30% CEM I. Where the

alumina content of the GGBS exceeds 14% the C3A content of the CEM I fraction shall notexceed 10%.

f If SO42- > 1400 mg/l (ground water) use footnote e above.

IE - Ireland FR - FranceDE - Germany LU - LuxemburgIT - Italy CZ - Czech RepublicBE - Belgium SK - SlovakiaPT - Portugal UK - United Kingdom


DE XA1 C25/30 0.60 280 X X X X

CZ C30/37 0.55 300 X X X X

IEC32/40 0.50 340d X X X X

C30/37 0.55 320e X X X X

DE 8) XA2 C35/45 6) 0.50 3204) X X X X

IE360d. f X X X X

320e X X X X

DE 8) XA3 C35/45 9) 0.45 320 X X X X

IE400d. f X X X X

360e X X X X

C35/45 0.50

C40/50 0.45

20


Table A2: Exposure classes acc. to EN 206-1 g)

Corrosion induced by carbonation

Where concrete containing reinforcement or other embedded metal is exposed to air andmoisture, the exposure shall be classified as follows:

XC1 Dry or permanently wet

XC2 Wet, rarely dry

XC3 Moderate humidity

XC4 Cyclic wet and dry

Corrosion induced by chlorides other than from sea water

Where concrete containing reinforcement or other embedded metal is subject to contact withwater containing chlorides, including de-icing salts, from sources other than from sea water, theexposure shall be classified as follows:

XD1 Moderate humidity

XD2 Wet, rarely dry

XD3 Cyclic wet and dry

Corrosion induced by chlorides from sea water

Where concrete containing reinforcement or other embedded metal is subject to contact withchlorides from sea water or air carrying salt originating from sea water, the exposure shallbeclassified as follows:

XS1 Exposed to airborne salt but not in direct contact with sea water

XS2 Permanently submerged

XS3 Tidal, splash and spray zones

Freeze/thaw attack

Where concrete is exposed to significant attack by freeze/thaw cycles whilst wet, the exposureshall be classified as follows:

XF1 Moderate water saturation, without de-icing agent

XF2 Moderate water saturation, with de-icing agent

XF3 High water saturation, without de-icing agent

XF4 High water saturation, with de-icing agent or sea water

Chemical attack

Where concrete is exposed to chemical attack from natural soils and ground water as given inTable h), the exposure shall be classified as given below. The classification of sea water depends onthe geographical location, therefore the classification valid in the place of use of the concrete applies.

XA1 Slightly aggressive chemical environment according to h)

XA2 Moderately aggressive chemical environment according to h)

XA3 Highly aggressive chemical environment according to h)

g) Class designation and description of the environment where exposure classes may occurgiven in the national application documents (NADs) can slightly deviate from the followingdescription.

h) Acc. to EN 206-1 / chapter 4 Classification / Table 2: Limiting values for exposure classes forchemical attack from natural soil and ground water

21


Confederation House84-86 Lower Baggot Street, Dublin 2

Tel: +353 1 605 1652Fax: +353 1 638 1652

Email: [email protected]

Irish Cement LtdPlatin. Co. Meath

Irish Cement LtdCastlemungretCo. Limerick


Lagan Cement LtdKillaskillen, Kinnegad

Co. Westmeath

Quinn Cement LtdBallyconnellCo. Cavan



Confederation House84-86 Lower Baggot Street, Dublin 2

Tel: +353 1 605 1652Fax: +353 1 638 1652

Email: [email protected]


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