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As evidence of the RTA’s commitment to the increased use of recycled materials, in June 1993 the RTA inconjunction with the Australasian Slag Association, released “A Guide to the Use of Slag in Roads”.VicRoads shares the same commitment to the use of recycled materials and supported the publication of thatoriginal document.
This Guide to the Use of Iron Blast Furnace Slag in Cement and Concrete produced by the Australasian SlagAssociation offers an expansion of the technical data contained in the original Guide and is supplementaryto it.
The RTA and VicRoads are pleased to co-operate with the Slag Association in the production of this Guideto facilitate the appropriate use of recycled products.
’ P
DAVID THOMSONDIRECTOR RTA TECHNOLOGYApril 1997
KERRY BURKEDIRECTOR PRODCTION SERVICESApril 1997
CONTENTS
1 . Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..*............................................~.....................................1
Types of Blast Furnace Slag. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..~............................ 1
1.1 Blast Furnace Rock Slag ....................................................................................... 11.2 Granulated Blast Furnace Slag .............................................................................. 1l.3 Ground Granulated Blast Furnace Slag................................................................. 1
2 Iron Blast Furnace Slag Concrete Aggregates 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..*........*............................
21.2 2.2 3.2 4a2 5.2 6.2 7.2 8.2 92’102’112’12.
Water Absorption .................................................................................................. 2Particle Shape ........................................................................................................ 2Wet Strength ......................................................................................................... 3Los Angeles Value ................................................................................................ 4Sodium Sulphate Soundness ................................................................................. 5Chloride Content ................................................................................................... 5Sulphate Content ................................................................................................... 5Bulk Density ......................................................................................................... 5Alkali Aggregate Reaction .................................................................................... 5Falling or Dusting Unsoundness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..*..................................... 6Iron Unsoundness .................................................................................................. 6Summary of Slag Aggregate’s Properties .............................................................. 6
3 . Slag Aggregate in Concrete . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3.1 Comparison with Natural Aggregate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7Drying Shrinkage, Flexural StrengthFigure 1. Compressive Strength . . . ..*...................................................................... 8Figure 2. Flexural Strength ................................................................................... 9Figure 3. Drying Shrinkage ................................................................................... 1 0
3.2 Cement Paste and Aggregate Interaction .............................................................. 113.3 Pumping ................................................................................................................ 1 2
3.3.1 Adequate Cement Content ........................................................................ 1 23.3.2 Adequate Ultra-Fines Content ................................................................... 1 23.3.3 Water to Cementitious Material Ratio . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 23.3.4 Slump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 23.3.5 Aggregate Proportions . . . . . . . ..~..................................................................... 1 23.3.6 Moisture Condition of the Aggregate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133.3.7 Chemical Admixtures . . . . . . ..*...................................................................*... 1 43.3.8 Some reasons for concrete not being able to be pumped t. . . . . . . . . . . . . . . . . . . . . . . . . . 1 4
3.4 Corrosion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..*.............. 1 4
A Guide to the Use of Iron Blast Furnace Slag in Cement and Concrete.
4 . Slag Blended Cement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..*........*................................15U
41.4 2.4 3.4 4.4 5.4 6.4 7.4 8.4 94’104’114’124’134’144’15.
General .................................................................................................................. 15Heat of Hydration.................................................................................................. 15Setting Time .......................................................................................................... 17Workability ........................................................................................................... 17Curing .................................................................................................................... 17Compressive Strength ........................................................................................... 18Flexural Strength ................................................................................................... 1 8Drying Shrinkage and Creep ................................................................................. 18Colour . . ..*............................................................................................................... 1 9Sorptivity . . . . . . . . . . . . . ..0.........................................................................................”..... 19Chloride Ion Resistance ........................................................................................ 1 9Sulphate Resistance ............................................................................................... 20Alkali - Aggregate Reaction.................................................................................. 20Ground Slag Blended with other Supplementary Cementitious Materials .......... .2 1Summary of Slag Cement Concrete Properties .................................................... 2 1
5 Projects which have used Slag Products . . . . . . . . ..*.................................................................. 22.
6 C o n c l u s i o n~...**............................*...........~.........*.......*.......................................................... 24.
7 Appendix A & B . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..*.............................................................*............*.....25.
8 List of References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..*..............*....................”..............*............... 28.
9 Acknowledgements e..................................*..............................*.........~...............~*......~*....... 3 1.
DISCLAIMER
The Australasian Slag Association is a non-profit Organisation which has been formed to provide aforum for exchange of information between its members and others. Since the information containedin its publications is intended for general guidance only, and in no way replaces the services ofprofessional consultants on particular projects, no legal liability for negligence or otherwise can beaccepted by the Association for the information contained in this publication. -
A Guide to the Use of Iron Blast Furnace Slag ii Cement and Concrete.
1 a INTRODUCT
Throughout the world there is an increasingfocus on the need to recycle and to more fullyutilise by-products of manufacturing processesin an attempt to conserve our finite naturalresources. Technical evaluation supported byfield experience has shown that a by-productsuch as iron blast furnace slag has, in manyapplications, properties suitable to replace orsupplement and improve traditional materials.
This booklet which is supplementary to theAssociation’s Guide to the Use of Slag inRoads, reviews in some detail the properties ofslag in cement and concrete. As there aremany types of slag, it should be particularlynoted that the term slag used throughout thisbooklet refers specifically to metallurgical slagproduced in modern iron blast furnaces, ie;iron blast furnace slag and not basic oxygensteel slag or electric arc furnace slag which aresteel furnace slags.
It cannot be over emphasised that blast furnaceslag’s potential to improve concrete quality,particularly with slag blended cements, willnot be realised unless standard good practice isobserved with the handling and placement ofthe concrete. Correct cover, compaction andcuring are all essential to ensure that theresultant hardened concrete will achieve therequired design properties such as strength anddurability. The same criteria of course applyequally to concrete containing ordinaryPortland cement.
Although the term recycling is referred towhen slag is used in any of its applications,strictly speaking slag is not a recycledmaterial. As a by-product in the manufactureof iron, blast furnace slag is a renewable virginmaterial, i.e. slag has not been previously usedbut has been formed as part of the iron makingprocess. As slag leaves the blast furnace in amolten form at 1500°C it is a homogeneousmaterial free from foreign matter.
TYPES OF BLAST FURNACE SLAGj Blast Furnace slag in Australia is produced in
three forms:
11. BLAST FURNACE ROCK SLAG
Molten slag on leaving the furnace is allowedto flow into ground bays where it air cools toform a rock like material.
1 2. GRANULATED BLAST FURNACESLAG (GBFS)
Molten slag on leaving the furnace is allowedto flow into’ a trough or granulator containinghigh pressure, high volume water sprays. Theheat energy extracted from the molten slagcauses it to change instantly into a coarse sandsized material.
1 3. GROUND GRANULATED BLASTURNACE SLAG (GGBFS)
Granulated Blast Furnace Slag when ground tocement fineness and in the presence of asuitable activator becomes a cementitiousb i n d e r .
GRANULATED BLAST FURNACE SLAG
READY FOR DELIVERY.
A Guide to the Use of Iron Blast Furnace Slag in Cement and Concrete. 1
IRON BLAST FURNACE SLAG CONCRETE AGGREGATESI
Rock slag can be crushed and screened to afull range of aggregate sizes. It is importantthat slag aggregate should not be simplysubstituted for another aggregate in an existingconcrete mix without considering differencesin particle density, grading etc. As for anyaggregate, a mix should be specificallydesigned to suit the characteristics of theaggregate. Therefore the slightly lower particledensity and higher absorption of slag should betaken into account in the mix design.
2 1. WATER ABSORPTION
As a result of its manufacturing process, slag isvesicular. This means that the individualpieces of slag aggregate contain voids whichtend to be unconnected to each other occurringthroughout the slag and appearing as blindholes on the surface.
Water absorption of slag is normally in therange of 3 to 6% by mass. Some naturalaggregates may have an absorption in the orderof 4%. The value of 2.5% set as a maximumwater absorption in some specificationsappears to be a derivation from Note 2 toclause 8.3 of AS 2578.1 (1) which reads:
“The average absorption of aggregate,other than lightweight, is about 2 per cent ‘:
However, there does not seem to be any intentin AS 2758.1 (1) to nominate a maximumvalue for water absorption for any aggregateincluding slag. Notes to Australian Standardsare for general information and are notmandatory.
The following effects should also be noted asinfluencing the measurement of the absorptionof slag aggregate, viz.:
l Greater surface area of the slag particles;
l Lower particle density of the slag.
Sometimes when drying to a saturatedsurface dry (SSD) condition, all of thewater held in the shallow surface pits ofslag aggregate is not removed by thestandard test method of surface drying.
Because of the vesicular structure of air cooledblast furnace slag, provision is made inAS 2578.1 (1) for the different waterabsorption of slag aggregate viz.,
“The water absorption of lightweight orvesicular aggregates can vary considerablywithout affecting many of the properties ofconcrete made using such aggregates “.(Note 4 to clause 8.3, AS 2758.1)
There is no doubt that the moisture content ofslag aggregates for concrete is important. Toavoid potential difficulties with the batchingand placing of concrete, slag is supplied in apre-wetted condition. It *is important that thismoisture content, around SSD condition, bemaintained whilst slag is in storage ready forbatching. Dust control water sprays fitted todelivery bins at most modern concrete plantsmay be all that is necessary to maintain thedesired moisture content.
2 2. PARTICLE SHAPE
A characteristic of slag’s structure is that itcrushes to a desirable cubical shape.
AS 2758.1 (1) specifies that the proportion ofmisshapen particles shall not exceed 10%.Quality assurance testing of 20mm slagaggregate since 1991 has shown that theproportion of misshapen particles when testedto AS 1141.14 (2) at a 3:l ratio is no morethan 3%.
2 A Guide to the Use of Iron Blast Furnace Slag in Cement and Concrete.
2 3. WET STRENGTH
In AS 2758.1 (I), one of three methods ofspecifying aggregate durability is by wetstrength and wet/dry strength variation. Therei s some question from a technologicalviewpoint as to whether the Wet/Dry StrengthVariation test is a true guide to the durabilityof slag aggregate.
The Wet/Dry Strength Variation Test wasdevised many years ago to ident:ify naturalgravels which appeared suitable for use in roadpavement construction when dry, but failed inservice under wet conditions. It wassubsequently found that some natural gravelswhich satisfied the maximum Wet/Drystrength variation, failed in service becausethey had low Wet or Dry Strength. So with theintroduction of AS 2758.1 (1) minimum WetStrength as well as a minimum Wet/DryVariation was introduced.
The tests themselves require skill and care foraccurate, repeatable results. A b r i e fdescription of the test follows. A given massof aggregate is placed in a cylinder and acompressive force applied to a plate on top ofthe aggregate. The load that would createapproximately 7.5 to 10% of fines from thesample is applied. The load is recordedtogether with the actual mass of finesproduced. The test is repeated with anotherload that would create fines from the sample inthe range 10 to 12.5%. The load and actualmass of fines is again recorded. The loadvalue representing 10% loss is interpolatedgraphically.
The test is applied to a dry sample and to asample which has been soaked in water for atleast 24 hours to become a wet sample. Fromthe two tests, the Dry Strength, the WetStrength and Wet/Dry Strength Variation aredetermined.
AS 2758.1 (1) permits values other than thoselaid down in Table 1 for Wet Strength andWet/Dry Strength Variation when vesicular
aggregate is considered. Note to Table 4 inAS 2758.1 (1) reads as follows:
“For some aggregate other (wet strength)values could be substituted in Table 4 basedo n satisfactory local experience of.materials and performance, eg. vesicularaggregate “.
In the USA it has also been recognised that atest of this type is not applicable to aggregatessuch as air cooled blast furnace slag. Hence,the American Society for Testing andMaterials, ASTM, excludes the crushing testfrom the procedures used to assess thesuitability of a material for use as an aggregatein concrete.
Whilst the test procedure is valuable inassessing riatural gravels and aggregates foruse in road pavements, it is less significantwith vesicular aggregates such as slag. Thevesicular nature of slag causes the corners andedges to readily break off when contact occursbetween single size particles in the laboratoryloading test. This type of point contact doesnot occur when the slag is set in hardenedconcrete. The apparent lack of strength of theslag aggregate does not prevent its satisfactoryuse in high strength concrete. This isillustrated by compressive strengths in excessof 100 MPa being obtained from concrete testspecimens in which ‘air cooled blast furnaceslag was used as the coarse aggregate. Referto Table 1.
A Guide fo fhe Use of Iron Blast Furnace Slag in Cement and Comrefe. 3
TABLE I- CQMPRESS VE STRENGTH OF SLAG AGGREGATE CONCRETE MIXES
Nominal Water Wet
Max Size Absorption Strength(mm) (0Oo f (kN) t
Concrete
G r a d e
Compressive Strength (MPa) for Various Mixes 0
7 days 28 days 91 days
60.5* 59.0**64.5* ‘2 59.5**53.5* 67.0-t58.0* 60.0**74.0* 73 .o+72.5* 66.5+75.0* 63 .O+72.5-t 67.5+
117.5+114.5+104.0+lOl.O+
AS 1012.9(5)
4 - 5 75 - 95 39.5 39.042.5 35.035.0 47.538.0 40.0
NOTCAST
57.0 56.057.5 52.052.0 47.054.0 48.0
NOTCAST
4 - 5 75 - 95
7 3 - 4 80 - 1001 0 4 - 5 75 - 95
102.586.086.584.0
119.0117.0107.5107.0
AS 1141.5&6 RTA-T2 15(3 (4)
Note:
1. + Values for “Water Absorption” and “Wet Strength” are from tests carried out in the NATAlaboratory of Australian Steel Mill Services in the period 199 1 - 1994.
Trial mixing and testing carried out at Pioneer Concrete NATA Laboratory (6)Trial mixing and testing carried out at Testrite NATA Laboratory (7)Trial mixing carried out at ASMS Laboratory (8)
2 . ***
3. cl The proportions for the mixes shown are detailed in Appendix A.
Angeles value which is not an accurateindication of the performance of slag concrete.
2 4. LOS ANGELES VALUE
The Los Angeles test consists of placing agiven mass of sized aggregate into a revolvingdrum containing steel balls. After a prescribednumber of revolutions the aggregate isremoved and screened. The fine materialabraded from the aggregate is weighed andexpressed as a percentage loss from theoriginal sample. The test is a very severeimpact test and usually reflects the toughnessof the aggregate particle. AS 1141.23 (9).
As for the Wet Strength Test, the Los Angelestest is not reflective of the performance of slagin concrete in the field.
Again this is due to the vesicular nature of slagwhich allows corners of the slag particle to bereadily abraded giving a misleading Los
AS 2758.1 (1) provides for values other thanthose laid down in Table 5 for naturalaggregates, with the inclusion of a category for‘Artificial Aggregates (including slags)‘, viz.Note 4 to Table 5 in AS 2758.1 (1) reads asfollows: -
“The maximum acceptable Los Angelesvalue for each source should be nominatedin the works speciJication. The value to beadopted should be based on theperformance history of the particularaggregate “,
4 A Guide to the Use of Iron Blast Furnace Slag in Cement and Concrete.
2 50 SODIUM SULPHATESOUNDNESS
Sulphate solutions such as sea water andcertain ground waters can degrade someabsorptive a g g r e g a t e b y expansivecrystallisation within the particles. Theminerals and sulphate solutions form crystals,the growth of which ultimately cause particledisintegration. Slag aggregate exhibits a highdegree of resistance to sodium sulphate attack.Quality assurance testing of blast furnace slagaggregate since 1991 has shown that sodiumsulphate loss to be less than 1% when tested toAS 1141.24 (10)
AS 2758.1 (1) specifies maximum sodiumsulphate soundness losses for particularconcrete exposures as shown in Table 2.
TABLE 2 - SODIUM SULPHATE SOUNDNESS
Concrete Exposure Maximum WeightedClassification Average Loss
PercentSevere 6
Moderate 9Protected 1 2
2 6. CHLORIDE CONTENT
After processing, slag aggregate has a chloridelevel comparable to natural aggregates.
The chloride ion content of blast furnace slagaggregate t e s t e d i n accordance withAS 1012.20 (11) generally lies in the range20-460 ppm (0.002-0.046%).
The corresponding values for natural coarseaggregates are 10 - 330 ppm (O.OOl-0.033%).
2 7l SULPHATE CONTENT
The sulphate ion content tested in accordancewith AS 1012.20 (11) generally lies in therange 680 to 1600ppm (0.068,0.160%).
The corresponding values for natural coarseaggregates are lo-1450 ppm (O.OOl-0.145%).
2 8l BULK DENSITY
Slag has the following Bul Density. (Singlesize 20mm aggregate)
Loose - 1200-1300 kg/m’. RTA Test
Compacted - 1300-1400 kg/m’. RTA TestMethod T212 (13).
These values are lower than those typicallyobtained for natural aggregate.
2 9. ALKALI AGGREGATEREACTION
Alkali-aggregate reaction in concrete resultsfrom alkalis in the cement reacting with certaintypes of silica or carbonate compoundscontained in some aggregates.
Over the past few decades the problems ofalkali aggregate reaction in concrete fromparticular natural aggregates have becomebetter known and understood. This reactioncan be very harmful as it leads to expansionand cracking of the concrete. In the case ofsome aggregates which have a slow reaction,damage to the concrete may take up to 20years to become evident. For this reason anappraisal of aggregates with this tendency isimportant for critical structures.
The Australian Standard for test ing ofaggregates for concrete, AS 1141, lists Method39 (14) as a means of recognising aggregatethat may be alkali reactive.
Regular quality assurance testing of slagaggregate to AS 1141.39 (14), since 1991 hasshown slag aggregate to be classified as“innocuous” as far as alkali aggregate activityis concerned in accordance with this standard.
An examination of the mineralogy ofAustralian blast furnace slag from PortKembla shows that slag does not containreactive forms of minerals which can causealkali aggregate reaction.
A Guide to the Use of Iron Blast Furnace Slag in Cement and Concrete. 5
2.10 FALLING OR DUSTINGUNSOUNDNESS
2.11 IRON UNSOUNDNESS
When some blast furnace slags cool from the Iron unsoundness, which o c c u r s a smolten state at about 15OOOC to around 490°C disintegration of the slag when immersed inan inversion of beta dicalcium silicate in the water, is highly likely when the slag containsslag to the gamma form may result in more than 3% ferrous oxide and at least 1% ofdisruption of the slag mass. This disruption sulphur. AS 2758.1 (1) notes that ironleads to a condition of the slag known as unsoundness has not been recorded forfalling or dusting unsoundness. Australian blast furnace slag.
AS 2758.1 (1) notes that y20 evidence has beenfound, either in Australia or overseas, ofdelayed inversion of p dicalcium silicate iniron blast furnace slag, or of deterioration ofconcrete due to the presence of p dicalciumsilicate.
Quality control testing of slag aggregate toAS 1141.37 (15) Test Method for IronUnsoundness since 1991 has found noevidence of iron unsoundness.
Chemical analysis of slags from Port Kembla,Newcastle and Whyalla show that their ferrousoxide and sulphur contents are significantlyb e l o w t h e m a x i m u m v a l u e s n o t e d i nAS 1466.74 (16). [Replaced by AS 2758.11
2.12 SUMMARY OF SLAG AGGREGATE’S PROPERTIES
I--Chloride content
PropertyProperty
Water absorptionWater absorption
Particle shapeParticle shape
Wet strengthWet strength
Los Angeles abrasion valueLos Angeles abrasion value
Sodium Sulphate soundnessSodium Sulphate soundness
Chloride content
Sulphate contentSulphate content
Alkali/aggregate reactivityAlkali/aggregate reactivity
Drying shrinkageDrying shrinkage
Flexural strength potential
Suitability for pumping (mix and pump dependent)Suitability for pumping (mix and pump dependent)
I Low I
Flexural strength potential
RatingRating
Medium to highMedium to high
CubicalCubical
+ Low+ Low
* High* High
SoundSound
Low
Low to mediumLow to medium
InnocuousInnocuous
LowLow
AdequateAdequate
AdequateAdequate
+ Refer Section 2.3* Refer Section 2.4
6 A Guide to the Use of Iron Blast Fr/mace Slag in Cement and Concrete.
3 1. COMPARISON WITH NAGGREGATE
The most detailed analysis in recent years ofslag as a concrete aggregate compared tonatural aggregate was undertaken andsubsequently reported by Gomes & Morris.This occured when designs for the SydneyHarbour Tunnel immersed tube concretesegments were being prepared.
This work was undertaken by the ConnellWagner Group Pty Ltd in partnership withFreeman Fox (Hong Kong) and was reportedin detail in a paper presented at “Concrete forthe Nineties”, Leura 1990, by Lewis Gomesand Martin Morris (17).
Despite better performance of slag aggregateconcrete as regards to drying shrinkage andflexural strength, “it was reluctantly decidednot to pursue the use of slag aggregate’: Thiswas because slag aggregate concrete wouldhave been 3% lighter than basalt aggregateconcrete and therefore a greater volume ofconcrete would be required to achieve thedesign mass.
Figures 1, 2 and 3 show test results forCompressive Strength, Flexural Strength andDrying Shrinkage reported by Haber (18). Theconclusion section of that paper is quotedbelow.
These little published results, for slagaggregate, achieved in Sydney HarbourTunnel Immersed Tube concrete testingprogram might help focus fresh attention uponthe potential benefit; beckoning the user ofslag aggregate concrete. The two mainbenefits emerging are seen as follows.
Drving- Shrinkagg
Signtficant benefits are likely to accrue fromthe use of air-cooled slag as the coarse
aggregate in the concrete. This is notaltogether surprising in view of the vesicularnature of the aggregate. For the same reason,care must be exercised in ensuring that theslag aggregate is pre-soaked in stockpiles.(Ed. Referring to Figure 3, the dryingshrinkage at the age of 91 days for the slagaggregate mixes was less than thecorresponding basalt mixes by 50 to 180microstrain for the range of bindercombinations tested)
Flexural Strength
More surprising to many is the apparentlysigntficant advantage in terms of flexuralstrength and associated tensile strain capacityaccruing from the use of slag aggregate incombination with particular binders. It hasl o n g b e e n recognised t h a t e n h a n c e dtensile/flexural strength of concrete derives
from the mortar/aggregate bond, which, in thisinstance, is again assisted by the vesicularnature of the slag aggregate. (Ed. Referring toFigure 2, the flexural strength at 28 days forthe slag aggregate mixes was higher than thecorresponding basalt mixes by 0.3 to 0.9 MPafor the range of binder combinations tested)
It is also of interest to designers that thecompressive strength of the slag aggregateconcrete doesn’t appear to suffer bycomparison with concrete containing basaltaggregate, the lower particle wet strength ofthe slag aggregate notwithstanding.
In addition to this the results of compressivestrength testing were as follows.*
For the four binder combinations tested, thecompressive strength of the concrete madeusing the slag aggregate was higher thanwhen basalt was used at all ages of test exceptfor Type “C” (now, TYPE LH LOW HEAT)cement at 28 days. In this case, thecompressive strengths were equal for the twoaggregates.
A Guide to the Use of Iron Blast Furnace Slag in Cement and Concrete. 7
FIGURE 1 - COMPRESSIVE STRENGTH
KeyII 0 Dunmore basalt
A Port Kembla slag(ED. Type “c” cement = low heat cement
ACSE = type SL, shrinkage limitedcement
Pfa = fly ash)
-
Type “C” Cement
60 -
50 -
40 -
30 -
20-
4 8 12 16 20 24 28Age in days
50% ACSE/35% Slag/l 5% pfa Cement 75% ACSE/25% pfa Cement
60
50'
40'
30
20'
10
51”““““““’ 51”““““““14 8 12 16 20 24 28 4 8 12 16 20 24 28
Age in days Age in days
50% ACSE/SO% Slag Cement
70160-
50 -
40.
30-
20-
10 -
5 D'l'l'l'l'l'l'4 8 12 16 20 24 28
Age in days
70
60
50
40
30
20
10
8 A Guide to the Use of Iron Blast Furnace Slag in Cement and Concrete.
FIGURE 2 - FLEXURAL STRENGTH
Key.. 0 Dunmore basalt
A Port Kembla slag(ED. Type “C” cement = low heat cement
A C S E = type SL, shrinkage limitedcement
P fa = fly ash)
Type “C” Cement 50% ACSE/50% Slag Cement
7
6.5
6
5.5
5
4.5
4
3.5
6.5 -
6 -
5.5 - _
5 -
4.5 -
4 -
3.5 -
3 ” I I I I I I 3 ” I I I I I I
5 15 25 5 15 25
Age in days Age in days
50% ACSE/35% Slag/l 5% pfa Cement 75% ACSE/25% pfa Cement
6.5
6
5.5
5
4.5
4
3.5
6.5
6
5.5
5i
elf 4.55
22 4LL 1
5 15 253
5 15 25
Age in days Age in days
A Guide to the Use of Iron Blast Furnace Slag in Cement and Concrete. 9
FIGURE 3 - DRYING SHRINKAGE
Key.. 0 Dunmore basalt
A Port Kembla slag(ED. Type “C” cement = low heat cement
A C S E = type SL, shrinkage limitedcement
Pfa = fly ash)
n
600
500
400
300
200
100
Type “C” Cement 50% ACSE/50% Slag Cement
0’~““““”10 30 50 70 90
Age in days
50% ACSE/35% Slag/l 5% pfa Cement 75% ACSE125% pfa Cement
600 600
z mo!!50 400
0 I
.
.
I
s
k”-:--
g 500!!!5P 400
.- 2 300tk.2c 200.-L6 100
010 30 50 70 90 10 30 50 70 90
Age in days Age in days
600 I
010 30 50 70 90
Age in days
1 0 A Guide to the Use of Iron Blast Furnace Slag in Cement and Concrete.
One fascinating feature to emerge j?om theSydney Harbour Tunnel investigation notpreviously published is the benejt to begained in terms of reduced heat of hydrationfrom the use of s lag aggregate incombination with a slag/y ash blendedcement. Figure 4 depicts the adiabatictemperature proJile obtained porn the use ofsuch a cement blend in combination with slagaggregate compared with Dunmore basaltaggregate. (Ed. Commonly referred to asIllawarra basalt)
FIGURE 4 -TEMPERATURE RISE IN CONCRETEEFFECT OF AGGREGATE TYPE
3 5 % S l a g / l 5 % F l y A s h / S O % A C S E
4 0
0;&g 30 -.__.._.___.___...__.- *_ ._........_.._..______._____n
i?izQ) 20 -________________-_ _______.-_.___._____.-.----------L
4 0 6 0
T i m e i n H o u r si)- Basalt * Slag
8 0 1 0 0
3.2 CEMENT PASTE ANDAGGREGATE INTERACTION
Vaysburd (19) reported that lightweightaggregate in concrete developed a contact zonebetween the cement paste matrix and thelightweight aggregate particles which wasdifferent to the zone that formed between thecement matrix and dense aggregate.
0 T h e z o n e a r o u n d t h e l i g h t w e i g h taggregate was shown to be low inporosity and free from micro-cracks andporous pockets.
0 The zone around the dense aggregate wasweak and porous due to water beingtrapped at the underside of the aggregateparticle and insufficient packing of thecement paste around the aggregate.
Vaysburd (19) illustrated the crack free andlow porosity zone around 1aggregate by a scanning electron microscope.This clearly showed uninterrupted adherenceof the cementitious matrix to the aggregateparticle in structural grade concrete.
Zhang and Gjorv (20) i l lustrated thepenetration of cement paste into the pores oflightweight aggregate using backscatteredelectron images.
While air-cooled slag is not a true lightweightaggregate, its relatively higher absorption andsurface characteristics tend to make the contactzone around the slag particles less porous thanfor dense aggregate.
Presence of a porous and micro-crackedtransition zone between a natural aggregate,Indiana limestone, and the cement paste andcement mortar matrix has been illustrated byAquino et al (21) using scanning electronmicroscopes. A water to cement ratio of 0.35was used in all mixes for this study.
In work commissioned by James (22) it wasshown that in concrete containing Port Kemblablast furnace slag, the vesicles in the surface ofthe slag particles are filled by the cementitiousmortar resulting in a dense zone of materialimmediately surrounding the slag particle.This was clearly illustrated in a micrograph ofa section taken through the concrete (normalstructural grade strength).
The test data in Table 1 demonstrate that thehigher water absorption of slag aggregate isnot a sign of weakness of the aggregate.
A Guide to the Use of Iron Blast Furnace Sag in Cement and Concrete. 11
3 30 PUMPING
Concrete made with vesicular coarseaggregate, such as slag aggregate, can besuccessfully pumped. However as with anyother aggregate, attention to detail is requiredto ensure trouble-free pumping and some basicinformation is listed below.
As for any other aggregate, the mix design forslag aggregate must satisfy certainrequirements viz.:
3.3.1 Adequate Cement Content
Concrete with a cement content below 280kg/m3 will generally prove difficult to pumpbecause of lack of lubrication. Howevercement contents in excess of 450 kg/m3 canproduce stickiness and reduce pumpability.
3.3.2 Adequate Ultra-Fines Content
An adequate amount of ultra-fine materialshould be incorporated in the mix, i.e. materialfiner than 150 microns. This is generallycontributed from part of the cement, flyash,ground granulated blast furnace slag, sand, andall of the silica fume. The total weight ofcement and ultra-fines should be between 300and 450 kg/m” for concrete containing 20mmmaximum size aggregate.
3.3.3 Water to Cementitious MaterialRatio
This ratio should lie generally between 0.4 and0.65 to provide a pumpable mix.
3.3.4 Slump
The slump of the concrete should be within therange 80 to 1OOmm. Slumps in excess of1OOmm can be pumped as long as steps aretaken to prevent segregation of the mixingredients. Any concrete below 80mm slumpmay be more difficult to pump than higherslump concrete.
3.3.5 Aggregate Proportions
The coarse and fine aggregate generally shouldbe proportioned to produce a continuousgrading although gap graded concrete can bepumped as long as the gap is not toopronounced. For small diameter lines, 75 andlOOmm, the grading envelope presented byEgan (23) in Figure 5 may be used as a guidefor proportioning the aggregates for a 20mmnominal mix.
FIGURE 5 - COMBINED AGGREGATE GRADING ENVELOPEFOR PUMPING CONCRETE THROUGH 75 AND IOOmm
DIAMETER LINES .
150 300 600 1.18 2.36 4.75 9.5 19Pm m m
Sieve Size
hap graded concrete may be pumped providedthe gap does not extend over more than twosieve sizes as shown on a typical graph inFigure 6.
Absence of material between consecutivesieves requires an increase in material bothfiner and coarser than the omitted fraction.(Refs. 24 and 25). The actual amount ofadjustment of the finer and coarser materialwill depend on the gradings of the aggregateused.
1 2 A Guide to the Use of Iron Blast Furnace Slag in Cement and Concrete.
FIGURE 6 - RECOMMENDED COMBINED GRADING ENVELOPEFOR PUMPING CONCRETE (16mm Aggregate - Schwing)
100 I
E“B” LINE \
0) C4@.
“A” I IMe \ 74/.;2 80
zMaI
$? 60 I IE
I
0I I I I / 1
0.25 0.50 1 . 0 2 . 0 4 . 0 8 . 0 1 6 . 0Mesh Size in mm
Mesh screens(DIN 4188, sheet 1) +t+
Square mesh screens(DIN 4187, sheet 2)
Schwingrecommendsgracfingdesign between linesA& B
Figure 6 illustrates the gap in the gradingcurve between the 2.0 and 8.0mm mesh sizes.This has been taken from the Germanpublication “Pumping Concrete and ConcretePumps” from Schwing (24) which uses thestandard German sizes for s ieves andaggregates.
It should be noted that the graphs in Figures 5and 6 apply to any aggregate and not just slag.
Concrete, in which the aggregate grading has agap or lack of particles of more than one sizewithin the grading, is more likely to bemoisture sensitive and segregate at highslumps and may have poor workability. Hencewhen considering the workability of concrete,the overall grading of the combined coarse andfine aggregate, and not just the coarseaggregate, must be taken into account. In fact,it is thought that the grading of the fineaggregate is more important for workabilityand reduced bleeding than that of the coarseaggregate.
Mixes made using slag aggregate may requirea slightly higher sand content to providepumpability. Australian experience has shownthat this increase is of the order of 2%.
Another approach to proportioning the coarseand fine aggregate in a concrete mix designedfor pumping is to use an optimum volume ofcoarse aggregate per cubic metre of concrete.
For a slag with a known particle density, thiscan be translated into a particular mass ofcoarse aggregate per cubic metre of concrete.
As a guide, for a slag with a particle density ofthe order of 254Okg/cubic metre, the quantitiesof coarse slag aggregate shown in Table 3provide a base line for proportioning thecoarse and fine aggregate.
TABLE 3 - QUANTITY OF COARSE SLAGAGGREGATE PER CUBIC METRE OF
CONCRETE FOR PUMPABLE CONCRETE
MAXIMUM SIZEOF COARSE
AGGREGATE(mm)
20
1 0
Mass of Coarse Aggregate(Sa tu ra t ed su r face d rycondition) kilograms percubic metre of concrete. Avalue towards the lower endof the range should be usedwhere pumping factors areexpected to be lessfavourable due to conditionssuch as low cement and/orultra-fines content of theconcrete.
900 - 1050
650 - 850
Difficulties encountered in pumping concretecontaining 20mm slag aggregate in conditionsadverse to pumping, ie through lines of lessthan 1OOmm diameter, with abrupt reducers orexcessive lengths of rubber hose, can beeliminated by replacing 25 to 50% of the slagaggregate in the mix with an equal volume ofwell graded, good shaped 20mm naturalaggregate.
3.3.6 Moisture Condition of the Aggregate
To enable concrete containing slag aggregateto be pumped, the slag must be at or near theSaturated Surface Dry condition at the time ofbatching.
A Guide to the Use of Iron Blast Furnace Slag in Cement and Concrete. 13
3.3.7 Chemical Admixtures
Chemical admixtures that are suitable for usein concrete containing aggregate other thanslag are normally suitable for use with slagaggregate concrete.
3.3.8 Some reasons for concrete(irrespective of aggregate type) notbeing able to be pumped include -
a) too little water;
b) too much water;
c) poor shape of the aggregate;
d) oversize pieces of aggregate;
e) inadequate pre-wetting of porous orvesicular aggregates;
f) use of inappropriate admixtures orincorrect dosage;
g) foreign objects in the concrete;
h) inadequate priming of the pump andpump line;
i ) poor condition of the pump or line;
j) pump line configuration too severe;
k) inadequate line diameter and thenumber of bends, reductions, etc.;
1) hardening or bin the pump or
eeding of the concreteine;
3 4. CORROSION
Slag aggregate does not have any adverseeffect on reinforcing steel in concrete. As withnatural aggregates the concrete should be ofadequate quality and well compacted withsufficient cover given to the reinforcing steel.
Slag aggregate is alkaline in the presence ofmoisture, having a pH in the range of 10.5 to11.5. The presence of slag aggregate inconcrete does not reduce the alkalinity ofconcrete and therefore does not increase thelikelihood of corrosion of steel reinforcement.
An extract from a previous Austral ianStandard 1466 - 1974 Metallurgical FurnaceSlag Aggregate (16) reads as follows:
“The suggestion has often been made thatiron blast furnace slag aggregate inconcrete may contribute to corrosion ofsteel reinforcement. It has, however beenfound from numerous tests and extensivepractical experience that the use of suchslag complying with existing standards doesnot introduce any cause of corrosion notpresent with other aggregates. Providedthat the same precautions are taken toobtain a properly consolidated concreteand adequate cover to the reinforcement asare necessary with dense naturalaggregates, there is no additional risk ofcorrosion. If
Research carried out by the CSIRO (26) showsthat use of slag cement is not likely to increasethe corrosion rate of steel reinforcementcompared to ordinary Portland cement.
CORE SAMPLE FROM 6OMPA SLAG CEMENT& SLAG AGGREGATE CONCRETE.
1 4 A Guide to the Use of Iron Blast Furnace Slag in Cement and Concrete.
4 l SLAG CEMENTI
410 GENERAL
Slag cements currently available in Australiacontain 20-40% slag for general constructionand 60-70% slag for applications whichrequire reduced heat of hydration, increasedresistance to the ingress of chloride ions,improved sulphate resistance and to inhibitalkali-aggregate reaction. Cement with a highproportion of slag is particularly useful forconcrete in a marine environment.
Slag cements of other binder proportions maybe produced by cement manufacturers ifrequired in commercial quantities.
AS 3582.2 (27) sets out the requirements forground granulated blast furnace slag as asupplementary cementitious mater ial incement and mortar.
Ground granulated blast furnace slag (GGBFS)may perform differently with various brandsand types of Portland cement with which it isblended or interground. In some cases thismay lead to better strength development andshorter setting times. For special applicationstrial mixes are recommended to determine theoptimum slag blend.
When specifying slag cement, the particularrequirements of the concrete and theconditions to which the concrete will beexposed should be advised. Table 4 givessome indicators of desirable slag contents.
Note:
For the purposeestablished term(OPC) has beerPurpose Cementthe terminology 1
of this document, the longOrdinary Portland Cement
1 used rather than General(GP). This is consistent withdsed in an earlier guide to the
v
use of slag in roads.
TABLE 4 - RECOMMENDED SLAG CONTENT INCEMENT FOR VARIOUS APPLICATIONS OF
CONCRETE
Slag Proportion AsPercentage Of TotalSlag And PortlandCement Content
(Note 3)
Application
General construction 20 - 40
Where it is desirable toreduce heat of hydration(Note 1)
50 - 80
Structures exposed tochloride attack (Note 2)
50 - 80
Structures exposed tosulphate attack (Note 2)
50 - 80
Marine structures 60 - 80
Where the cement andaggregate to be used inthe concrete has thepotential for alkali-aggregate reaction
50 - 70
Note 1: Depends on degree of reduction required.Portland cement content is also important.
Note 2: Degree of severity of expected exposure alsorequires consideration.
Note 3: Higher slag contents may be consideredsubject to trial mixes.
4.2 HEAT OF HYDRATION ANDTEMPERATURE RISE
The use of slag cement will reduce the rate ofheat generation in concrete and the extent oftemperature rise. The actual level of reductionwill depend on the nature and relative quantityof cement and slag being used. In concrete,factors such as cement content, fineness of theslag, ambient temperature, the size and shapeof the element will influence the rate andextent of temperature rise. Typical heat ofhydration and changes in temperature forcement blends tested in a Langavantcalorimeter are shown in Figures 7 and 8.
A Guide to the Use of Iron Blast Furnace Slag in Cement and Concrete. 15
FIGURE 7 -ADIABATIC HEAT OF HYDRATION
3 5 0
a 3 0 0EE2
2 5 0
s 2 0 0a3 1500- 100
5 0
- - _ _ - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
L - _ _ _ _ _ _ - _ - - - - - - - - - - _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
L _ _ _ _ _ _ _ - _ _ - - - _ - - - - - - - - - - - - - - -_ - - - - _ _ _ _ _ _ - _ _ _ _ _ _ _ _ _ _
- _ _ _ _ _ _ _ - - _ - - - - - - - - - - - - - - -_ _ _ _ _ _ - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
- - _ _ _ _ _ _ _ _ - - - - - - - - - - __ _ _ _ _ - _ _ _ _ - _ _ - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
L _ _ _ _ - - _ - - - - - _ - - - -_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ - - _ _ - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
- _ - - _ - - - - - - - - _ - - - _ _ _ _ _ - _ - - - - - - - _ _ - _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Time (hrs)
Note: Langavant Method
FIGURE 8 - TEMPERATURE DIFFERENCE DEGREES (ADIABATIC)
OPUSLAG
4 70/30+- 50/50+ 35165- GP
35.00
30.00
25.00
8z 20.00a.Ea, 15.00t-
10.00
5.00
I
r---------------------------- --------J/-a. --------- -- -----------------------------.
L-_--_--_----------_---- $ -_-_ If------ ---- ---\-- ------ --- ------------ - _----- -------__
r - - - - _ - - _ - - - - _ - - _ - - - - - - - - - - - -
ii%
- - - - - - -_ - - - _ _ - - - - - - _ - - - - _ - - - - - ~ - - - ~ ~ .
r - - - - _ - - _ - _ - - - - - - - - _ - - - - - - - - - - - _ - - - - _ - - - - - - - - - - - - - - - - - - - - - - - - - -
M /
- - - _ _ _ - _ _ - - - - - - _ - - _ _ _
.4
L - - - - - _ _ _ - - - - _ _ _ _ _ _ _ - _ _ _ _ _ _ _ _ - - _ - - _ _ - - _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ - - - - _ _ _ - - - - _ _ .
L _ _ _ _ _ _ _ - _ _ - _ _ _ _ _ _ - _ - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I
Time (hrs)
Note: Langavant Method
OPClSLAG
4 70/30+ 50150+ 35/65- GP
16 A Guide to the Use of Iron Blast Furnace Slag in Cement and Concrete.
4 3. SETTING TIME 4 4. WORKABILITY
Under normal conditions an increase inconcrete setting time can be expected whenslag cement is used. The level of setretardation is dependent on the initial curingtemperature of the concrete, the water tocement ratio, the OPC content and thepercentage of slag in the cement. Thecharacteristics of the OPC and any admixtureused are also important. If setting time iscritical, trial mixes are recommended toestablish what increase in setting time willoccur.
In summer time and other times when theambient temperature would normally cause theconcrete to set more quickly and so reduce theavailable finishing time, this increase in settingtime can be advantageous.
Setting time tests were carried out with fourdifferent brands of Australian OPC. Thesecements were tested both before and afterblending with slag in the proportions of 70%OPC, 30% slag both with and without threelocally available similar type chemicaladmixtures.
The range of initial set results for thesecements is shown in Table 5. As can be seensome slag cements will set more rapidly thansome Portland cements both with and withoutadmixtures.
TABLE 5 - INITIAL SET OF VARIOUSCEMENTS AND ADMIXTURE
COMBINATIONS*
Cement
OrdinaryrPortland Cement(OW
II Slag Cement(70% OPC, 30%
II slag)
WithoutAdmixture
4.80 to 6.00hours
5.50 to 7.25hours
WithAdmixture
5.25 to 6.75hours
6.08 to 9.16hours
* Initial set tested in accordance with AS 1012.18 (28)
Workability is generally improved in concretescontaining slag cement compared to concreteswith OPC. There are a number of theories toexplain the phenomenon. It appears theimproved workability is due to the increasedpaste volume and higher fluidity of the pasteand mortar.
The improved workability of concretescontaining slag cement is reflected in waterdemand which is reduced compared to OPCc o n c r e t e o f similar slump. Thewater/cementitious ratio can be reduced toobtain the same slump for an OPC concrete.When the water to cement ratio is consideredto be particularly critical, it may be necessaryto carry out a trial mix to determine the effectof the use of the slag cement on this ratio. Areduced water demand usually results ingreater density and strength.
4 50 CUBING
Curing is extremely important for allconcrete to develop its potential strengthand durability. When a sufficiently moistatmosphere is not maintained at theconcrete surfaces in the initial stages ofhardening and strength development, earlydrying will occur and the potentialproperties of the concrete will not beachieved.
From the time of placement all concreteshould be protected, from the excessiveevaporation d u e t o h i g h w i n d s , h i g htemperature and low relative humidity.Once concrete has sufficiently hardened, allof its exposed surfaces should be protectedfrom drying out by using an appropriateprocedure eg. ponding with water, coveringwith polythene sheeting, wet hessian, orspraying completely with an effective curingcompound.
A Guide to the Use of Iron Blast Furnace Slag in Cement and Concretes 1 7
Concrete made with slag cement hydratesmore slowly than OPC concrete which can bequite beneficial. However, slag cementconcrete does require greater attention tocuring.
In the absence of any requirements ofparticular specifications, such as RTA BSO(29), the data shown in Table 6 is a guide torecommended wet curing times for slagcement concrete.
TABLE 6
Number of Wet Curing Days
Average 20 - 40% 40 - 55% 55 - 70%
Ambient Slag Slag Slag
Daily Temp
Above 20°C 5 7 7
5 - 12Oc 9 12 12
Placing of any concrete at low temperatures(below 5OC) will interfere with the hydrationprocess, resulting in delayed development ofstrength, and if below 0°C possible frostdamage. It is advisable to maintain theconcrete temperature above 10°C by providinginsulation or supplying heat to the concrete.
When it is proposed to use elevatedtemperature curing for products such as pre-cast or pre-stressed concrete units, it isimportant to establish the most suitable curingcycle for that concrete mix irrespective ofwhether it contains slag or not.
4 6a COMPRESSIVE STRENGTH
Concrete containing slag cement generallydevelops strength more slowly than concretemade from OPC. [Hinczak (30), Butler &Ashby (3 l)]. However, slag cement concretecontinues to gain strength at a higher rate atlater ages than OPC concrete. Slag cementsare capable of being used to produce concretewith high strengths at 28 days and later ages.
taining higher slag contents,above, is normally specified
for purposes other than strength eg. heat ofhydration. Strengths are sometimes specifiedin these cases at ages later than 28 days.Strength at 56 days is frequently nominated.
4.7 FLEXURAL STRENGTH
The design requirements for flexural strengthcan be readily achieved using slag blendedcement.
Hinczak (30) reported that at ages beyond 7days concrete made using slag cementgenerally gave higher modulus of rupturevalues than concrete containing only OPC atthe same binder level.
Flexural strength in excess of 4 MPa at 3 daysand 6.5 MPa at 28 days for concretecontaining 50/50 slag cement was reported byHaber (18) Figure 2.
4 8. DRYING SHRINKAGE ANDCREEP
The drying shrinkage of concrete is affected bymany factors such as the nature and amount ofcement paste and the type and quantity ofaggregate.
It has been indicated that the long term dryingshrinkage of concrete containing ground slagis similar to OPC concrete but may be higherat early ages. (Hinczak, 30)
Work at the Western Australian Institute ofTechnology indicates that for concrete with acementitious content of 420 kg/m”, dryingshrinkages for 100% OPC concrete and 65%slag 35% OPC concrete were similar for up to3 weeks drying but from 3 to 12 weeks dryingthe 100% OPC concrete shrank at anincreasingly greater rate than the 65% slag35% OPC concrete (32).
18 A Guide to the Use of Iron Blast Furnace Slag in Cement and Concrete.
Drying shrinkage testing of the 50 and 60grade mixes of Table 1 made using slagcement with 65% slag content illustrates thelow shrinkage of this cement type withshrinkage values for these mixes after 56 daysdrying all below 350 microstrain (6).
The inclusion of ground slag in concrete canreduce its creep compared to concretecontaining only OPC as the binder. This effectis enhanced as the slag content is increased.
4 9. COLOUR
Depending on the fineness and the chemicalcomposition of the slag, the colour of exposedconcrete surfaces containing slag blendedcement is usually lighter than concretecontaining only OPC as the binder. The colouris influenced to a large extent by the colour ofthe OPC used.
In some instances a bluish tinge appears in theconcrete when slag cement is used. This iscaused by the presence of trace quantities ofcalcium sulphides. These oxidise rapidly andthe bluish tinge dissipates when the concrete isexposed to the atmosphere. The phenomenonis normal and does not affect the quality of theconcrete.
4.10 SORPTIVITY
Sorptivity, or the rate of ingress of water intoconcrete, has received a lot of attention byresearchers in recent years. This interest hasarisen because of the increased awareness ofthe need to improve the durabil i ty ofreinforced concrete structures.
Work reported by Ho (33) showed that theresponse of concrete to the rate of waterabsorption and to interrupted curing can beimproved by the incorporation of ground slag.The rate of water absorption in concrete bycapillary action was significantly reducedwhen 35 percent ground slag was used and awater reducing admixture was incorporated.At the lower range of strengths, the sorptivity
of concrete containing slag cement was not asadversely affected by interrupted curing asconcrete with OPC as the binder.
Tests for water sorptivity were conducted indeveloping a concrete specification for theEsso offshore concrete gravity oil drillingplatform (34). The results are shown inTable 7.
TABLE 7 - WATER SORPTIVITY
CementitiousBinder
Test Results(mm/min”)
OPC + GGBFS + SF
1 OPC + GGBFS
This test measures the uptake of water into theconcrete
OPC = Ordinary Portland Cement orGeneral Purpose cement.
SF -- Silica fumeGGBFS = Ground granulated blast furnace
slag.
The results are all below the value of 0.12mm/min”.s which is an acceptable value forgood quality concrete. The triple blend mix isa slightly better performer although all mixesexhibit minimal capillary uptake of water.
4.11 CHLORIDE ION RESISTANCE
The resistance to the penetration of chloridesinto concrete is dependent mainly on the porestructure of the cement paste and the nature ofthe products of the binder/water reactions.
For blends of ground slag and OPC, theresistance to chloride penetration increaseswith increasing slag proportion. Concretemade using cement containing 60% or more of
A Guide to the Use of Iron Blast Furnace Slag in Cement and Concrete. 19
slag is considered to be highly impermeable tochloride ions (35). Refer to Figure 9.
FIGURE 9 - RESISTANCE TO CHLORIDE IONPENETRATION
(BINDER CONTENT 300Kg/m3)
0 10 20 30 40 50 60 70 80 90 100
% Slag Blend
ASTM CIZOZ-91, “Standard Test Method for Nectrical Indication ofConcrete’s Abilitv to Resist Chloride Ion Penetration”.
In this test, the higher the charge passed, thelower the resistance to chloride ionpenetration.
4.12 SULPHATE RESISTANCE
Concrete can be exposed to attack fromsulphates from various sources includingground waters, industrial effluent and its by-products, decay of organic matter, sewage, andsea water.
Slag cements improve the resistance ofconcrete to sulphate attack by reducing thepermeability of the cement paste matrix andreacting with the calcium hydroxide in thehardened cement paste thus reducing theavailability of one of the compounds that arehighly susceptible to sulphate attack (37).
Work by CSIRO, using a test methoddeveloped by the Cement and ConcreteAssociation of Australia (36), has shown thatslag cement containing 40 .to 80% slag hashigher sulphate resistance than OPC and somesulphate resisting cements complying withAS 3972 (38).
Frearson concludes in his paper ‘SulfateResistance of Combinations of PortlandCement and Ground Granulated Blast FurnaceSlag’ (39) ‘IEVen at the lowest (30%)replacement levels tested, the OPC - Slagmortars were more resistant to sulfate attackthan OPC alone although they were generallyless resistant than SRPC mortars” (SulphateResistant Portland Cement).
The use of cement with higher slag contentsshowed greater resistance to sulphate attackthan the lower slag contents (40). Figure 10illustrates the improved sulphate resistanceprovided by slag cements.
FIGURE 10 - EXPANSION OF MORTAR BARS EXPOSEDTO SULPHATE SOLUTION
0.4 1 i i j : j ; ; jI i I
0 . 3 5
0.3
8 0.25
00 2 4 6 8 1 0 12 14 1 6 18
Period of Exposure (weeks)
+ T y p e S R ( B r a n d A ) -0- Type SR (Brand B)
-M- OPC/BF Slag 65135 --++ OPC/BF Slag 35465
Test Method, Australian Standard AS 2350.14 (37)
4.13 ALKALI-AGGREGATEREACTION (ALKALI-SILICAREACTION)
The alkali-aggregate reaction refers to thereactions that can occur between the alkali ofcement and certain siliceous compounds foundin some aggregates.
These reactions can cause expansion andcracking in concrete.
It has been shown that slag cement is effectivein reducing the expansion of aggregates thathave been found to be alkali-silica reactive.
20 A Guide to the Use of Iron Blast Furnace Slag in Cement and Concrete.
,s obtained using varying proportions of“X irom 10 to 50% of the total cementitious
der indicated that of the proportions used,ld minimum percentage of slag to obtain less
xpansion than the 100% OPC mixture was20% (41). With high cement content mixes itwas concluded that it was necessary to replacemore than 40% of the cement by slag toprevent damage from occurring due to alkalisilica reaction (4 1)
4.14 GROUND SLAG BLENDED WITHOTHER SUPPLEMENTARY
i CEMENTITIOUS MATERIALS
The use of fly ash and or silica fume togetherwith ground granulated slag and OPC provideblended cements which have been in commonuse in particular applications for many years.
The use of ground slag and fly ash togetherwith OPC was pioneered in Australia by Visek(42). Further reports were made on usingground slag and fly ash in OPC concrete byHeaton (43), Brantz (44) and Hinczak (45).
Malhotra (46) reported on concrete mixesmade using OPC together with the threematerials, ground slag, fly ash and silica fumeall in the same mixes. All of these concretemixes gave 28 day compressive strengths inexcess of 85 MPa.
’ The use of combinations of these threesupplementary cementitious materials withOPC in concrete, is technically and practicallyvalid. It has been shown that these materials‘.re very compatible and complementary when;ed together in concrete.
nbinations of these materials are therefore1 as ways to achieve improved performance
ncrete such as enhanced durability andth. The combination to be used will’ on the design requirements of the
ar project and the economics and. .I tY of each supplementary
PUS material.
4.15 SUMMARY OF SLAG CEMENTCONCRETE PROPERTIES
Property Rating
Heat of hydration Low
Setting time Extended IIWorkability
Curing time
Improved
Increased
Compressive strength
Flexural strength
Adequate
Adequate
Drying shrinkage
Creep
Sorptivity
Chloride ion resistivity
Normal
Reduced
Reduced
Improved
Sulphate resistance I Improved II
Alkalli/aggregatereactivity
Improved
GRANULATED SLAG B E I N G PRODUCED AT
NO.5 BLAST FURNACE. BHP PT. KEMBLA.
Te of Iron Blast Furnace Slag in Cement and Concrete.
r5 0 PROJECTS WHICH HAVE USED SLAG PRODUCTS
1. Sydney Harbour Tunnel
The cement for the immersed tubesegments comprised 40% ACSE(Shrinkage limited) cement with 60% BFgranulated slag interground withoptimised gypsum content. Approx.36,000 tonnes of cement were used forthese units.
2. Glebe Island Bridge - Sydney
The two pile caps supporting the towersfor this cable stayed bridge utilised highslag cement as used in the SydneyHarbour Tunnel. Each of the capscontained approx 2,800m3 of concretewhich was continuously poured.
3. No. 6 Blast Furnace - Port Kembla
The foundation block for this 100 metretal l furnace, comprising 2300m3 ofconcrete used a tertiary cementcomprising four parts high slag (60-65%)cement with one part of fly ash to limit theheat of hydration. BF slag aggregate wasalso used in the concrete. I A further13 ,000m3 of slag cement/slag aggregatewas used for associated works.
4. Esso - West Tuna-Bream B Oil Platforms
These concrete gravity structures (CGS)were constructed at the Port Kemblacasting basin before towing to theirlocations in Bass Strait. The caissons orthe fully submerged sections of theplatforms utilised two different mixes, viz.
The base concrete comprised high slag(60%) cement with 20mm aggregate. Thecaisson walls used a quaternary blend of87% high slag (60%) cement with 11% flyash and 2% sil ica fume and 1Ommaggregate.
The upper sections of the CGS’s includingthe roof and shafts which incorporate thesplash zone, were cast with a blend of50% OPC with 35% slag, 10% fly ash and5% silica fume and 14mm aggregate.
5. Sandringham Marina - Port Phillip Bay,Melbourne
A tertiary cement was used comprising55% ordinary Portland cement with 35%slag and 8 to 10% silica fume.
6. Maribyrnong River Bridge
This bridge has a total length of 520m(54m spans) and was constructed using anincremental launch system. The*construction method allowed segments tobe placed at one end and subsequentlylaunched (jacked) into position on aweekly cycle.
Slag cement 70% OPC, 30% slag.20,OOOm’ of concrete.
7. Calder Freeway Upgrade (Bridges)
60% OPC, 40% slag.
8. New Crown Casino Piles
Aggressive ground water conditionsadjacent to the Yarra Piver required pilesto have a high durability. 30,OOOm’ ofconcrete using high slag and fly ash wasused.
9. New Melbourne Exhibition Centre
This 84m x 360m post tensioned flooru s e d 30-50% s l a g c e m e n t t o g i v e30,OOOm* of pillarless uninterrupted .space.(Largest open area exhibition space in theSouthern Hemisphere).
22 A Guide to the Use of Iron Blast Furnace Slag in Cement and Concrete.
1 0 .
11 .
1 2 .
13.
tPost tensioned floor system for MajorWarehouse / Distribution Centre for theMurray Goulburn Company.
Slag cement 70% OPC, 30% slag.17,OOOm’ of floor space.
Ballarat Road Bridge. Melbourne-
35% slag, 65% OPC. 5,OOOm’ of concrete.
3 5 % s l a g , 6 5 % O P C . 16,OOOm’ o fconcrete.
Womens Prison - Deer Park, Victoria
35% slag, 65% OPC. 4,000m3 of concrete.
14. Textile Factory, Melbourne35% slag, 65% OPC. 15,000m3 ofconcrete paving.
15. Offshore Oil Storage Platform, Wandoo.Western Australia.65% slag cement. Structure weight8 1,000 tonnes.
16. Concrete Stack, BHP Port Kembla140m tall stack used slag aggregate35 & 40Mpa concrete.
SLAG AGGREGATE CONCRETE STACK
140M TALL. PORT KEMBLA.
FOUNDATION BLOCK NO 6 BLAST FURNACE PT KEMBLA. SLAG CEMENT & SLAG AGGREGATE.
A Guide to the Use of Iron Blast Furnace Slag in Cement and Concrete. 23
60
Today more than ever before , environmentalawareness and recycling are receivingincreased attention. The slag productsdescribed in this publication are all suitable forthe purposes outlined, and as such arecompetent construction materials suitable foruse in their own right and not just as analternative to dumping.
The use of slag in cement represents asubstantial reduction in the generation ofgreenhouse gases. A reduction of one half atonne of CO, discharged into the atmosphere is
achieved for every tonne of slag substituted forOPC in the production of blended cement.The use of rock slags conserves the energyalready expended in their production and alsoconserves our finite natural resources.
This Guide, together with supplementarybooklets, is intended to provide an overview ofavailable research data together withreferences to enable Engineers to evaluate thecost-effectiveness of slag as an important civilengineering and constuction material.
24 A Guide to the Use of Iron Blast Furnace Slag in Cement and Concrete.
APPENDICES
APPENDIX A
Refers to Table 1 on Page 5
1 . Mix Proportions (SSD) kg/cu.mConcrete Grade 50
MaterialMix Designation
Slag cement 1
Slag cement 2
Ultra fine fly ash
Silica fume
20mm slag
1Omm slag
Medium river sand
Slag crusher fines
Dune sand
Water reducer
A.E.A.
Superplasticiser
Water (litres)
c 5
450
-
640
280
-
440
410
J
J
170
C6 c 9 Cl4 Cl5 Cl8 c20 c22
450 400 420 - 410 440 400
420 - - -
- 40
20
650 620 675 675 690 660 670
280 270 295 295 300 290 290
790 - 820 820 830 826 811
- 550 - - I - -
- 330 - - - - -
J J J J J J J
J
J J J J J J J
160 160 150 160 140 144.5 155
Slag cement 1 - Portland cement brand 1 with high proportion of slag
Slag cement 2 - Portland cement brand 2 with high proportion of slag
A Guide to the Use of Iron Blast Furnace Slag in Cement and Concrete. 25
Appendix A (Continued)
2 . Mix Proportions (SSD) kg/cu.mConcrete Grade 60
I Slag Cement .j I I II Slag Cement 4 I I I
*&GE cement
i
10025 1 0680 1 640
Fly ashSilica fume20mm slag1Omm slag
Medium river sandSlag crusher finesDune sand
25710310
-280500
30 30 30 40670 675 660 660300 300 295 295
760 770 750 750
4
300 1 280 300 (7604
Water reducer I J
A.E.A. IBuperplasticiser 1 J 1 J I J I J 1 J I J I J 1 J1 Water (litres)-
150 160 1601 160 ) 160 1 174 1 150 ) 150 1
Slag cement 3 - Portland cement brand 3 with high proportion of slag.Slag cement 4 - Portland cement brand 4 with lower proportion of slag.
3 0 High Strength MixesMix Proportions (SSD) kg/cu.m
Material Mix Designation
I 1 I 2 I 3 I 4Ordinary Portland cement I 543 I I 543 ISlag Cement(65% OPC 35% Slag)
570 572
Silica fume I 97 I 68 I 97 I 681Omm slag I 719 I 717 I 711 I 7117mm slag-6mm slag . I I I 342 I 342Medium river sand I 793 I 790 I 472 I 472SuperplasticiserWater (litres) I 116.5 I 115.6 I 123.6 I 123.6
26 A Guide to the Use of Iron Blast Furnace Slag in Cement and Concrete.
APPENDIX
Refers to Section 3.1 including Figures 1,2 & 3
“Two sets of four mixes were produced, each set being identical except for the use of natural(Dunmore basalt) or slag aggregate,. However it was necessary to use a slightly increasedwater/cement ratio for the natural aggregate mixes’!
Mix Components (Stage 1 Test)
I Binder I RatioOh I
TYPe c 1 0 0
I ACSE/GGBFS I 50150 I1 ACSE/GGBFS/PFA 1 50/35/s 5 I
ACSEIPFA I 75125 I
MARIBYRONG RIVER BRIDE - MELBOURNE - SLAG CEMENT
CONCRETE ARTERIAL ROAD. KEILOR PARK - MELBOURNE - SLAG CEMENT
bide to tt?e Use of Iron Blast Furnace Slag in Cement and Concrete. 27
1 .
2 .
3 .
4 .
5 .
6 .
7 .
8.
9,
10.
II.
12.
13.
AS 2758.1 -Aggregates and rock for engineeringpurposes - Part 1 - Concrete aggregates, StandardsAssociation of Australia, 1985.
AS 114 1.14 - Methods of sampling and testingaggregates - particle shape by proportional calliper,Standards Association of Australia, 1974.
AS 114 1.5 & 6 - Methods of sampling and testingaggregates - Bulk density and water absorption offine & coarse aggregate, Standards Association ofAustralia, 1974.
RTA T2 15 - NSW Roads and Traffic AuthorityTest Method “Washington Degradation Test”.
AS 10 12.9 - Methods of testing concrete: Methodfor the determination of the compressive strengthof concrete specimens, Standards Association ofAustralia, 1986.
Pioneer Concrete Laboratory Report Numbers5602815603 1, 56029/56032, 56030/56033,56014156025, 56015156026, 56016156027.
Testrite Laboratorv Report Numbers C9 176,C9177, C9185, C9233.
ASMS Internal Memo dated 21/4/94, 1915194.
AS I 14 1.23 - Methods of sampling and testingaggregates - Los Angeles Value, StandardsAssociation of Australia, I980.
AS 114 1.24 - Methods of sampling and testingaggregates: Soundness (by use of sodium’sulphate), Standards Association of Australia,1974.
Australian Standard AS 1012-20: Methods oftesting concrete. Determination of chloride andsulfate in hardened concrete and concreteaggregates - Standards Australia, I992.
RTA T211 - NSW Roads and Traffic AuthorityTest Method “Loose Unit Mass of Aggregate”.
RTA T2 12 - NSW Roads and Traffic AuthorityTes t Method “Compac ted Uni t Mass o fAggregate”.
14.
15.
16.
17.
18.
19.
20.
21.
22.
2 3 .
24.
AS 1141.39 - Methods of sampling and testingaggregates - Potential Reactivity of Aggregates(Chemical Method), Standards Association ofAustralia, 1974.
AS 1141.37 - Methods for sampling and testingaggregates - iron unsoundness.
AS 1466 - Australian Standard for MetallurgicalFurnace Slag Aggregate, Standards Association ofAustralia, 1974. (Withdrawn)
Gomes L. & Morris M.W., 1990 - “The Design andPerformance of a Slag/Cement Concrete for theSydney Harbour Tunnel Immersed Tube Units”.Cements for the Nineties, Leura NSW.
Haber E, 1994 - “Physical Characteristics ofConcrete Containing Port Kembla Iron BlastFurnace Slag Aggregates” - Concrete in Australia;Vol. 20, No. 2, June 1994, pp 14-16. ConcreteInstitute of Australia, North Sydney, Australia.
Vaysburd A.M. - “Durability of lightweightconcrete and its connections with the compositionof concrete, design and construction methods”,American Concrete Institute SP 136-7. 1992Detroit USA.
Zhang, M.H. and Gjorv, 0.E. “Penetration ofcement paste into lightweight aggregate”, Cementand Concrete Research, Vol. 22., pp 47-55, 1992Pergamon Press, USA.
Aquino, M.J . , Zongjin, L. and Shah, S.P. ,“Mechanical Properties of the aggregate andcement interface”. Advanced Cement BasedMaterials, 1995, 2, pp 211-223, Elsevier ScienceInc NY, USA.
James, W., Examination using a high poweredmicroscope of the interface between blast furnaceslag aggregate and the cementitious mortar, ASMSInternal Report, 1993.
Egan D.E. - “Concrete Pumping for Multi-StoreyBuildings” - Construction Review, May 1,985, ppl-8.
Eckardstein K.E. Van - “Pumping Concrete andConcrete Pumps - A concrete placing manual”(Schwing) Germany, 1983.
28 A Guide to the Use of Iron Blast Furnace Slag in Cement and Concrete.
25.
26.
27.
28.
29.
30.
31.
32.
33.
34.
Putzmeister Ltd - “Concrete for Pumping”.Derbyshire S419QB, United Kingdom (BP 192-1UK) .
Cao H.T., MacPhee D . E . , B u c e a L . a n dSirivnatnanon V. - “Corrosion Characteristics ofSteel in Blast Furnace Slag - Portland CementBlends” - 9th International Congress on thechemistry of cement, New Delhi, India 1992.
AS 3582.2 - Supplementary CementitiousMaterials for use with Portland Cement. Slag-ground Granulated Iron Blast Furnace, StandardsAustralia, 199 1.
AS 1012.18 - Methods of Testing Concrete -Method for Determination of Setting Time of FreshConcrete, Mortar and Grout by PenetrationResistance (metric units). Standards Association ofAustralia, 1975.
NSW Roads and Traf f ic Author i ty - QASpecification B80, Concrete Work for Bridges,Edition 3, 1994.
Hinczak 1. - “Properties of Slag Concretes - anAustralian Experience” International workshop onthe use of fly ash, slag, silica fume and othersiliceous materials in concrete. Concrete ‘88Workshop - Sydney, Australia July 4-6, 1988 pp199-229.
Butler B. & Ashby 9. - “A further report on theinfluence of curing environment upon theproperties of concrete made using a variety ofPortland cement supplements” - Transactions ofInstitution of Engineers, Australia, CivilEngineering, Paper C/609 pp 45-55, 1986.
Anderson L., Report on testing of slag cementconcrete for Swan Cement, CSR ReadymixConcrete and BHP Engineering; WesternAustralian Institute of Technology, Perth, WesternAustralia, 1982.
Ho D.W. S., Hinczak I., Conroy J. J. and LewisR.K. - “Influence of slag cement on the watersorbtivity of concrete” Second InternationalConference on use of Fly Ash, Silica Fume, Slagand Natural Pozzolans in Concrete, Vol. 2, Madrid,Spain, 1986.
Taywood Engineering report, 19 November 1994,“Shaft Mixes for Esso Project, Section 2.4.1 WaterSorptivity”.
35.
36.
37.
38.
39.
40.
41.
42.
43.
44.
Baweja D., Sirivnatnanon V. & Koerstz P.- “RapidChloride Ion Permeability of Concrete Samples” -CSIRO Report BIW 0492, November 92.
Mak S.L., Ho D.W.S., Ritchie D. CSIRO document92/63(m) - “Sulphate Resistance of PortlandCement Slag Binders”, May 1992.
AS 2350.14 - Methods of Testing Portland andBlended Cements Length Change of Portland andBlended Cement Mortars Exposed to a SulfateSolution, Standards Association of Australia, 1996.
AS 3972 - Portland and Blended Cements -Standards Australia, 199 1.
Frearson J.P.H. - “Sulfate Resistance ofCombinations of Portland Cement and GroundGranulated Blast Furnace Slag” - Proceedings,Second International Conference on use of FlyAsh, Silica Fume, Slag and Natural Pozzolans inConcrete, Vol. 2, Madrid, Spain, 1986.
Mak S.L., Ho D.W.S. & Ritchie D. “SulphateResistance of Portland Cement Binders” - CSIROdocument DBCE Dot. 92/63(M) May 1992.
Higgins D.D. and Conneil M.D. - “Effectiveness ofgranulated blast furnace slag in preventing alkalisilica reaction” - Proceedings of 5th InternationalConference on Fly Ash, Silica Fume, Slag andNatural Pozzolans in Concrete, Milwaukee,Wisconsin USA, June 1995.
Visek J.C. - “The Development and Use of BlastFurnace Pozzolan and Fly Ash together withOrdinary Portland Cement as CementitiousMaterial in Concrete”, Internal report, SpecifiedConcrete Pty Limited, Wollongong, NS WAustralia, 1969, p 17.
Heaton B.S. - “Characteristics of Concrete withPartial Cement Replacement by Fly Ash andGround Granulated Slag: Symposium on Concrete,Cases and Concepts” Institution of Engineers,Australia, Canberra, 1979.
Brantz H.L. and Beal D.L. “Development ofSuitable Mixes for Portland Cement ConcreteContaining both Fly Ash and Granulated BlastFurnace Slag”, Concrete for the Nineties, Leura,Australia., Concrete Institute of Australia andCSIRO Division of Building, Construction andEngineering, 1990.
%de to the Use of Iron Blast Furnace Slag in Cement and Concrete. 29
45. Hinczak 1. and Roper H. - “Ternary Cements”,Concrete for the Nineties, Leura, Australia, ConcreteInstitute of Australia and CSIRO Division ofBuilding, Construction and Engineering, 1990.
46.
47.
48.
49.
50.
51.
52.
Malhotra V.M. - “Ternary Cementitious Systemsfor Producing High-Strength Concrete”, Concretefor the Nineties, Leura, Australia, Internationalconference on the use of fly ash, slag, silica fume,and other siliceous materials in concrete, 1990.
Andrews-Phaedonos F., 1993 - “Use o fSupplementary Cementitious Materials inConcrete, Ground Granulated Blast Furnace Slag,Fly Ash, Silica Fume”.
Haber E, 1994 - “Slag Blended Cements inConcrete”, Melbourne.
Hinczak 1, 1993 - “Granulated Iron Blast FurnaceSlag as a Cementitious Constituent in Concrete”
Anderson J .R. & Wel l ings P .W. , 1 9 9 1“Construction of the Foundations for the Towers ofthe New Cable-Stayed Glebe Island Bridge”,Concrete Institute of Australia Conference, May1991.
Bakker R.F.M., 1991 - “Use & Performance ofBlast Furnace Cement Concrete”, SupplementaryCementitious Materials in Concrete Seminars,C&CA, September 199 1.
Baweja D. Munn R.L., Roper H. & SirivnatnanonV., 1992 - “In Situ Assessments of Long TermPerformance o f P l a i n & Blended CementStructures”, Institution of Engineers, AustralianCivil Engineering Transactions, June 1992.
53.
54.
55.
56.
57.
. Morrehead D.R. & Boyd R.E., 1991 -“Shielding Concrete for the National MedicalCyclotron”, Department of Nuclear Medicine,Royal Prince Edward Hospital, Sydney. CIAConcrete ‘9 1, Sydney 199 1.
Hinczak I., 1991 - CIA Current Practice Note No.26. Ground Granulated Iron Blast Furnace Slag &Its Use in Concrete.
Munn R.L. Baweja D., Roper H. & Sirivnatnanonv., 1991 - “Field Performance of Pavement andWharf Structures having Blast Furnace Slag andFly Ash Blended Cements”, Concrete Institute ofAustralia’9 1.
Sirivnatnanon V. Cao H.T. & Baweja D., 1991“Durability Performance of Blast Furnace SlagBlend Concrete Structures, CSIRO, AustralasianSlag Association Seminar, Port Kembla, July 199 1.
Snowden R., 1992 - “The Specification & Use ofSlag in South Africa”, SupplementaryCementitious Materials in Concrete Seminars,C&CA, September 1992.
SYDNEY HARBOUR TUNNEL SUBMERGED TUBE SECTION - SLAG CEMENT
30 A Guide to the Use of Iron Blast Furnace Slag in Cement and Concrete.
ACKNOWLEDGEMENTS
The Guide is the product of extensive cooperation between the NSW Roads and Traffic Authority,Vicroads and the Australasian Slag Association to better understand and develop the utilisation ofindustrial slag products.
The invaluable contribution to this Guide of the experience and expertise of the following isgratefully acknowledged:
Len Anderson ConsultantFred Andrew+Phaedonos VicroadsJohn Ashby Australian Steel Mill ServicesRobert Barber Ability Building ChemicalsBarry Butler CemConSult InternationalVal Brizga Roads & Traffic Authority of NSWDavid Dash Roads & Traffic Authority of NSWGordon Dobson Steel Cement LtdAlan Dow Steel Cement LtdChris Francis Roads & Traffic Authority of NSWEd Haber Taywood EngineeringBrian Heaton University of Newcastlelhor Hinczak Blue Circle Southern CementWayne James Australian Steel Mill ServicesDavid Jones BHP Flat Products DivisionAndrew Kemeny Heggies Bulkhaul
Lance Midgley V i c r o a d s .’John Pattison Pioneer ConcreteDoug Prosser Australasian Slag AssociationPaul Ratcliff Australian Steel Mill ServicesAndrew Robertson Cockbum CementMartin Venour BHP Long Products DivisionMike Veysey Roads & Traffic Authority of NSWTom Wauer Steel Cement LtdGeoff Youdale Consultant
Particular recognition is made’to the efforts of the Editorial Committee comprising John Ashby,Wayne James and Doug Prosser.
‘3 the Use of Iron Blast Furnace Slag in Cement and Concrete. 31
NOTES
32 A Guide to the Use of Iron Blast Furnace Slag in Cement and Concrete.