C t ASTM S ifi tiCurrent ASTM Specifications

ASTM Committees C01 and C09ASTM Committees C01 and C09Workshop on Specifications on

Alkali Aggregate ReactionAlkali-Aggregate Reaction

St. Louis, MOJune 6, 2010

Alkali- AggregateAlkali AggregateReactions ( AAR )

• Alkali-silica reaction (ASR) ( )• Alkali-carbonate reaction (ACR )

Alkali-Silica Reactivity

RequirementsRequirements

• Reactive silica• Sufficient alkaliSufficient alkali• Available moisture

Standards

• Provide clear criteria for definingProvide clear criteria for defining materials, design and construction practices test methodspractices, test methods

• Provide unambiguous basis for t bli hi t it iestablishing acceptance criteria

• Permit implementation of new technology

• Establish a standard of careEstablish a standard of care

Standards in Construction S ifi iSpecifications

D fi k i f ti b t• Define key information between a buyer and seller to facilitate

d fcommerce and assure performance• Buyer (owner) – established

requirements for materials and construction

• Project contract documents

Specifications on ASR –C El tCommon Elements

• Qualify constituent materials• Qualify constituent materialsUse nonreactive aggregatesLimit alkalies

• Use supplementary cementitious pp ymaterials for mitigation

Fly ash slag silica fume calcined clayFly ash, slag, silica fume, calcined clayBlended cements

U h i l i hibit f• Use chemical inhibitors for mitigation

Test Methods for ASR

• Determine whether proposed materialDetermine whether proposed material or concrete mixture has potential to meet performance requirementsmeet performance requirements

• Evaluate effectiveness of different alternatives to meet performancealternatives to meet performance requirements

• Attempt to accelerate reactions while “predicting” potential field performance

ASTM Tests for ASR Potential(Subcommittee C09.26 – Chemical Reactions)

• ASTM C227—Mortar – Bar Method• ASTM C289—Chemical Method S C 89 C e ca et od• ASTM C441—Mortar Bar/SCMs• ASTM C1260 Rapid Mortar Bar Method• ASTM C1260—Rapid Mortar Bar Method • ASTM C1293—Concrete Prism Test • ASTM C1567—Rapid Mortar Bar/SCMs

ASTM C227, C441 and C1293,“Over Water @ 38 °C”

Sealed Sealed container container in 38in 38 °°CC

Wicking Wicking material on material on

inner surfaceinner surfacein 38 in 38 °°C C roomroom

inner surfaceinner surface

WaterWater

ASTM C1260 and C1567ASTM C1260 and C1567“Immerse in NaOH at 80 °C”

Polypropylene box with cover

1N NaOH SolutionWater Water BathBath 1N NaOH SolutionBathBath

80 80 ±±2 C2 C°°

ASTM ASTM TestTest UseUse

Sample Sample TypeType

Test Test ConditionCondition

Common Common DurationDuration

C227C227 Cem/Agg. Cem/Agg. CombinationCombination

MortarMortar Over HOver H22O O @ 38@ 38°°CC

90, 180d90, 180d@@

C441C441Effect. Of Effect. Of SCM’sSCM’s

Mortar Mortar (Pyrex +(Pyrex +

Over HOver H22O O @ 38@ 38°°CC 14 56d14 56dC441C441 SCM sSCM s (Pyrex + (Pyrex +

HA Cem)HA Cem)@ 38@ 38 CC 14, 56d14, 56d

C1260C1260 AA IIC1260 C1260 and and

[C1567][C1567]

Agg. Agg. [Effect. Of [Effect. Of

SCM’s]SCM’s]MortarMortar

Immerse Immerse NaOH NaOH

@ 80@ 80°°CC14d14d

[C1567][C1567] SCM s]SCM s] @ 80@ 80 CC

C1293C1293Agg. Agg.

[Eff t Of[Eff t OfConcrete Concrete

(Addl(AddlOver HOver H22O O @ 38@ 38°°CC 1 21 2C1293C1293 [Effect. Of [Effect. Of

SCM’s]SCM’s](Addl. (Addl. NaOH)NaOH)

@ 38@ 38°°CC 1 or 2 yr1 or 2 yr

Specifications on ASR –C El tCommon Elements

• Qualify constituent materials• Qualify constituent materialsUse nonreactive aggregatesLimit alkalies

• Use supplementary cementitious pp ymaterials for mitigation

Fly ash slag silica fume calcined clayFly ash, slag, silica fume, calcined clayBlended cements

U h i l i hibit f• Use chemical inhibitors for mitigation

ASTM C33 – Specification f C t A tfor Concrete Aggregates

• “Fine (coarse) aggregate for use in concrete that will be subject to wetting, extended

t h id t h t texposure to humid atmosphere, or contact with moist ground shall not contain any materials that are deleteriously reactive withmaterials that are deleteriously reactive with the alkalies in the cement in an amount sufficient to cause excessive expansion of pmortar or concrete…”

ASTM C33 – Specification f C t A t ( ’t)for Concrete Aggregates (con’t)

• “…except that use of the fine (coarse)aggregate is not prohibited when used with a cement containing less than 0 60 % alkaliescement containing less than 0.60 % alkalies calculated as sodium oxide equivalent (Na2O + 0 658K2O) or with the addition of a material0.658K2O) or with the addition of a material that has been shown to prevent harmful expansion due to the alkali-aggregate gg greaction. (see Appendix X1)”

• Appendix X1 (Nonmandatory) – methods for pp ( y)evaluation of the potential for ASR

ASTM C295ASTM C295

ASTM C295ASTM C295

ASTM C150 – Specification f P tl d C tfor Portland Cement

O i l h i l i• Optional chemical requirement:Max. equiv. alkalies (Na2O + 0.658K2O) = 0 60%0.60%

• “Specify this limit when the cement is to be d i i h hused in concrete with aggregates that are

potentially reactive and no other provisions have been made to protect the concrete fromhave been made to protect the concrete from deleteriously reactive aggregates. Refer to Specification C33 for information on potentialSpecification C33 for information on potential reactivity of aggregates.”

Specifications for Supplementary C i i M i lCementitions Materials

ASTM C itt C01 C t• ASTM Committee C01 on CementASTM C595 – Blended CementASTM C1157 – Performance Hydraulic Cement

ASTM C itt C09 C t d• ASTM Committee C09 on Concrete and Aggregates

ASTM C618 Fl A h d N t lASTM C618 – Fly Ash and Natural PozzolansASTM C989 Slag CementASTM C989 – Slag CementASTM C1240 – Silica Fume

ASTM C595 – Specification f Bl d d C tfor Blended Cement

• Optional physical requirement (C227 with Pyrex):

Max. mortar expansion: 0.020% at 14 daysMax. mortar expansion: 0.060% at 8 weeks

• “The test for mortar expansion is an optional requirement to be applied only at the purchaser’s request and is not required unless the cement will be used with alkali-reactive aggregate ”aggregate.”

ASTM C618 – Specification f Fl A h d N t l P lfor Fly Ash and Natural Pozzolans• Optional physical requirement (C441 as

modified by C311):Expansion of test mixture as percentage of low-alkali cement control - max. 100% at 14 daysdays

• Fly ash or natural pozzolans meeting this requirement are considered as effective inrequirement are considered as effective in controlling ASR as the use of the low-alkali control cement.control cement.

ASTM C618 – Specification f Fl A h d N t l P lfor Fly Ash and Natural Pozzolans

(con’t)( )• Effective only when:

Used at percentages by mass of the total cementitious material equal to or exceeding that used in the testsused in the tests The alkali content of the cement to be used does not exceed that used in the tests by more than 0.05 %.

ASTM C989 – Specification f Sl C tfor Slag Cement

• Appendix X3 (Nonmandatory) – Effectiveness of slag cement in preventing ASR expansion

• “…not considered necessary unless the slag cement is to be used: (a) with a high-alkali portland cement 0 6 % or the concreteportland cement … 0.6 % or the concrete contains added water-soluble alkalies (added as an activator to improve early strength); and (b)an activator to improve early strength); and (b) with an aggregate that is regarded as deleteriously reactive with alkalies.”

ASTM C989 – Specification f Sl C t ( ’t)for Slag Cement (con’t)

• When job cement and proportions of cement to slag cement are known, use C441 with job mixture and expansion at 14 days should notmixture and expansion at 14 days should not exceed 0.020%

• When job cement and proportions not known• When job cement and proportions not known, use C441. Slag cement must reduce expansions of high alkali control by at least 75%, and slagof high alkali control by at least 75%, and slag cement must be used in proportions at least as high as those in the tests.

ASTM ASTM SpecificationSpecification

Test Test MethodMethod

Specification Specification LimitLimit

Test Test ControlControl

C595C595 C227 (Pyrex)C227 (Pyrex)0.020 % @ 14 d0.020 % @ 14 d

0 060 @ 8wk0 060 @ 8wkN/AN/A

0.060 @ 8wk0.060 @ 8wk

C1157C1157 C227 C227 (borosilicate)(borosilicate)

0.020 % @ 14 d0.020 % @ 14 d0.060 @ 56d0.060 @ 56d

N/AN/A( )( ) @@

C989C989(NM Append )(NM Append )

C441C441 0.020% @14d or 0.020% @14d or 75 % reduction75 % reduction

High alkali High alkali cementcement(NM Append.)(NM Append.) 75 % reduction75 % reduction cementcement

C441 (as C441 (as d f dd f d Max 100% ofMax 100% of Low alkali Low alkali

C618C618 modified in modified in C311)C311)

Max. 100% of Max. 100% of Control @14 dControl @14 d cement cement

< 0.60% < 0.60%

2525

C1240C1240 C441C441 At least 80% At least 80% reduction @ 14 dreduction @ 14 d

High alkali High alkali cementcement

Specifications on ASR –C El tCommon Elements

• Qualify constituent materials• Qualify constituent materialsUse nonreactive aggregatesLimit alkalies

• Use supplementary cementitious pp ymaterials for mitigation

Fly ash, slag, silica fume, calcined clayFly ash, slag, silica fume, calcined clayBlended cements

U h i l i hibit f• Use chemical inhibitors for mitigation

ASR Requirements for Concrete M t i l A K Di ti tiMaterials – A Key Distinction

• Qualification of constituent materials• Qualification of constituent materialsProvisions permitting use of a portland cement or SCM in concrete with potentiallycement or SCM in concrete with potentially reactive aggregateAddressed in constituent material specification

• Mitigation of ASRgProvisions for determining the type and amount of SCM or chemical inhibitor to mitigate potential reactionsAddressed in concrete specification

ASR Requirements for Concrete MaterialsQuestions Considered byQuestions Considered by

ASTM C01 and C09 Task Group

• What is the function of ASR requirements in constituent material

ifi i ?specifications?• Can ASR requirements in our various

specifications be rationalized and harmonized?

• Can we develop a concrete specification for ASR that is “linked” to constituent

t i l i t ?materials requirements?