The Identification and Prevention of Alkali Silica Reactive (ASR) Aggregates

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1 The Identification and Prevention of Alkali Silica Reactive (ASR) Aggregates 2017 Northeastern States Materials Engineers Association (NESMEA) Annual Conference October Hartford, CT

2 John Grieco, PE Director of Research & Materials Richard Mulcahy, EIT Quality Assurance Section of Research & Materials 2017 NESMEA Annual Conference

3 What is Alkali Silica Reaction? qdefinition Ø A Process in which silica (found in aggregate) in the presence of moisture, is broken down by alkalis (sodium and potassium found in cement) and produces an expansive gel. qthree Step Process Ø Alkali + Reactive Silica = Gel Ø Gel + Moisture = Gel Swelling Pressure Ø Gel Swelling Pressure > Concrete Tensile Strength = Concrete Cracking and Failure 2017 NESMEA Annual Conference 3

4 Akali + Reactive Silica = Gel Na + Na + K + OH - ASR Aggregate K + K + Na NESMEA Annual Conference 4

5 Gel + Moisture = Gel Swelling H 2 O H 2 O ASR Aggregate H 2 O H 2 O H 2 O 2017 NESMEA Annual Conference 5

6 Gel Pressure > Tensile Strength H 2 O ASR Aggregate H 2 O H 2 O H 2 O H 2 O 2017 NESMEA Annual Conference 6

7 MassDOT History with ASR q1996 Ø ASR found on Memorial Bridge in Springfield Ø FHWA advised MassDOT to test Aggregates for ASR q1998 Ø MassDOT requires producers to submit certified ASR Test Results Annually Modified AASHTO T 303 Accelerated Mortar Bar Test (AMBT) results annually ASTM C295 Petrographic Examination 2017 NESMEA Annual Conference 7

8 MassDOT History with ASR q 2003 Ø MassDOT performs in-house ASR testing Discrepancy between MassDOT and producer test results Identified an aggregate source used by several producers which was very highly reactive q 2008 Ø MassDOT begins proficiency testing of independent laboratories for Modified AASHTO T303 (AMBT). Ø Established a qualified list of approved testing laboratories based on their proficiency test performance NESMEA Annual Conference 8

9 MassDOT History with ASR q2008 Ø Identified 40 construction projects completed between 7 and 12 years ago that used the very highly reactive aggregate identified in 2003 Ø Developed research program to analyze concrete structures on the 40 projects, determine risk assessment and future management of the structures NESMEA Annual Conference 9

10 ASR Effected Precast Barrier Contract 95505: Somerset-Fall River-Westport-Dartmouth, I-195 East, Precast Barrier At Highland Ave. Bridge 2017 NESMEA Annual Conference 10

11 ASR Effected Sign Foundation Contract 95559: Raynham-Taunton-Norton-Mansfield-Wrentham Sign Foundations, South Bound Exit 8 Route Mile Advance Sign Foundation-Gauge Point Measurement 2017 NESMEA Annual Conference 11

12 ASR Effected Sign Foundation Contract 98106: Bridgewater-Raynham-Taunton-Berkley- Freetown, Exit 14B Route 24 South Bound 2017 NESMEA Annual Conference 12

13 ASR Effected Culvert Contract 96527: Somerset, Route 138 at Read Street, Precast Culvert South Side Riverside Avenue 2017 NESMEA Annual Conference 13

14 ASR Effected Parapet Wall Contract 97343: Middleborough, Miller Street / I-495 South Bound Bottom of Parapet Wall on Outside of Bridge Approximately 12 Left of the Southwest Corner of the Bridge 2017 NESMEA Annual Conference 14

15 MassDOT History with ASR q 2009 Ø MassDOT begins ASTM C1293 Concrete Prism Test (CPT) of a Canadian aggregate source known to be historically highly reactive q 2011 Ø MassDOT is approached by the FHWA to build a long-term ASR Exposure Site q 2012 Ø MassDOT and FHWA break ground on ASR Exposure site on June 6, NESMEA Annual Conference 15

16 MassDOT History with ASR q2016 Ø MassDOT begins experimenting with AASHTO TP 110 Mini Concrete Prism Test (MCPT) q2017 Ø MassDOT begins ASTM C1293 (CPT) on all MassDOT approved aggregate sources Ø 5 year anniversary of the long-term ASR exposure site study 2017 NESMEA Annual Conference 16

17 MassDOT Future with ASR q 2018 Ø MassDOT will perform AASHTO TP 110 (MCPT) on all MassDOT aggregates Ø MassDOT will utilize CCRL Proficiency Program for Independent Laboratory pre-qualification q 2022 Ø 10 year anniversary of the long-term ASR exposure site study Determine if field results correlate with lab tests Prescribe treatments 2017 NESMEA Annual Conference 17

18 Screening for ASR 2017 NESMEA Annual Conference 18

19 Screening for ASR q ASTM C295 Ø Petrographic Examination q AASHTO T 303 Ø Accelerated Mortar Bar Test (14 days) q AASHTO TP 110 Ø Mini Concrete Prism Test (56 to 84 days) q ASTM C 1293 Ø Concrete Prism Test (1 to 2 years) q Long-Term Exposure Site (10 to 20 years) 2017 NESMEA Annual Conference 19

20 ASTM C295 Petrography ASR is identified by the dark areas around the aggregate. This specimen shows ASR gel cracks extending from the aggregate into the surrounding paste NESMEA Annual Conference 20

21 AASHTO T 303 (AMBT) q Duration Ø 14 days q Specimen Size Ø 1 x 1 x NESMEA Annual Conference 21

22 AASHTO T 303 (AMBT) 14-Day Expansion Expected Signs of ASR Reactivity in AMBT, % distress in the Field Nonreactive 0.1 N/A Moderately Reactive >0.1, 0.30 >5 years, <10 years Highly Reactive >0.30, 0.45 <5 years Very highly Reactive >0.45 <5 years 2017 NESMEA Annual Conference 22

23 AASHTO TP 110 (MCPT) q Duration Ø 56 to 84 days (depends on rate of reactivity) q Specimen Size Ø 2 x 2 x NESMEA Annual Conference 23

24 AASHTO TP 110 (MCPT) 56-Day Expansion in MCPT, % Average 2-Week Rate of Expansion from 8 to 12 Weeks Expected Signs of ASR distress in the Field Reactivity Nonreactive 0.03 N/A N/A Nonreactive >0.03, per 2 weeks N/A Low/slow Reactive >0.03, 0.04 >0.01 per 2 weeks >10 years Moderately Reactive >0.04, 0.12 N/A >5 years, <10 years Highly Reactive >0.12, 0.24 N/A <5 years Very highly Reactive >0.24 N/A <5 years 2017 NESMEA Annual Conference 24

25 AASHTO TP 110 (MCPT) Efficiency of Mitigation 56-Day Expansion in MCPT, % Effective Uncertain >0.020, Not Effective > NESMEA Annual Conference 25

26 ASTM C 1293 (CPT) q Duration Ø 1 to 2 years (depends on use of mitigation) q Specimen Size Ø 3 x 3 x 10 Environmental Chamber 2017 NESMEA Annual Conference 26

27 ASTM C 1293 (CPT) 1-Year Expansion Expected Signs of ASR Reactivity in CPT, % distress in the Field Nonreactive 0.04 N/A Moderately Reactive >0.04, 0.12 >5 years, <10 years Highly Reactive >0.12, 0.24 <5 years Very highly Reactive >0.24 <5 years 2017 NESMEA Annual Conference 27

28 Long-Term Exposure Site q Duration Ø 10 to 20 year study on the efficacy of the trialed Treatments q Specimen Size Ø 15 x 15 x 28 q Specimens Ø 73 Blocks 2017 NESMEA Annual Conference 28

29 Long-Term Exposure Site Reactivity 10 to 20 year Expansion (%) Expected Signs of ASR distress in the Field Nonreactive 0.04 N/A Moderately Reactive >0.04, 0.12 >5 years, <10 years Highly Reactive >0.12, 0.24 <5 years Very highly Reactive >0.24 <5 years 2017 NESMEA Annual Conference 29

30 Candidates for Prevention 2017 NESMEA Annual Conference 30

31 Candidates for Prevention Reactivity Class AMBT Range Nonreactive <0.10 Moderately Reactive Highly Reactive Very Highly Reactive >0.45 Agg. ID Coarse Aggregate Mineralogy 1 Diorite (mainly); granitic & volcanic (traces) 2 Mixed Diorite/gneiss/granite/s 0.09 chist 3 Pinkish meta-granite Mixed gneiss/granitic AMBT (14 days) Mass U of DOT Texas Mixed gneiss/schist/quartzite Greywacke/sandstone UT1 Rhyolitic volcanic rocks with quartz and granite 0.62 CPT (360 days) U of Texas Mass DOT NESMEA Annual Conference 31

32 Candidates for Prevention Reactivity Class AMBT Range Agg. ID Nonreactive < Moderately Reactive Highly Reactive Very Highly Reactive > UT2 UT3 Fine Aggregate Mineralogy Mixed gneiss/quartzite/quartz/ feldspar sand Mixed quartzite/gneiss/quartz/ feldspar sand Mixed gneiss/quartzite/quartz/ feldspar sand Mixed gneiss/schist/quartzite/ quartz/feldspar sand Mixed quartz/chert/feldspar sand Mixed quartz/chert sand AMBT (14 days) Mass U of DOT Texas CPT (360 days) Mass DOT U of Texas NESMEA Annual Conference 32

33 Do Lab Test Methods Correlate? 2017 NESMEA Annual Conference 33

34 AASHTO T 303 (AMBT) 14 Day Expansion (%) for 100% Cement Aggregate ID # UT2 UT UT NON- REAC. Circled University of Texas T 303 results differ from MassDOT results quite substantially MOD. REACTIVE HIGHLY REACTIVE VERY HIGHLY REACTIVE 0.0% 0.1% 0.2% 0.3% 0.4% 0.5% 0.6% 14 Day Expansion (%) MASSDOT AASHTO T 303 TEXAS AASHTO T 303 Reactivity Limits 34

35 AASHTO TP 110 (MCPT) 56 Day Expansion (%) for 100% Cement Aggregate ID # UT2 UT UT NON- REAC. Circled TP 110 results differ from what we previously classified to be Highly Reactive from historical T 303 data MOD. REACTIVE HIGHLY REACTIVE VERY HIGHLY REACTIV E 0.00% 0.05% 0.10% 0.15% 0.20% 0.25% 0.30% 56 Day Expansion (%) MASSDOT AASHTO TP 110 (56 DAY) Reactivity Limits 35

36 AASHTO T 303 (AMBT) vs ASTM C1293 (CPT) Expansion (%) for 100% Cement AASHTO T 303 (AMBT) 14 days Expansion (%) 0.60% 0.50% 0.40% 0.30% 0.20% 0.10% MOD. REACTIVE 4 6 HIGHLY REACTIVE % 0.00% 0.10% 0.20% 0.30% 0.40% 0.50% 0.60% ASTM C 1293 (CPT) 1 year Expansion (%) 6 UT3 VERY HIGHLY REACTIVE Circled aggregates cannot be tested with AASHTO T 303 Does not correlate with ASTM C 1293 MassDOT U of Texas Reactivity Limits 36 UT2

37 AASHTO PP 65 AMBT vs ASTM C1293 (CPT) Expansion (%) for 100% Cement AASHTO T days Expansion (%) 0.80% 0.70% 0.60% 0.50% 0.40% 0.30% 0.20% 0.10% UT % 0.00% 0.10% 0.20% 0.30% 0.40% 0.50% 0.60% ASTM C Year Expansion (%) 6 UT3 If AMBT vs. CPT data fall within this range, the AMBT may be used to evaluate preventive measures. Circled aggregates cannot be tested with AASHTO T 303 to evaluate preventive measures MassDOT Results U of Texas Results AASHTO PP 65 Correlation Limits 37 UT2

38 AASHTO TP days Expansion (%) 0.30% 0.25% 0.20% 0.15% 0.10% 0.05% AASHTO TP 110 (MCPT) vs ASTM C1293 (CPT) Expansion (%) for 100% Cement If TP 110 vs. C1293 data fall within the classified range limits, then the MCPT may be used to evaluate ASR MOD. REACTIVE 8 HIGHLY REACTIVE Circled aggregates cannot be tested with TP 110 Does not correlate with C1293 VERY HIGHLY REACTIVE 0.00% 0.00% 0.05% 0.10% 0.15% 0.20% 0.25% 0.30% ASTM C year Expansion (%) MassDOT U of Texas Reactivity Limits 38

39 Clinical Trials (Exposure Site) 2017 NESMEA Annual Conference 39

40 Clinical Trials (Exposure Site) q Duration Ø 10 to 20 year study on the efficacy of the trialed Treatments q Specimen Size Ø 15 x 15 x 28 q Specimens Ø 73 Blocks 2017 NESMEA Annual Conference 40

41 Clinical Trials (Exposure Site) 2017 NESMEA Annual Conference 41

42 Gauge Measurement Locations 2017 NESMEA Annual Conference 42

43 Clinical Trials (Exposure Site) qsimulate qcorrelate qprescribe 2017 NESMEA Annual Conference 43

44 Placebo q33 Placebo (Control) Blocks Ø No preventative measures Ø 10 local aggregates at 3 levels of alkalinity of Portland Cement 0.66, 0.88, and 1.10% Na2Oe Ø 3 non-local aggregates (Texas) at 1.10% Na 2 Oe 2017 NESMEA Annual Conference 44

45 Placebo AGG REACTIVITY BLOCK AGG Na 2 Oe CEM FA SLAG SF LITHIUM % 100% 0% 0% 0% 0% % 100% 0% 0% 0% 0% % 100% 0% 0% 0% 0% Nonreactive % 100% 0% 0% 0% 0% % 100% 0% 0% 0% 0% % 100% 0% 0% 0% 0% % 100% 0% 0% 0% 0% % 100% 0% 0% 0% 0% % 100% 0% 0% 0% 0% % 100% 0% 0% 0% 0% % 100% 0% 0% 0% 0% % 100% 0% 0% 0% 0% % 100% 0% 0% 0% 0% Moderately Reactive % 100% 0% 0% 0% 0% % 100% 0% 0% 0% 0% % 100% 0% 0% 0% 0% % 100% 0% 0% 0% 0% % 100% 0% 0% 0% 0% 49 UT3 1.10% 100% 0% 0% 0% 0% % 100% 0% 0% 0% 0% % 100% 0% 0% 0% 0% Highly Reactive % 100% 0% 0% 0% 0% % 100% 0% 0% 0% 0% % 100% 0% 0% 0% 0% % 100% 0% 0% 0% 0% % 100% 0% 0% 0% 0% % 100% 0% 0% 0% 0% % 100% 0% 0% 0% 0% Very Highly Reactive % 100% 0% 0% 0% 0% % 100% 0% 0% 0% 0% % 100% 0% 0% 0% 0% 15 UT1 1.10% 100% 0% 0% 0% 0% 2017 NESMEA Annual Conference 48 UT2 1.10% 100% 0% 0% 0% 0% 45

46 Preventative Treatments 2017 NESMEA Annual Conference 46

47 Preventative Treatments qasr only occurs if ALL THREE Conditions are met! Eliminate One! REACTIVE SILICA SUFFICIENT ALKALI SUFFICIENT MOISTURE 2017 NESMEA Annual Conference 47

48 Preventative Treatments qnonreactive Aggregate qfly Ash qslag qsilica Fume qlithium qlow Alkali Cement 2017 NESMEA Annual Conference 48

49 Preventative Treatments q 40 Treatment (Preventative Measure) Blocks Ø 4 of the most reactive local Candidates (Aggregates) chosen Ø 2 levels of alkalinity of Portland Cement 0.88 and 1.11% Na 2 Oe Ø 7 preventative measures 20% Class F fly ash 30% Class F fly ash 35% slag 50% slag 4% silica fume + 15% fly ash 4% silica fume + 20% slag 100% standard dose of lithium nitrate (0.55 gal of 30% lithium nitrate per pound of Na 2 Oe) 2017 NESMEA Annual Conference 49

50 Preventative Treatments MODERATELY REACTIVE AGGREGATE BLOCK AGG Na 2 Oe CEM FA SLAG SF LITHIUM % 65% 0% 35% 0% 0% % 50% 0% 50% 0% 0% % 80% 20% 0% 0% 0% % 70% 30% 0% 0% 0% % 100% 0% 0% 0% 100% % 76% 0% 20% 4% 0% % 65% 0% 35% 0% 0% % 50% 0% 50% 0% 0% % 81% 15% 0% 4% 0% % 80% 20% 0% 0% 0% % 70% 30% 0% 0% 0% 2017 NESMEA Annual Conference 50

51 Preventative Treatments HIGHLY REACTIVE AGGREGATE BLOCK AGG Na 2 Oe CEM FA SLAG SF LITHIUM % 100% 0% 0% 0% 100% % 65% 0% 35% 0% 0% % 50% 0% 50% 0% 0% % 81% 15% 0% 4% 0% % 80% 20% 0% 0% 0% % 76% 20% 0% 4% 0% % 70% 30% 0% 0% 0% 2017 NESMEA Annual Conference 51

52 Preventative Treatments VERY HIGHLY REACTIVE BLOCK AGG Na 2 Oe CEM FA SLAG SF LITHIUM % 65% 0% 35% 0% 0% % 65% 0% 35% 0% 0% % 50% 0% 50% 0% 0% % 50% 0% 50% 0% 0% % 80% 20% 0% 0% 0% % 80% 20% 0% 0% 0% % 70% 30% 0% 0% 0% % 70% 30% 0% 0% 0% % 100% 0% 0% 0% 100% % 100% 0% 0% 0% 100% % 76% 0% 20% 4% 0% % 65% 0% 35% 0% 0% % 65% 0% 35% 0% 0% % 50% 0% 50% 0% 0% % 50% 0% 50% 0% 0% % 81% 15% 0% 4% 0% % 81% 15% 0% 4% 0% % 80% 20% 0% 0% 0% % 80% 20% 0% 0% 0% % 76% 20% 0% 4% 0% % 70% 30% 0% 0% 0% % 70% 30% 0% 0% 0% 2017 NESMEA Annual Conference 52

53 Clinical Trials: Day 1828 (5 yr) qwhich Patients really need preventative treatment? Ø Patients that exhibit expansions >0.04 are considered to need preventative treatment 2017 NESMEA Annual Conference 53

54 Long-term Exposure Site Expansion (%) for 1.10% Na 2 Oe*; 100% Cement Note* Aggregate 1 was tested using 0.88% Na 2 Oe; Aggregate 9 is being tested twice Aggregate ID # UT2 UT UT VERY HIGHLY REACTIVE Circled Exposure Site results currently differ from what we previously classified the reactivity of these aggregates from historical T 303 data 0.00% 0.10% 0.20% 0.30% 0.40% 0.50% 0.60% 0.70% 0.80% 0.90% 1.00% 1.10% 5 Year Expansion (%) MassDOT Reactivity Limits 54

55 ASTM C Year Expansion (%) 0.60% 0.50% 0.40% 0.30% 0.20% 0.10% ASTM C1293 (1 Year) vs Long-term Exposure Site (5 Year) Expansion (%) for 100% Cement If C1293 vs. Exposure Site data fall within the classified range limits, then the C1293 correlates with the LTES, thus validating the results 0.00% 0.00% 0.20% 0.40% 0.60% 0.80% 1.00% Long-term Exposure Site 5 Year Expansion (%) 6UT3 6 UT1 Circled Exposure Site results do not currently correlate with C1293 VERY HIGHLY REACTIVE MassDOT U of Texas Reactivity Limits 55

56 Clinical Trials: Day 1828 (5 yr) qhow well are the Low Alkali treatments working? Na + X X Na X + K + XO ASR H - Aggregate XK + X X K + Na NESMEA Annual Conference 56

57 1.00% 100% Cement; Aggregate No. 1 (Nonreactive) 0.90% Portland Cement Na 2 Oe (%) 0.80% 0.70% 0.60% 0.50% 0.40% 0.30% 0.20% MOD. REACTIVE HIGHLY REACTIVE VERY HIGHLY REACTIVE 0.10% 0.00% 0.00% 0.08% 0.16% 0.24% 0.32% 0.40% 0.48% 5 Year Expansion (%) Non-Reactive Aggregate No. 1 57

58 Portland Cement Na 2 Oe (%) 1.20% 1.00% 0.80% 0.60% 0.40% 0.20% 100% Cement; Aggregate No. 6 (Very Highly Reactive) MOD. REACTIVE HIGHLY REACTIVE y = x R² = VERY HIGHLY REACTIVE 0.00% 0.00% 0.08% 0.16% 0.24% 0.32% 0.40% 0.48% 5 Year Expansion (%) Very Highly Reactive Aggregate No. 6 Linear Trendline 58

59 Portland Cement Na 2 Oe (%) 1.20% 1.00% 0.80% 0.60% 0.40% 0.20% 100% Cement; Aggregate No. 10 (Highly Reactive) MOD. REACTIVE y = x R² = HIGHLY REACTIVE VERY HIGHLY REACTIVE 0.00% 0.00% 0.08% 0.16% 0.24% 0.32% 0.40% 0.48% 5 Year Expansion (%) Highly Reactive Aggregate No. 10 Linear Trendline 59

60 Clinical Trials: Day 1828 (5 yr) qhow well are the Mitigation treatments working? Ø Fly Ash Ø Slag Ø Silica Fume Ø Lithium 2017 NESMEA Annual Conference 60

61 Long-term Exposure Site Expansion (%) for Aggregate No. 5 (Very Highly Reactive) Block Identification No % FA 20% FA 15% FA; 4% SF 50% SLAG 35% SLAG 20% SLAG; 4% SF LITHIUM 100% CEM 30% FA 20% FA 50% SLAG 35% SLAG 100% CEM 100% CEM -0.01% 0.00% 0.01% 0.02% 0.03% 0.04% 0.05% 0.06% 0.07% 0.08% 0.09% 5 Year Expansion (%) Very Highly Reactive Aggregate No % Alkalinity ASTM C1293 Reactivity Limit 1.10% Alkalinity 0.88% Alkalinity 61

62 Long-term Exposure Site Expansion (%) for Aggregate No. 10 (Highly Reactive) 34 30% FA 37 20% FA; 4% SF Block Identification No % FA 15% FA; 4% SF 50% SLAG 35% SLAG LITHIUM 100% CEM 1.10% Alkalinity % CEM 100% CEM 0.88% Alkalinity 0.66% Alkalinity 0.00% 0.01% 0.02% 0.03% 0.04% 0.05% 0.06% 0.07% 0.08% 1645 Day Expansion (%) Very Highly Reactive Aggregate No. 6 ASTM C1293 Reactivity Limit 62

63 Long-term Exposure Site Expansion (%) for Aggregate No. 6 (Very Highly Reactive) Block Identification No % FA 20% FA; 4% SF 20% FA 15% FA; 4% SF 50% SLAG 35% SLAG LITHIUM 100% CEM 30% FA 20% FA 50% SLAG 35% SLAG 100% CEM 100% CEM 0.00% 0.05% 0.10% 0.15% 0.20% 0.25% 0.30% 0.35% 0.40% 0.45% 1645 Day Expansion (%) Very Highly Reactive Aggregate No % Alkalinity 0.88% Alkalinity 0.66% Alkalinity ASTM C1293 Reactivity Limit 63

64 Patient: UT 2 (Jobe, TX), No NESMEA Annual Conference 64

65 Patient: UT 2 (Jobe, TX), No % 1.40% 1.20% Expansion (%) 1.00% 0.80% 0.60% 0.40% 1.16% Average Expansion (that s a lot)! 0.20% 0.00% Time (Days) TOP BACK TOP FRONT FRONT BACK LEFT SIDE RIGHT SIDE TOP RIGHT TOP LEFT AVERAGE 2017 NESMEA Annual Conference 65

66 MassDOT Moving Forward q Evaluate Exposure Site (10 to 20 yrs) q Establish Trends q Correlate Field Performance with Lab Tests q Verify Aggregate Reactivity q Decrease ASR Lab Test Frequency q Implement AASHTO TP 110 (56 84 Days) and ASTM C 1293 (1 2 Years) q Identify appropriate preventative Treatment to MassDOT aggregates to slow down or eliminate ASR 2017 NESMEA Annual Conference 66

67 Conclusion q Eliminate only ONE of the three conditions to eliminate ASR all together q Screen Patients for ASR using various laboratory test methods q Prescribe the proper treatment and dosage of medicine to the Patients q Remember! Different Patients may react drastically dissimilar to the same medicine! q Identify Nonreactive / reactive aggregates with confidence q Correlate aggregates with appropriate lab tests 2017 NESMEA Annual Conference 67

68 Conclusion qthere is no Silver Bullet 2017 NESMEA Annual Conference 68

69 Questions and Comments 2017 NESMEA Annual Conference 69

THE EFFECT OF SILICA FUME AND FLY ASH ON ALKALI-SILICA REACTION (ASR) Kamile TOSUN Halit YAZICI Bülent BARADAN Civil Engineering Department

THE EFFECT OF SILICA FUME AND FLY ASH ON ALKALI-SILICA REACTION (ASR) Kamile TOSUN Halit YAZICI Bülent BARADAN Civil Engineering Department ALKALI-SILICA REACTION (ASR) in CONCRETE IS an EXPANSIVE CHEMICAL