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2018 Interground/Blended Cements

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Wally Heyen

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2018 Interground/Blended Cements

  1. 1. OUTLINE • NEBRASKA TESTING FROM 2008 - 2016 • CORRELATING ASTM C1293 WITH FHWA TP-65 (AASHTO R 80) • NEBRASKA TESTING FROM 2016 TO PRESENT • CORRELATING AASHTO T 380 (MINI PRISM TESTING - TP 110) TO ASTM C 1293 • CHANGE IN BLENDED/INTERGROUND CEMENT SPECIFICATION
  2. 2. NEBRASKA STARTED TO LOOK TOWARDS MINIMIZING THE RISK OF ASR
  3. 3. Thomas, Fournier & Folliard, 2008 Determining The Reactivity Of Concrete Aggregates And Selecting Appropriate Measures For Preventing Deleterious Expansion In New Concrete Construction Federal Highways Administration, FHWA-HIF-09-001 National Strategy for Preventing ASR.... First Step – FHWA Protocol – AASHTO R 80
  4. 4. POSTER TEMPLATE BY: www.PosterPresentations.com Nebraska Department of Transportation Evaluation of Statewide Aggregate Reactivity -Phase I LIESKA HALSEY & WALLY HEYEN 2009-2010 NEBRASKA INTRODUCTION The purpose of this investigation is to study the nature of Nebraska‘s aggregates’ reactivity from various locations across the state. The evaluation is based on the standard test methods for Potential Alkali Reactivity of Aggregates-ASTM C 1260 and ASTM C 1567. The ASTM C 1260 determines and characterizes the reactivity of the aggregates within 28 days according to NDOR specifications and ASTM C 1567 determines the mitigation of ASR with the use of supplemental cementitious materials (SCM). Phase I - Materials and Experimental Laboratory Testing: The materials used in this investigation was from 9 different aggregates sources, see Figure 1 below. All testing followed the ASTM C 1260 and ASTM C 1293. The results of length change are shown in Table 1. ANALYSIS OF AGGREGATE REACTIVY ACCORDING TO AASTHO The analyses of the results were based on AASHTO PP 65-10 2010’s special provision guide titled “Determining the Reactivity of Concrete Aggregate and Selecting Appropriate Measures for Preventing Deleterious Expansion in New Construction”. The aggregate degree of aggregate reactivity evaluation was guided as shown in Table 2 with the identification of the reactivity classification according to AASTHO Protocol; followed by determining the level of ASR risk as shown in Figure 2 under all concrete exposed to humid air, buried or immersed due to Nebraska’s winter condition; as well as the classification of the type of the structure shown on Figure 3, which follows Class S3; followed Figure 4 and Figure 5, which covers the minimum replacement level of SCM for various levels of prevention by reactivity classification. Table 2 - Degree of Aggregate Reactivity According to Protocol AASTHO PP-65 The analysis through Phase I evaluation shows that Nebraska’s aggregate, resulted in Moderate to Very Highly Reactive aggregates, as described in Table 3. Comparing the results with NDOR’s current specifications for minimum replacement levels when using SCM, the study found the Elkhorn River and Republican River are Very Highly Reactive aggregates, which required up to 35 percent SCM replacement. The NDOR’s Specification requires up to 25 percent SCM replacement. The continuation of this evaluation will be covered in Phase II using the same aggregates tested in Phase I according to ASTM C 1293 testing (Figure 6) method using Supplemental Cementitious Materials SCM’s percentage currently used in Nebraska. Aggregate- Reactivity Class Description of Agg. Reactivity 1 Year Expansion in CPT (%) 14-Day Expansion in AMPT (%) R0 Non-reactive <0.04 <0.10 R1 Moderate Reactive 0.040 - 0.120 >0.10 , <0.30 R2 Highly reactive 0.120 - 0.240 >0.30 -<0.45 R3 Very highly Reactive > 0.240 > 0.45 Figure 2 - *Determining the Level of ASR Risk Figure 3 - * StructureClassification Figure 4 - * Determining the level of Prevention Table 3 represents the classification according to the AASTHO PP-65 specification, the color code representation follows Table 2 according to the level of reactivity: Table 3.- Summary of Results and Evaluation According to Aggregate Reactivity Figure 5 - *Level of Prevention Figure 1 - Nebraska’s Regions Source of Aggregate Aggregate Location Cementitious Material ASTM C 1260 Results 28 days Duration (%) ASTM C 1293 Results 1 Year Duration (%) Platte River Grand Island Type I/II 0.39 0.09 Dry Pit Kimball Type I/II 0.32 0.21 Republican River Indianola Type I/II 0.48 0.45 North Platte River Scottsbluff Type I/II 0.46 0.15 South Platte River Ogallala Type I/II 0.25 0.06 MiddleLoup River Thedford Type I/II 0.39 0.19 Little Blue River Fairbury Type I/II 0.48 0.10 Elkhorn River Norfolk Type I/II 0.57 0.30 Platte River Linoma- Omaha Type I/II 0.46 0.15 Table 1 - Phase I Evaluation according by ASTM C 1260 and ASTM C 1293 Figure 6 - ASTM C 1293 Specimens Preparation * All Figures are referenced from AASTHO PP 65-10
  5. 5. POSTER TEMPLATE BY: www.PosterPresentations.com Nebraska Department of Transportation Evaluation of Statewide Aggregate Reactivity -Phase II LIESKA HALSEY & WALLY HEYEN 2010-2013 NEBRASKA INTRODUCTION Phase II of the laboratory investigation is currently underway and serves as a continuation of Phase I. Which, analysis of the test results were based on the AASHTO PP 65-10 (2010) special provision guide, “Determining the Reactivity of Concrete Aggregate and Selecting Appropriate Measures for Preventing Deleterious Expansion in New Construction” and ultimately determine the overall level of risk due to ASR. Through Phase I evaluation, it was found that all aggregate pit locations tested resulted in Moderate to Very Highly Reactive aggregates, as described in Table 2. The same aggregate sources analyzed in the initial phase, will be tested according to ASTM C 1293 (Standard Test Method for Determining the Potential Alkali-Silica Reaction) of Combinations of Cementitious Materials using SCM percentage currently specified by NDOR as a IP cement using 25% Class F fly ash replacement (Figure 1). ANALYSIS OF AGGREGATE REACTIVY ACCORDING TO AASTHO PP 65-10 The current evaluation has proven NDOR’s Standard Specification mitigates all currently used aggregate across the state, as summarized in Table 2. In addition, a database will be created that fully categorizes the reactivity of Nebraska’s principal aggregate sources. Also, this study will review past performance of NDOR projects built with SCM’s. This investigation took a look at NDOR project field performance with reactive aggregates from the category of moderate reactive to very highly reactive aggregate, as summarized in Table 3. Field performance analysis were based on the AASHTO PP 65-10 (2010) special provision guide. Comparing the results with NDOR’s current specifications for minimum replacement levels when using SCM, it was found the Elkhorn River a Very Highly Reactive aggregate, which required up to 35 percent SCM replacement, could perform well with replacement up to 25 percent SCM as per AASTHO PP 65-10 states when using a low alkali cement. Figure 4 shows Norfolk East project built with 22 percent interground IP with Class F fly ash field performance. Table 2. Nebraska’s Aggregate Testing with SCM Percentage currently Specified by NDOR Table 2 - Nebraska’s Aggregate Reactivity Classification Aggregate Location ASTM C 1293 Results 1 Year (%) Description of Agg. Reactivity Aggregate Reactivity Class Table 1-Protocol A Grand Island 0.09 Moderate Reactive R1 Kimball 0.21 Highly Reactive R2 Republican River 0.45 Very Highly Reactive R3 Scottsbluff 0.15 Moderate Reactive R2 Ogallala 0.06 Moderate Reactive R1 Thedford 0.19 Highly Reactive R2 Fairbury 0.10 Moderate Reactive R1 Norfolk 0.30 Very Highly Reactive R3 Linoma 0.15 Moderate Reactive R2 Figure 1. Aggregate Location SCM Material ASTM C 1293 Results 2 Years (%) Grand Island IPF(25%ClassFFlyAsh) 0.02 Kimball 0.01 Republican River 0.01 0.02Scottsbluff Ogallala 0.01 Thedford 0.01 Fairbury 0.01 Norfolk 0.01 Linoma 0.03 Route Built Project Number Cement Type Used Source of Aggregate ASTM C 1293 Results 1 Years (%) Min. Replacement Level of SCM to Provide Levels of Prevention Reduce the min. amount of SCM one prevention Level due to low alkali Cement- Table 8 - Protocol A Performance 2011 Chester Hebron 1994 F-81- 1(1017) Type I Added 17% Class F Grand Island 0.10 Moderate Reactive 20% 15% Ansley 2001 S-2-3 (1019) Type I Added 17 % Class F Thedford 0.19 Highly Reactive 25% 20% Norfolk East 1995 275-5- (1013) IPF Interground 22% Class F Norfolk 0.30 Very Highly Reactive 35% 25% Norfolk East 2005 F-275-6 (1020) Led with 98 Spec Type 17% IPN+9% C Norfolk 0.30 Very Highly Reactive 35% 25% Table 3 - Summary of NDOR Projects Field Performance with Reactive Aggregates Performance review provided a good correlation with the special provision guidance of AASHTO PP65-10 (2010). In fact, the protocol correlates well when reviewing the field performance (Figure 2 and 3) of Ansley built in 2001 using highly reactive aggregate with not enough SCM to mitigate the reaction. Figure 3 - Field Performance (Highly Reactive Aggregate) Ansley built 2001 Figure 2 - Field Performance (Highly Reactive Aggregate) Ansley built 2001 Figure 4 - Field Performance (Very Highly Reactive Aggregate) Norfolk East built 1995 The same correlation was found when evaluating the field performance (Figure 5) of Norfolk East built in 2004 using very highly reactive aggregate with not enough prevention measure to mitigate the reaction. Figure 5 - Field Performance (Very Highly Reactive Aggregate) Norfolk East built 2004 The analysis of Phase II is guided by the composition of the ashes being used in the evaluation and the classification of aggregate reactivity as per Protocol A. Phase II is in progress.
  6. 6. Aggregate Type Location Platte River Grand Island Dry Pit Kimball Republican River Indianola North Platte River Scottsbluff South Platte River Ogallala Middle Loup River Thedford Little Blue River Fairbury Elkhorn River Norfolk Platte River Linoma Descripti on of Agg. Reactivity Moderat e Reactive Highly Reactive Very Highly Reactive Highly Reactive Moderat e Reactive Highly Reactive Moderat e Reactive Very Highly (Table 6- AASHTO PP 65-10) Type I/II Cement Low Alkalinity Min. Replacem ent Level of SCM Min. Replacem ent Level of SCM Mitigate ASR 20 15 25 20 35 25 25 20 20 15 25 20 20 15 35 25 Nebraska's Spec Since Late 2004 IP with 25% Class F Republican River Indianola’s Aggregate Non- Approved Aggregate
  7. 7.  Part I - Consisted of using the Mini Concrete Prism Test (AASHTO T 380).  Baseline established by the data from the 2008 study, which utilized the C1293 test method and compare it to the AASHTO T 380.  The goal was to ensure that the same results would be obtained from both tests before the final implementation of AASHTO T 380.
  8. 8. Phase I (ASTM C 1260) Type I/II cement – 28 days testing (Completed)  ASTM C 1260 to find out the aggregates reactivity Phase II Mini Prism Testing (84 days Testing with Type I/II cement) • A- Coarse side of the Linoma aggregate • B- Fine side of the Linoma aggregate • C- 100% Sand and gravel from Linoma • D- 47B (70%-30%) Phase IIIMini Prism Testing (84 days Testing with IP)  A- Coarse side of the Linoma aggregate (S&G)  B- Fine side of the Linoma aggregate  C- 100% Sand and gravel aggregate from Linoma  D- 47B (70%-30%) Phase IV Mini Prism Testing (84 days Testing with Slag)  38% Slag Mini-Prism testing 1. Fine aggregate (Linoma) 2. Fine aggregate (Norfolk) 2016 to Present
  9. 9. Noncompliant material shall be tested in accordance with ASTM C 1567 Alkali Silica Reaction Requirements and Testing: a. Interground/Blended cement shall be tested according to the provisions of ASTM C 1567. (1) The mortar bars shall be composed of Type IP, IS or IT Interground/blended cement and sand and gravel from an approved Platte River Valley-Saunders County source. the highest reactive aggregate incorporated in the project. i. When Elkhorn River-Madison County source or an out of state aggregate source is being used on a project, the Elkhorn River or an out of state aggregate source shall be used in lieu of the Platte River Valley- Saunders County source. ii. When Contractor proposes a change of aggregate source, then the new aggregate source shall be tested by ASTM C 1567. (2) The mortar bars for the ASTM C 1567 shall not exceed 0.10% expansion at 28 days. i. If the expansion is greater than 0.10% at 28 days, then the Interground/Blended cement shall be tested in accordance with AASTHO T 380 using the aggregate from the project with an expansion not greater than 0.02% at 56 days.
  10. 10. • 11.5 days, 10 states & 5100 miles Questions?

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