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From page 42... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 42 APPENDIX: HYPOTHETICAL CASE STUDY Introduction Objective of Hypothetical Case Study A methodology for designing hydraulic cement concrete mixtures incorporating supplementary cementitious materials that will result in enhanced durability of cast-in-place concrete bridge decks was developed using a statistically based experimental design approach under NCHRP Project 18-08A. This process is detailed in NCHRP Report 566: Guidelines for Concrete Mixtures Containing Supplementary Cementitious Materials to Enhance Durability of Bridge Decks and consists of the following six steps: Step 1: Define Concrete Performance Requirements Step 2: Select Durable Raw Materials Step 3: Generate the Experimental Design Matrix Step 4: Perform Testing Step 5: Analyze Test Results and Predict the Optimum Mixture Proportions Step 6: Perform Confirmation Testing and Select Best Concrete To evaluate the effectiveness of this Methodology, a case study, called the Hypothetical Case Study, chosen as a bridge deck in a northern, Midwest environment subject to freezing and thawing and deicing salt exposure, was investigated. Read the entire page →
From page 43... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 43 Step 1: Define Concrete Performance Requirements Based on a bridge deck application in a northern climate, Figure S1.1 was used to characterize the design requirements and issues relevant to a freezing climate subjected to chemical deicers, where cracking was a concern. This environment was assumed to be neither coastal nor abrasive. Read the entire page →
From page 44... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 44 Table A-1. Completed Worksheet S1.1 for the Hypothetical Case Study Environment Property/Test Method Target Value for Test Method Range of Class C Fly Ash Range of Class F Fly Ash Range of GGBFS Range of silica fume Range of other SCM w/cm Aggregate restrictions Specified aggregate top size Specified cement content Other requirements Compressive strength: AASTHO T 22, ASTM C 143 4,500 - 8,000 psi 0-30 0-30 15-50 5-8 0.44-0.37 f ' c > 4500 psi Flexural strength: AASTHO T 177, T 97, or T 198, ASTM C 293, C 78, or C 496 Slump and Slump loss: AASHTO T 119, ASTM C 143 Max 8-in.; Max. Read the entire page →
From page 45... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 45 Step 2: Select Durable Raw Materials The objective of Step 2 is the selection of suitable raw materials. The worksheets in Step 2 of NCHRP Report 566 were used to organize the available information regarding the locally available materials and facilitate these decisions. Read the entire page →
From page 46... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 46 Table A-2. Completed Worksheet S2.1, list of available raw materials Raw Material Source 1 Source 2 Source 3 Source 4 Cement Cemsource 1 Cemsource 2 Fine aggregate Fineagg manufacturer 1 Fineagg manufacturer 2 Coarse aggregate Coarseagg manufacturer 1 Coarseagg manufacturer 2 Class C fly ash C-ashsource 1 C-ashsource 2 Class F fly ash F-ashsource 1 Ground granulated blast furnace slag Slagsource 1 Slagsource 2 Silica fume Silica fume source 1 Other SCM Air entraining admixture Air 1 Chemical admixture Super X Super Y Chemical admixture Other: Fffffff Selected for use Read the entire page →
From page 47... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 47 Table A-3. Completed Worksheet S2.2, Cement data Test/Property AASHTO Limit Cement 1 Cement 2 Cement 3 Cement 4 Manufacturer Cemsource 1 Cemsource 2 Plant location Anytown Ourtown Mill report date Apr 03 Aug 01 AASHTO M 85 (ASTM C 150) Read the entire page →
From page 48... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 48 Table A-4. Completed Worksheet S2.3, Fine aggregate data Test/Property AASHTO M 6 Class A Limit Local Requirements Fine Agg. Read the entire page →
From page 49... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 49 Table A-5. Completed Worksheet S2.4, Coarse aggregate data Test/Property AASHTO M 80 Class A Requirements† Local Requirement IDOT Class A Coarse Agg. Read the entire page →
From page 50... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 50 Table A-6. Completed Worksheet S2.5, Class C fly ash data Test/Property AASHTO M 295 Requirement Fly Ash 1 Fly Ash 2 Fly Ash 3 Fly Ash 4 Manufacturer C-ashsource 1 C-ashsource 2 Source/plant location Anytown Ourtown SiO2+Al2O3+Fe2O3, % ≥ 50.0 59.9 59.2 CaO, % 27.7 27.4 SO3, % ≤ 5.0 2.01 1.99 Moisture content, % ≤ 3.0 0.06 0.06 Loss on ignition, % ≤ 5.0 0.21 0.40 Amt. Read the entire page →
From page 51... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 51 Table A-7. Completed Worksheet S2.6, Class F fly ash data Test/Property AASHTO M 295 Requirement Fly Ash 1 Fly Ash 2 Fly Ash 3 Fly Ash 4 Manufacturer F-ashsource 1 Source/plant location Anytown SiO2+Al2O3+Fe2O3, % ≥ 70.0 90.5 CaO, % 2.70 SO3, % ≤ 5.0 0.82 Moisture content, % ≤ 3.0 0.14 Loss on ignition, % ≤ 5.0 1.61 Amt. Read the entire page →
From page 52... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 52 Table A-8. Completed Worksheet S2.8, Ground granulated blast-furnace slag (GGBFS) Read the entire page →
From page 53... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 53 Table A-9. Completed Worksheet S2.9, Silica fume data Test/Property AASHTO M 307 Value Silica fume 1 Silica fume 2 Silica Fume 3 Silica fume 4 Manufacturer Silicafume source 1 Source/plant location Anytown SiO2, % ≥ 85.0 89.1 Moisture content, % ≤ 3.0 n/a Loss on ignition, % ≤ 6.0 1.16 Optional: moisture content of dry microsilica, % ≤ 3.0 Optional: available alkalis as Na2O, % ≤ 1.5 Strength activity index: With portland cement at 7 and 28 days, min. Read the entire page →
From page 54... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 54 Table A-10. Completed Worksheet S2.10, air entraining agent (AEA) Read the entire page →
From page 55... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 55 Step 3: Generate the Experimental Design Matrix The completed Worksheet S3.1 (Table A-11) shows the final choices made in Step 1 and 2 from the recommendations developed in Worksheets S1.1 and S2.1. Read the entire page →
From page 56... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 56 Table A-11. Completed Worksheet S3.1, factors, levels, and constants to test for Hypothetical Case Study Factor Level 1 Level 2 Level 3 First SCM Type Class C fly ash Class F fly ash GGBFS Type Factors Source Factors First SCM Amount Low Medium High Amount of Silica fume 0 5 8 w/cm 0.45 0.37 Amount Factors Type Constants Cement Cemsource 2 Fine aggregate Fineagg manufacturer 2 Coarse aggregate Coarseagg manufacturer 1 Class C fly ash C-ashsource 1 Class F fly ash F-ashsource 1 GGBFS Slagsource 2 Silica fume Silica fume source 1 Air entraining agent Air 1 HRWR Super X Source Constants Cementitious Content 658 lb/yd3 Coarse aggregate amount 1696 lb/yd3 Air content 6.5 ± 1.5% Amount Constants Read the entire page →
From page 57... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 57 Table A-12. Worksheet S3.2 completed for compound factor for Hypothetical Case Study Factor 1, Factor 2 Type of SCM Amount of SCM Type 1, Low level Class C fly ash 15% Type 1, Medium Level Class C fly ash 25% Type 1, High Level Class C fly ash 40% Type 2, Low level Class F fly ash 15% Type 2, Medium Level Class F fly ash 25% Type 2, High Level Class F fly ash 40% Type 3, Low level slag 25% Type 3, Medium Level slag 35% Type 3, High Level slag 50% Table A-13. Read the entire page →
From page 58... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 58 coarse aggregate. The intent of this mixture was to provide a comparison to assess relative performance of mixtures with SCMs. Read the entire page →
From page 59... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 59 Table A-16. Concrete test mixtures as batched Mixture ID C1 1 2 3 4 5 6 7 8 9 C2 BTC (8) Read the entire page →
From page 60... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 60 Step 4: Perform Testing The test program outlined in Step 1 (as shown in Worksheet S1.1, Table A-1) was modified slightly in practice and the actual program is given in Table A-17. Read the entire page →
From page 61... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 61 Table A-17. Program for testing of design matrix Property Target Values Test Methods Specimen Size and Number of Specimens Curing Total air content, plastic concrete 6.5 +/- 1.5% AASHTO T 152 _ N/A Max. Read the entire page →
From page 62... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 62 Figure A-1. Batching of concrete Figure A-2. Read the entire page →
From page 63... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 63 Finishing Data Worksheet 2002.2229 1D Mix Number ______________________ Date ____________________________ Concrete Temperature _______________ Air Temperature ___________________ Relative Humidity ___________________ 1 2 3 4 5 Stickiness Creaminess 1 2 3 4 5 Segregation Homogeneity 1 2 3 4 5 Harshness Smoothness 1 2 3 4 5 Prone to Tearing Tear Resistant Figure A-3. Finishability worksheet used to collect data Read the entire page →
From page 64... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 64 Table A-18. Plastic concrete results Mixture Description * Read the entire page →
From page 65... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 65 Measurement of Cracking Potential Three tests were conducted to assess cracking potential. The first was cracking tendency, AASHTO PP34-99 (the restrained shrinkage test) Read the entire page →
From page 66... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 66 Figure A-5. Ring storage and data collection in 50% RH laboratory environment -150 -130 -110 -90 -70 -50 -30 -10 10 30 50 0 20 40 60 80 100 Drying time (days) Read the entire page →
From page 67... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 67 Table A-19. Cracking potential test results Mixture Description (% by wt.) Read the entire page →
From page 68... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 68 Figure A-7. A thermocouple was placed in the center of each concrete cylinder Figure A-8. Read the entire page →
From page 69... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 69 0 10 20 30 40 50 60 0 20 40 60 80 100 120 140 Elapsed Time (hrs.) Read the entire page →
From page 70... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 70 Table A-20. Hardened concrete properties Mixture Description (% by wt.) Read the entire page →
From page 71... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 71 0 1000 2000 3000 4000 5000 6000 7000 8000 9000 0 10 20 30 40 50 60 Age (Days) Read the entire page →
From page 72... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 72 Mixture C1 Mixture 1 Mixture 2 Mixture 3 Mixture 4 Mixture 5 Figure A-12. Freeze/thaw specimens for Mixture C1 and Mixtures 1 to 5 after 300 cycles. Read the entire page →
From page 73... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 73 Mixture 6 Mixture 7 Mixture 8 Mixture 9 Figure A-13. Freeze/thaw specimens for Mixtures 6 to 9 after 300 cycles. Read the entire page →
From page 74... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 74 Table A-21. Durability assessment test results: freeze/thaw and salt scaling tests Mixture Description (% by wt.) Read the entire page →
From page 75... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 75 Mixture C1 Mixture 1 Mixture 2 Mixture 3 Mixture 4 Mixture 5 Figure A-15. Salt scaling slabs for Mixture C1 and Mixtures 1 to 5 after 50 cycles Read the entire page →
From page 76... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 76 Mixture 6 Mixture 7 Mixture 8 Mixture 9 BTC BPC Figure A-16. Salt scaling slabs for Mixtures 6 to 9, BTC and BPC after 50 cycles Read the entire page →
From page 77... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 77 The resistance of the concrete to chloride permeability was estimated using AASHTO T 277 (the electrical conductivity test or RCP test) Read the entire page →
From page 78... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 78 Diffusion fits were generated for each of the three cores individually and the average apparent diffusion coefficient for each mixture was calculated from these values. A brief discussion of how this fitting is performed is provided in NCHRP Report 566. Read the entire page →
From page 79... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 79 Step 5: Analyze Test Results and Predict the Optimum Mixture Proportions After the tests were conducted in Step 4, the responses were tabulated and converted into individual desirability values based on the initially assumed desirability functions. The results of this analysis were reviewed and the responses to be included in the overall desirability calculations were re-evaluated. Read the entire page →
From page 80... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 80 Table A-23. Responses used for calculation of overall desirabilities Proposed Responses from Step 1 Selected Responses for Step 5 Design Matrix Analysis Selected Responses for Step 6 Confirmation Analysis 1. Read the entire page →
From page 81... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 81 0 0.2 0.4 0.6 0.8 1 0 2000 4000 6000 8000 10000 12000 Compressive Strength (psi) D es ira bi lit y Desirability Function Actual Data Controls Mix #6 D es ira bi lit y Figure A-19. Read the entire page →
From page 82... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 82 0 0.2 0.4 0.6 0.8 1 0 20 40 60 80 100 Temperature Rise ('F) D es ira bi lit y Original Desirability Function Revised Desirability Function Actual Data Controls Figure A-20. Read the entire page →
From page 83... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 83 Table A-24. Individual response desirabilities and overall desirabilities for design matrix testing Mixture Property C1 1 2 3 4 5 6 7 8 9 C2 Initial Set 1 1 1 0.8340 1 1 1 1 1 1 1 Finishability 0.9856 0.9725 0.8850 0.9425 0.9075 0.9688 0.9744 0.9500 0.9325 0.9600 0.9706 Cracking Tendency 0.9889 1 1 1 1 0.9833 0.9722 1 0.9556 1 0.9889 Heat of Hydration Temp. Read the entire page →
From page 84... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 84 The BPC was found by evaluating the overall desirability, calculated based on the desirabilities for the individual predicted responses, for many combinations of factor levels until the specific combination that produced the highest overall desirability was identified. These combinations were generated by increasing each factor successively by a small increment to fully describe the test range. Read the entire page →
From page 85... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 85 Table A-26. Predicted responses of Best Tested (BTC) Read the entire page →
From page 86... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 86 Step 6: Perform Confirmation Testing and Select Best Concrete In Step 6, the BPC and BTC were tested according to a revised list of test methods outlined in Table A-27. Table A-23 lists the responses that were included in the calculation of the overall desirability for the Confirmation Testing. Read the entire page →
From page 87... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 87 mm) of the surface, using a machinist's lathe and cutter as shown in Figure A-21. Read the entire page →
From page 88... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 88 For the Hypothetical Case Study, the actual and predicted performances of the Confirmation BTC and BPC agreed very well. The difference between the actual BPC and BTC performance is nearly nine times greater than the difference between the Original and Confirmation Batch of the BTC. Read the entire page →
From page 89... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 89 Table A-29. Comparison of individual responses and desirabilities for BTC Individual Responses Individual Desirabilities Property Original BTC Batch (Mixture #8) Read the entire page →
From page 90... ... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 90 Table A-30. Comparison of individual responses and desirabilities for BPC Individual Responses Individual Desirabilities Property BPC Confirmation Test BPC Prediction BPC% Difference Response BPC Confirmation Test BPC Prediction BPC % Difference Desirability Included in Confirmation Test? Read the entire page →

From page 42...

... NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks 42 APPENDIX: HYPOTHETICAL CASE STUDY Introduction Objective of Hypothetical Case Study A methodology for designing hydraulic cement concrete mixtures incorporating supplementary cementitious materials that will result in enhanced durability of cast-in-place concrete bridge decks was developed using a statistically based experimental design approach under NCHRP Project 18-08A. This process is detailed in NCHRP Report 566: Guidelines for Concrete Mixtures Containing Supplementary Cementitious Materials to Enhance Durability of Bridge Decks and consists of the following six steps: Step 1: Define Concrete Performance Requirements Step 2: Select Durable Raw Materials Step 3: Generate the Experimental Design Matrix Step 4: Perform Testing Step 5: Analyze Test Results and Predict the Optimum Mixture Proportions Step 6: Perform Confirmation Testing and Select Best Concrete To evaluate the effectiveness of this Methodology, a case study, called the Hypothetical Case Study, chosen as a bridge deck in a northern, Midwest environment subject to freezing and thawing and deicing salt exposure, was investigated.