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Performance of a Novel Sustainable Binder Under Extreme Dynamic Loading Conditions

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Performance of a Novel Sustainable Binder Under Extreme Dynamic Loading Conditions University of Rhode Island DigitalCommons@URI Open Access Master's Theses 2017 Performance of a Novel Sustainable Binder Under Extreme Dynamic Loading Conditions Paul David Schmidt University of Rhode Island, [email protected] Follow this and additional works at: https://digitalcommons.uri.edu/theses Recommended Citation Schmidt, Paul David, "Performance of a Novel Sustainable Binder Under Extreme Dynamic Loading Conditions" (2017). Open Access Master's Theses. Paper 1049. https://digitalcommons.uri.edu/theses/1049 This Thesis is brought to you for free and open access by DigitalCommons@URI. It has been accepted for inclusion in Open Access Master's Theses by an authorized administrator of DigitalCommons@URI. For more information, please contact [email protected]. PERFORMANCE OF A NOVEL SUSTAINABLE BINDER UNDER EXTREME DYNAMIC LOADING CONDITIONS BY PAUL DAVID SCHMIDT A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE IN CIVIL AND ENVIRONMENTAL ENGINEERING UNIVERSITY OF RHODE ISLAND 2017 MASTER OF SCIENCE OF PAUL DAVID SCHMIDT APPROVED: Thesis Committee: Major Professor Sumanta Das George Tsiatas Arun Shukla Nasser H. Zawia DEAN OF THE GRADUATE SCHOOL UNIVERSITY OF RHODE ISLAND 2017 ABSTRACT Iron Carbonate is a novel carbon-negative sustainable binder that is made from metallic iron powder waste and utilizes the chemistry of iron carbonation. To produce the binder, usually landfilled iron powder and other constituents (fly ash, limestone powder, metakaolin, sodium carbonate, sodium bicarbonate, powdered organic reducing agent, and water) are mixed together and exposed to a pressurized CO2 regime that leads to slow external diffusion. The carbonation of iron particles results in the formation of complex iron carbonates that have binding capabilities and mechanical properties similar or better compared to ordinary Portland cement (OPC)- based binders. The metallic particulate phase incorporated in the novel binders’ microstructure increases the toughness of Iron Carbonate because of the energy dissipation by plastic deformation of the unreacted and elongated iron particles which are strong and ductile. In addition, the matrix contains other additives including harder fly ash particles, softer limestone particles, and ductile clayey phases which significantly influence the overall fracture performance of the novel sustainable binder. Understanding the behavior of Iron Carbonate at high strain rates is important for a wide range of both military and civilian applications. The material behavior under highly dynamic conditions is significantly different from the material response under quasi-static conditions. The split Hopkinson (Kolsky) pressure bar (SHPB) system is used to test dynamic compressive mechanical response and failure behavior of Iron Carbonate under high strain rates to establish exceptional dynamic load mitigation characteristics for the carbon-negative sustainable binder under extreme combined environments. Dynamic tests are conducted on cylindrical Iron Carbonate specimens using a conventional SHPB set-up. The experimental arrangement includes a gas gun and three steel bars (a striker bar, an incident bar, and a transmitted bar), aligned along a single axis. The Iron Carbonate specimen is placed between the incident and transmitted bar and the striker projectile is fired toward the face of the incident bar. Due to the impact of the striker bar an incident pulse, a reflected pulse and a transmitted pulse are generated that build up the stress level in the specimen and compress it. Objective of the carried out dynamic compression tests on Iron Carbonate specimen is the determination of the stress equilibrium, true stress-strain plots and strain-rate. Analysis of the obtained pulses revealed that the transmitted pulses of the tested Iron Carbonate specimens were of much smaller magnitude than the incident and reflected pulses. As a result, achievement of stress equilibrium and homogeneous deformation of the Iron Carbonate samples was prevented. The small amplitude of the transmitted pulses is due to the possibly low mechanical impedance of Iron Carbonate. Testing specimens made of material with low mechanical impedance allows the incident bar-specimen interface to nearly move freely under stress wave loading, so that most of the incident pulse is reflected backward into the incident bar. Only a small portion of the loading pulse is transmitted through the specimen into the transmission bar. Therefore, the conventionally used experimental standard set-up of the SHPB system using steel bars has to be modified in order to determine accurate dynamic stress-strain responses for Iron Carbonate. To increase the magnitude of the transmitted pulses a softer material, such as aluminum, should be used as transmitted bar material instead of common steel. Furthermore, a hollow transmitted bar instead of a solid bar should be used. The lower Young’s modulus of an aluminum alloy and the smaller cross-section of the hollow bar increase the amplitude of the transmitted strain signals by at least an order of magnitude as compared to a conventional steel bar. ACKNOWLEDGMENTS The author sincerely acknowledges the support from Dr. Arun Shukla and the Dynamic Photomechanics Laboratory of the University of Rhode Island towards the conduct of this study and for the use their facilities. Especially the author would like to thank Koray Senol, Prathmesh Parrikar and Shyamal Kishore for dedicating their time to help setting up the split Hopkinson pressure bar (SHPB) experiment in their laboratory. Furthermore, the author thanks the URI technical staff assistants David Ferreira and Kevin Broccolo. They were extremely helpful in solving issues concerning the cutting of samples, building up the SHPB, and manufacturing missing parts for the experiment. The author acknowledges his advisor and major professor Dr. Sumanta Das and – once again – Dr. Arun Shukla, as well as Dr. George Tsiatas and Dr. Mayrai Gindy for agreeing to serve as members on the authors Master’s Program Committee. Also, the author would like to thank Dr. David Taggart for agreeing to serve as defense committee chair. Samples of the novel binder material were manufactured and provided by Dr. David Stone and his company Iron Shell LLC, which is sincerely acknowledged. v TABLE OF CONTENTS ABSTRACT .............................................................................................. ii ACKNOWLEDGMENTS ......................................................................... v 1 Introduction ........................................................................................12 2 Approaches to improve sustainability in cement manufacture .....14 2.1 Ordinary Portland Cement ........................................................................... 14 2.1.1 Importance of OPC ........................................................................................... 14 2.1.2 History and discovery of Portland Cement ....................................................... 15 2.1.3 Manufacture of OPC ......................................................................................... 16 2.1.4 Carbon Footprint and environmental issues of OPC ........................................ 21 2.1.5 Durability of OPC ............................................................................................. 25 2.1.6 OPC market and future development ................................................................ 27 2.2 General approaches to improve sustainability of cement manufacture ... 29 2.2.1 Definition of sustainable development ............................................................. 29 2.2.2 CO2 reduction plan of the IEA for the cement industry .................................... 29 2.2.2.1 Energy efficiency....................................................................................... 30 2.2.2.2 Utilization of industrial process wastes .................................................... 32 2.2.2.3 Carbon Capture ........................................................................................ 35 2.2.3 Other approaches to reduce the carbon footprint of the cement industry ......... 37 1 2.2.3.1 Nanoengineering ....................................................................................... 37 2.2.3.2 Chemical Admixtures ................................................................................ 40 2.2.3.3 Recycling concrete .................................................................................... 40 2.3 Modification of cement for improved sustainability ................................... 41 2.3.1 Blended OPC-based cements (Supplementary Cementitious Materials) .......... 41 2.3.1.1 Fly ash and pulverized fuel ash (PFA) ..................................................... 42 2.3.1.2 Ground granulated blast furnace slag (GGBS) ........................................ 43 2.3.1.3 Ground limestone ...................................................................................... 44 2.3.1.4 Silica fume ................................................................................................ 45 2.3.1.5 Calcined clay (Metakaolin) ...................................................................... 46 2.3.1.6 Rice husk ash ............................................................................................ 47 2.3.1.7 Other types of supplementary cementitious materials .............................. 47 2.3.2 Alternative cements .........................................................................................
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