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Impact Of Detergent Type, Detergent Concentration, And Friction Modifiers On Pm-Pn Emissions In An Si Engine Using Eeps, Siddharth Gopujkar, Nic Tuma, Rick Davis, Jeffrey Naber, Elana Chapman, Veronica Reilly, Joseph Ciaravino, Philipp Seyfried Sep 2025

Impact Of Detergent Type, Detergent Concentration, And Friction Modifiers On Pm-Pn Emissions In An Si Engine Using Eeps, Siddharth Gopujkar, Nic Tuma, Rick Davis, Jeffrey Naber, Elana Chapman, Veronica Reilly, Joseph Ciaravino, Philipp Seyfried

Michigan Tech Publications

Three TOP TIERTM gasoline deposit control additives (DCAs) of differing chemistries were tested for their impact on particulate matter emissions in terms of particulate mass (PM) and particle number (PN) at operating conditions representative of road load, cold start, and high load on a 2.0 L, 4-cylinder, gasoline direct injection (GDI) spark ignition (SI) engine. The PM-PN emissions were measured using an Exhaust Emissions Particle Sizer (EEPS). Deposit control additives or detergents are gasoline additives used to prevent and clean combustion chamber and injector deposits in gasoline spark ignition (SI) engines. All three gasoline additives were tested at each …

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The Synergy Between Sfrc And Structural Steel In Increasing The Ductility Of Composite Structures, Gonzalo Ruiz, Ángel De La Rosa, Vaibhav W. Masih, Riccardo Zanon Sep 2025

The Synergy Between Sfrc And Structural Steel In Increasing The Ductility Of Composite Structures, Gonzalo Ruiz, Ángel De La Rosa, Vaibhav W. Masih, Riccardo Zanon

C3 Symposium 2025

Our research on the compressive behavior of steel-fiber reinforced concrete (SFRC) led to a constitutive model in Annex L ofthe new Eurocode 2. This recognition piqued the interest of ArcelorMittal, who requested that we explore the implications of increased compression ductility for composite structures, particularly beams with embedded structural steel sections. The findings from this research demonstrate that the compressive ductility of SFRC enables us to fully utilize the tensile capacity of structural steel in composite structures, resulting in unprecedented levels of structural ductility.

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Fiber Reinforced Concrete Composites - Seminal Contributions Of Surendra Shah, Vellore S. Gopalaratnam, Wengui Li Sep 2025

Fiber Reinforced Concrete Composites - Seminal Contributions Of Surendra Shah, Vellore S. Gopalaratnam, Wengui Li

C3 Symposium 2025

The authors review the scholarly contributions of Surendra P. Shah during a prolific six-decade academic career in fiber reinforced concrete composites. This compilation includes discussions on often cited seminal publications encompassing experimental mechanics, analytical modeling, the development of test standards, materials characterization and innovations in the science of fiber reinforced concrete (FRC) materials. Collectively, these contributions have greatly improved our insights on how the nano- and micro-mechanics of such composites and processing techniques affect the macroscopic performance of creatively engineered reinforced cement composites. Starting with his Ph.D. the first contribution to understanding the inelastic behavior and fracture of concrete, the …

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Fresh And Mechanical Properties Of The Ultra-High-Performance Concrete With Cellulose Nanofibers, Xiaoli Xiong, Chengcheng Tao, Kamal H. Khayat Sep 2025

Fresh And Mechanical Properties Of The Ultra-High-Performance Concrete With Cellulose Nanofibers, Xiaoli Xiong, Chengcheng Tao, Kamal H. Khayat

C3 Symposium 2025

Water-sensitive cellulose significantly impacts the performance of the ultra-high-performance concrete (UHPC), leading to variations in its fresh and mechanical properties of fresh and hardened concrete materials. In this study, the cellulose nanofibers, a more environmentally friendly class of nanomaterials, are introduced into UHPC. The rheological and mechanical properties of UHPC are investigated, including viscosity, yield stress and compressive strength. The results reveal significant effect of cellulose nanofibers on the properties of UHPC in terms of material performance and sustainability. Advanced characterization techniques, including isothermal calorimetry, thermogravimetric analysis (TGA), and X-ray diffraction (XRD) are employed to study the effect of cellulose …

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Upcycled Medical Hemp Fibers For Enhancing Tensile Strength And Fire Resistance Of High-Strength Concrete, Ahmed Almaadawy, Liahneli Knowles, Abigail Lazier, Srishti Banerji, Zach Haber, Bruce Bugbee Sep 2025

Upcycled Medical Hemp Fibers For Enhancing Tensile Strength And Fire Resistance Of High-Strength Concrete, Ahmed Almaadawy, Liahneli Knowles, Abigail Lazier, Srishti Banerji, Zach Haber, Bruce Bugbee

C3 Symposium 2025

This research investigates fire and tensile resistance of high-strength concretes employing fibers extracted from waste medical hemp stalks. Environmental impact analysis of hemp-based solutions is also considered.

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Hempcrete As Low Carbon Solution For Thermal Retrofitting Of Buildings, Rotem Haik, Dor Lazar, Alva Peled Sep 2025

Hempcrete As Low Carbon Solution For Thermal Retrofitting Of Buildings, Rotem Haik, Dor Lazar, Alva Peled

C3 Symposium 2025

Thermal mortars are developed with hemp shives and pozzolans for thermal retrofitting of cultural heritage buildings, including concrete architecture from the 50s. The goal is to improve the thermal performance of the building, while reducing the carbon footprint. This research is within the framework of European Union’s Horizon 2020 (Sincere). A range of mixtures were developed based on standard mortar for plaster, as a reference. The research investigates the possibility of partly replacing the cement with pozzolans, as well as the sand in the mortar with fine hemp shives, to obtain lower EE and EC of the mixture, as compared …

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Durability Of Sisal Fibers Reinforced Cement-Based Plates, Kaio Campos, Kíssila Goliath, L. Souza, F. Teixeira Sep 2025

Durability Of Sisal Fibers Reinforced Cement-Based Plates, Kaio Campos, Kíssila Goliath, L. Souza, F. Teixeira

C3 Symposium 2025

Sustainable materials have been gaining increasing attention in the construction sector due to their environmental advantages and the need for cost-effective solutions. An example of this is vegetable fibers, which are recognized as a sustainable and eco-friendly alternative for the reinforcement of cementitious composites in civil engineering applications. To contribute to our knowledge about the durability of these materials, this study investigated the mechanical behavior of cementitious plates reinforced with 5% long aligned sisal fibers materials after being subjected to accelerated aging. To improve the durability of the composite, 50% of the cement in matrix was replaced by 40% metakaolin …

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Viability Of Waste Glass Powder In Inter-Ground Alkali Activated Cement, Andrew Callender, Xander Babcock, Thien Tran, Maria Juenger Sep 2025

Viability Of Waste Glass Powder In Inter-Ground Alkali Activated Cement, Andrew Callender, Xander Babcock, Thien Tran, Maria Juenger

C3 Symposium 2025

No abstract provided.

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Recovery Of Silica As Scm From Olivine Using Oxalic Acid-Enabled Chemical Comminution, Jie Shi, Hongyan Ma Sep 2025

Recovery Of Silica As Scm From Olivine Using Oxalic Acid-Enabled Chemical Comminution, Jie Shi, Hongyan Ma

C3 Symposium 2025

Using supplementary cementitious materials (SCMs) to substitute cement or clinker, as a decarbonization strategy, is limited by the shortage of conventional SCMs like GGBS, fly ash, and silica fume. Meanwhile, mafic/ultramafic minerals are unlimited to be processed for SCMs production. In this study, oxalic acid is used to dissolve olivine ((Mg, Fe)2SiO4) to produce amorphous silica. Results show that high purity amorphous silica could be successfully obtained and the yield can be up to 93.42%. This process endows the extra value of olivine alongside being used for carbon storage.

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Oxcem: A Novel Carbon-Negative Cement Based On Oxalic Acid And Steel Slag, Xing Cheng, Jihui Qin, Hongyan Ma Sep 2025

Oxcem: A Novel Carbon-Negative Cement Based On Oxalic Acid And Steel Slag, Xing Cheng, Jihui Qin, Hongyan Ma

C3 Symposium 2025

The proper disposal of steel slag remains a challenging issue. This study explores a novel carbon-negative cement, utilizing the reaction between steel slag and oxalic acid. The mechanical properties, phase composition, and microstructure of OxCem were investigated through compressive strength tests, TG analysis, XRD, and MIP test. The results indicate that the optimal EAF/OA ratio is 3.5, achieving a 28-day compressive strength of 34.7 MPa. The strength enhancement of the paste is attributed to the influence of the reaction products, ferrous oxalate and calcium oxalate, on the pore structure.

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Transforming Agricultural Residues Into High-Performance Scms Through Mechanochemical Activation, Dia Brown, Juan Pablo Gevaudan Sep 2025

Transforming Agricultural Residues Into High-Performance Scms Through Mechanochemical Activation, Dia Brown, Juan Pablo Gevaudan

C3 Symposium 2025

Despite the abundance of ashed agricultural residues and their potential as supplementary cementitious materials (SCMs), given a high silica content (up to 90 wt.%), their high water demand limits their use. This challenge compromises both the fresh-state workability and mechanical performance of supplemented concrete – a pivotal challenge for countries in the Global South with large agricultural sectors and low production of other industrial SCMs. To address this limitation, we investigate two innovative mechanochemical methods and their effects on the fresh-state workability issues of these ash-based SCMs. This presentation will share our latest results describing how the mechanochemical activation of …

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Thermochemical Pre-Treatments On Corn Stover Ash To Boost Its Reactivity, P V P Moorthi, Zhihui Sun Sep 2025

Thermochemical Pre-Treatments On Corn Stover Ash To Boost Its Reactivity, P V P Moorthi, Zhihui Sun

C3 Symposium 2025

When treated properly, corn stover ash (CSA) is known to be an effective source of supplementary cementitious materials (SCM) for use in concrete. The influence of thermochemical pre-treatments on the reactivity of CSA was studied in this project. The result shows that acid pre-treatment was effective and necessary in the removal of organic and inorganic compounds from the corn stover. The pre-treatment conditions including type and concentration of acid used, temperature, pre-treatment duration, and the acid/ash (A/A) ratio are important factors that affect the reactivity of the final product. This study shows that a proper pre-treatment condition will lead to …

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Hydrophobic Modification For The Design Of High-Performance And Ultra-High Performance Cementitious Composites, Iman Aghayan, Scott Muzenski, Reed T. Heintzkill, Marina I. Kozhukhova, Habib Tabatabai, Konstantin Sobolev Sep 2025

Hydrophobic Modification For The Design Of High-Performance And Ultra-High Performance Cementitious Composites, Iman Aghayan, Scott Muzenski, Reed T. Heintzkill, Marina I. Kozhukhova, Habib Tabatabai, Konstantin Sobolev

C3 Symposium 2025

This paper presents a novel method for designing high-performance and ultra-high-performance concrete (HPC/UHPC) through hydrophobic and nanomaterial modification. Three-dimensional hydrophobization of cementitious matrices is achieved by incorporating water-based emulsions of silico-organic compounds containing active hydrogen. The approach enables high-strength matrices with superior flexural performance via fiber reinforcement, further improved by uniformly distributed small air voids that promote multi-cracking and strain-hardening behavior. Incorporating aluminum oxide (Al₂O₃) nanofibers with 1% silica fume (or metakaolin) produces UHPC-grade strength and ductility while reducing chemical shrinkage and simplifying composition. Developed with Type V and I cements at W/CM < 0.3, the composites reached compressive strengths up to 195 MPa, exhibited high flowability, and showed excellent strain-hardening when reinforced with 2% synthetic macrofibers (PVA and HDPE), with HDPE yielding greater ductility. This synergy of hydrophobic modification, nanoengineered matrix, and synthetic fibers offers a cost-effective, sustainable alternative to conventional HPC/UHPC, exceeding durability and environmental performance benchmarks.

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Multicomponent Portland Cement Composites Modified With Graphene Oxide: Hydration And Mechanical Properties, Małgorzata Safuta, Cataldo Valentini, Artur Ciesielski Sep 2025

Multicomponent Portland Cement Composites Modified With Graphene Oxide: Hydration And Mechanical Properties, Małgorzata Safuta, Cataldo Valentini, Artur Ciesielski

C3 Symposium 2025

We report here on the effect of the addition of graphene oxide on the basic properties of multicomponent Portland cements. Cement mortars incorporating two different dosages of graphene oxide (0.025 wt.% and 0.05 wt.%) were manufactured with the use of Portland cement containing limestone as well as cement containing granulated blast furnace slag, and, for comparison, ordinary Portland cement. We then further investigated the hydration heat by means of semi-adiabatic calorimetry, mechanical properties by means of flexural and compressive strength tests as well as comprehensive microstructural analysis of cement mortars at the age of 28 days, proving a considerable difference …

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Tailoring Ultra-High-Performance Concrete Toughness With Carbon Fibers: Linking Microstructure And Fracture Energy, J.D. Ríos, H. Cifuentes, G. Ruiz, D.C. González, M.A. Vicente, R.C. Yu, C. Leiva Sep 2025

Tailoring Ultra-High-Performance Concrete Toughness With Carbon Fibers: Linking Microstructure And Fracture Energy, J.D. Ríos, H. Cifuentes, G. Ruiz, D.C. González, M.A. Vicente, R.C. Yu, C. Leiva

C3 Symposium 2025

This paper presents a multiscale experimental study on the effect of carbon microfiber reinforcement on the fracture behavior of ultra-high-performance fiber-reinforced concrete (UHPFRC).Various fiber lengths (0.1–6 mm) and contents (1.2–20 kg/m³) were tested, linking microstructural features obtained via X-ray computed tomography (CT), mercury intrusion porosimetry (MIP), and scanning electron microscopy (SEM) to mechanical performance. Results show that a dosage of 6 kg/m³ of 3–6 mm fibers offers a balance between workability and fracture resistance, with fracture energy increasing up to 195% compared to plain concrete. This research provides insights for optimizing fiber type and content in UHPFRC for structural applications.

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Enhancing Optical Performance Of Cementitious Composites With Nano-Tio₂ Based Surface Treatment: A Cost-Effective Approach To Boost Solar Reflectance Index, Rui Bai, Marina Lopez-Arias, Mirian Velay-Lizancos Sep 2025

Enhancing Optical Performance Of Cementitious Composites With Nano-Tio₂ Based Surface Treatment: A Cost-Effective Approach To Boost Solar Reflectance Index, Rui Bai, Marina Lopez-Arias, Mirian Velay-Lizancos

C3 Symposium 2025

The Solar Reflectance Index (SRI) is a critical parameter for evaluating a material's ability to reflect solar radiation and release absorbed heat, affecting its surface temperature and thermal performance. Nano-titanium dioxide (NTiO₂) is widely used to enhance SRI in paints due to its high refractive index and light color; however, its high-cost limits large-scale intermixing applications for cementitious composites. This study investigates a cost-effective alternative by applying a NTiO₂-based cationic molecular emulsion as a surface treatment. Cement paste samples (5 × 5 × 1 cm for solar reflectance and 10 × 10 × 2 cm for emittance tests) were cast …

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Assessing The Synergistic Role Of Nanosilica In The Performance Of Concrete With Natural Pozzolans, Alberto Castillo, Mirian Velay-Lizancos, Jan Olek Sep 2025

Assessing The Synergistic Role Of Nanosilica In The Performance Of Concrete With Natural Pozzolans, Alberto Castillo, Mirian Velay-Lizancos, Jan Olek

C3 Symposium 2025

With the diminishing availability of traditional supplementary cementitious materials, alternative options such as natural pozzolans (NPs) are emerging as promising alternatives. While NPs can significantly enhance the durability of concrete, their use often results in reduced early-age strength. Existing technical literature shows that when used in concrete, nanosilica (nS) provides nucleation sites for deposition of the hydrates, thus accelerating the hydration process and enhancing early-age strength development. Consequently, combining nS with NPs offers a promising, yet largely unexplored, pathway toward more sustainable and practical solutions for concrete construction. This study evaluates the combined effects of using NPs and nS in …

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Functionalized Carbon Material In Cement-Based Composites, A Multivariate Approach, Luca Lavagna, Carlo Amata, Daniel Suarez-Riera, Matteo Pavese Sep 2025

Functionalized Carbon Material In Cement-Based Composites, A Multivariate Approach, Luca Lavagna, Carlo Amata, Daniel Suarez-Riera, Matteo Pavese

C3 Symposium 2025

This work describes the process that led to the optimization of compressive strength and fracture energy of a cement-based composite material enhanced with carbon allotropes: carbon nanotubes (CNTs), graphene nanoplatelets (GNPs), and carbon fibers (CFs). The goal was achieved through the use of a multivariate analysis system, modifying three variables corresponding to the quantities of CNTs, GNPs, and CFs. All the allotropes used in the study were subjected to functionalization to improve their wettability and interaction with the cement matrix. A face-centered central composite design (FCCD) was used as the experimental design, where these three variables were modified at three …

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Graphene Reinforced Cement-Based Triboelectric Nanogenerator For Efficient Energy Harvesting, Wenkui Dong, Wengui Li Sep 2025

Graphene Reinforced Cement-Based Triboelectric Nanogenerator For Efficient Energy Harvesting, Wenkui Dong, Wengui Li

C3 Symposium 2025

This study investigated a graphene reinforced cement-based triboelectric nanogenerator (TENG) aimed at harvesting mechanical energies in infrastructure. The triboelectric layers of the cement-based TENG consisted of a fully cured graphene modified cement-based plate and a polytetrafluoroethylene (PTFE) film, which were tested under a contact-separation mode. Microstructural analysis indicated that the graphene was well-dispersed in the cementitious matrix, and the graphene-cement composites achieved excellent compressive and flexural strengths of 53.0 and 3.5 MPa, respectively. The electrical characteristics of the graphene-cement composites, specifically their resistivity and impedance, showed that they did not reach the percolation threshold, making them ideal dielectric materials with …

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Additive Manufacturing Of Ultra-High-Performance Concrete: From Mechanical Characterization To Large-Scale Application, Raul Marrero-Rosa, Shady Gomaa, Elmer Irizarry, Hassan Ahmed, Ayesha Ahmed, Jiaqi Liu, Gianluca Cusatis Sep 2025

Additive Manufacturing Of Ultra-High-Performance Concrete: From Mechanical Characterization To Large-Scale Application, Raul Marrero-Rosa, Shady Gomaa, Elmer Irizarry, Hassan Ahmed, Ayesha Ahmed, Jiaqi Liu, Gianluca Cusatis

C3 Symposium 2025

In this work, extensive experimental investigations were conducted on 3D printable Ultra-High-Performance Concrete (UHPC) at multiple scales. Initially, nanomodification techniques were employed to transform the self-leveling nature of UHPC into a more viscous mix using nanomaterials such as nano clay, which showed no detrimental effects on the mechanical performance of cast samples tested under uniaxial compression, split tension, and notched three-point bending. The developed mix then underwent a comprehensive experimental program to evaluate its rheological performance and was subsequently tested using various 3D printing systems featuring different automation setups, extrusion mechanisms, pumps, and nozzle configurations. To assess mechanical performance without …

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Computational Simulations Fresh-To-Solid Transition For Additive Manufacturing Of Ultra-High-Performance Fiber Reinforced Concrete, Erol Lale, Bahar Ayhan, Ayesha Ahmed, Elmer Irizarry, Jiaqi Liu, Shady Gomaa, Raul Marrero-Rosa, Gianluca Cusatis Sep 2025

Computational Simulations Fresh-To-Solid Transition For Additive Manufacturing Of Ultra-High-Performance Fiber Reinforced Concrete, Erol Lale, Bahar Ayhan, Ayesha Ahmed, Elmer Irizarry, Jiaqi Liu, Shady Gomaa, Raul Marrero-Rosa, Gianluca Cusatis

C3 Symposium 2025

Additive manufacturing of concrete is a topic of interest within the academia and industry. Simulating the printable concrete behavior from the fresh state to hardened state to long-term will provide the future engineers the ability to optimize the design and predict failure of structural elements. A key aspect for concrete additive manufacturing is the complexity of optimization which includes systems, schedule, and materials. Our research focus on the simulation fresh state, hardened behavior, and the transition from fluid-to-solid of nanoclay modified ERDC ultra-high-performance fiber reinforced concrete system. Discrete fresh concrete model (DFC) and Smooth Particle Hydrodynamics (SPH) model are studied …

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Effect Of Chemical Additives On Performance Of Low-Clinker 3d Printing Mortar, Jingjie Wei, Kamal H. Khayat Sep 2025

Effect Of Chemical Additives On Performance Of Low-Clinker 3d Printing Mortar, Jingjie Wei, Kamal H. Khayat

C3 Symposium 2025

The study investigates the effect of three chemical accelerators, nano-C-S-H solution agent (NCSH), organic composite accelerator (OC), and an aluminum sulfate-based accelerator (FA), on the performance of low-clinker 3D printing mortar. The mixture with 80% clinker replacement, consisting of 20% cement, 40% limestone filler, and 40% slag was set. Using 2% OC significantly enhanced the compressive strength, increasing 3- and 28-day compressive strength by 47% and 18%, respectively, compared to ref. mixture. Adding 2% OC can accelerate setting time by 35%, compared to the ref mixture. The OC-type accelerator was recommended for low-clinker 3D printing mixture.

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Advancing Underwater Construction With 3d Printing: A Two-Stage Approach, Onur Ozturk, Caleb Lunsford, Sriramya Duddukuri Nair Sep 2025

Advancing Underwater Construction With 3d Printing: A Two-Stage Approach, Onur Ozturk, Caleb Lunsford, Sriramya Duddukuri Nair

C3 Symposium 2025

Underwater concreting presents a unique challenge, requiring advanced materials and construction methods to endure harsh submerged environments. Traditional techniques often encounter difficulties in adapting to the dynamic underwater conditions. In contrast, 3D concrete printing (3DCP) offers a revolutionary alternative, enabling automated, precise, and highly customizable fabrication of resilient underwater structures. This study introduces a two-stage cementitious 3D printing system that dynamically adjusts accelerator dosages at the nozzle, optimizing printability in submerged conditions. Evaluations in both air and underwater settings reveal that real-time dosage control effectively addresses critical challenges, overcoming the limitations of pre-mixed underwater admixtures (reduced flowability and compromised strength) …

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Magnetic Technologies For A Carbon Conscious Concrete, Sriramya Duddukuri Nair, Onur Ozturk Sep 2025

Magnetic Technologies For A Carbon Conscious Concrete, Sriramya Duddukuri Nair, Onur Ozturk

C3 Symposium 2025

Concrete has long been a cornerstone of civil infrastructure due to its strength, versatility, and cost-effectiveness. However, as global construction demands increase, so do concerns about the environmental impact of concrete production, particularly its significant carbon footprint. In recent years, numerous advanced materials and innovative methods have been explored to enhance concrete performance while minimizing its ecological impact. These advancements include the incorporation of alternative cementitious materials, self-healing agents, and 3D printing technologies. Among the emerging techniques, the use of magnetic fields to improve concrete properties has garnered considerable attention, as evidenced by the growing body of research over the …

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Effect Of Absorption Kinetics Of Superabsorbent Polymer On 3d Printing Characteristics, Yucun Gu, Seongho Han, Kamal H. Khayat Sep 2025

Effect Of Absorption Kinetics Of Superabsorbent Polymer On 3d Printing Characteristics, Yucun Gu, Seongho Han, Kamal H. Khayat

C3 Symposium 2025

This study evaluates the effect of different superabsorbent polymers (SAP) types on rheological properties, printability, and mechanical properties of 3D concrete printing (3DCP). Three types of SAP, including two acrylamide-co-acrylic polymers with coarse and fine particle sizes (S1 and S2) and an acrylic copolymer (S3), were employed. Results showed that the use of S1 and S2 SAP exhibiting high retention ability enhanced thixotropy, whereas the S3 SAP with rapid desorption reduced thixotropy. The S1 SAP was the most significant in maintaining a higher internal relative humidity, thus resulting in higher 28-d compressive strength. The reduction in 28-day compressive strength for …

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Mechanics Of Fracture In Layered Architected Materials, Reza Moini, Aimane Najmeddine, Shashank Gupta Sep 2025

Mechanics Of Fracture In Layered Architected Materials, Reza Moini, Aimane Najmeddine, Shashank Gupta

C3 Symposium 2025

This talk asks the role of mechanics of materials, particularly fracture mechanics in design and engineering civil infrastructure materials. Concrete, a quasi-brittle material is the backbone of the civil infrastructure. Decades of research on engineering and fracture mechanics of concrete led by the hundreds of pioneering works of great scholars, have helped us understand mechanism of crack initiation and propagation in heterogeneous materials. However, there remain a significant need to continue understand mechanics of damage in conventional and novel heterogeneous infrastructure materials. Growth in automation and robotics (e.g., 3D-printing), innovative cementitious composite materials (e.g., architected material), and numerical frameworks (e.g., …

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Performance-Based Design Of 3d Printable Cement Composite Using Locally Available Materials, Haodao Li, Kamal H. Khayat Sep 2025

Performance-Based Design Of 3d Printable Cement Composite Using Locally Available Materials, Haodao Li, Kamal H. Khayat

C3 Symposium 2025

Proportioning 3D printable materials using locally available resources offers significant environmental and economic benefits while supporting local communities. This study proposes a performance-based design approach to adapt these materials into printable mixtures, focusing on key fresh and hardened properties. Binder combinations made with locally available materials were initially optimized for enhanced packing density and flow characteristics. Optimized candidates were narrowed down using a radar chart method based on multivariate criteria closely linked to printing performance.The printability of the optimized cement composites was subsequently validated. Developing such print materials enhances the cost-effectiveness of 3D printing in construction and expands its applicability …

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Developing 3d Printable Concrete Using Quarry By-Products As Partial Replacement For Cement, Tippabhotla A. Kamakshi, Bao Chau, Aidyn Tugelbayev, Andrew P. Mccoy, Alexander S. Brand Sep 2025

Developing 3d Printable Concrete Using Quarry By-Products As Partial Replacement For Cement, Tippabhotla A. Kamakshi, Bao Chau, Aidyn Tugelbayev, Andrew P. Mccoy, Alexander S. Brand

C3 Symposium 2025

3D concrete printing (3DCP) is rapidly growing due to its wide range of advantages over conventional cast concrete. However, one major concern is that it 3DCP mixes typically have high cement contents and have a high carbon footprint as a result. To address this concern, this study incorporates quarry by-products (e.g., pond fines, screenings) in 3DCP mixes, which serves as a rheology modifier and serves to reduce the cement content. Pond fines were used as a partial replacement of cement, and screenings were used as the fine aggregate. The resultant mixtures demonstrated adequate compressive strength, higher compressive strength, and improved …

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Green 3d Printing Concrete Containing Biochar And Waste Wind Turbine Blade Powder, Ping Lyu, Kejin Wang, Shelby Doyle, Simon Laflamme, Sri Sritharan Sep 2025

Green 3d Printing Concrete Containing Biochar And Waste Wind Turbine Blade Powder, Ping Lyu, Kejin Wang, Shelby Doyle, Simon Laflamme, Sri Sritharan

C3 Symposium 2025

Three green three-dimension printing concrete (3DPC) mixtures were made with biochar (BC), waste wind turbine blade powder (WTBP), and a pre-packaged 3DPC material (Sika-752). The mixtures were used to print small and larger beams with various fill patterns/rates. The results indicate that use of 3%BC (wetted with mixing water) and10% WTBP improved fluidity, especially slump, of the 3DPC mixture. 3%BC slightly reduced strength and ductility of the 3DPC. 10% WTBP decreased strength but increased ductility of the printed specimens. Optimized infill can improve load capacity. The use of BC and WTBP in 3DPC has promising potential in construction engineering applications.

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Enhanced Shape Stability Of Flowable Mortar Through Co2 Injection For 3d Concrete Printing Application, Seongho Han, Alfred Addai-Nimoh, Yucun Gu, Kamal H. Khayat Sep 2025

Enhanced Shape Stability Of Flowable Mortar Through Co2 Injection For 3d Concrete Printing Application, Seongho Han, Alfred Addai-Nimoh, Yucun Gu, Kamal H. Khayat

C3 Symposium 2025

This study explores the direct injection of CO2 into the 3D printer head during the printing process, enabling real-time control of yield stress evolution in flowable mixtures. CO2 concentrations ranging from 0.5% to 1.4% by cement weight were tested by varying injection times. CO2 injection reduced slump flow of mortar from 250 to 100 mm, as reflected in the decreased width and increased height of printed layers. Mortar with 0.5% CO2 maintained flowability but experienced shape collapse during layer stacking, while higher CO2 concentrations led to nozzle blockages.

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