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Seeding Effects Of Submicron Caal-No3 Ldh Particles On The Hydration And Properties Of Portland Cement And Sulfoaluminate Cement Pastes, Sukanta K. Mondal, Monday Uchenna Okoronkwo Apr 2024

Seeding Effects Of Submicron Caal-No3 Ldh Particles On The Hydration And Properties Of Portland Cement And Sulfoaluminate Cement Pastes, Sukanta K. Mondal, Monday Uchenna Okoronkwo

Chemical and Biochemical Engineering Faculty Research & Creative Works

Layered Double Hydroxide (LDH) Is Reported To Improve The Durability Of Concretes, Primarily Due To Its Ability To Exchange Anionic Species, Including Chloride, Which Is Implicated In Corrosion-Driven Durability Issues. However, There Is No Comprehensive Study Investigating The Effect Of LDH On The Properties Of Different Cement Systems At Both Early And Mature Ages. In This Study, The Early Age And Mature Age Properties Of Portland Cement (OPC) And Calcium Sulfoaluminate (CSA) Cement Pastes Seeded With Submicron-Sized Calcium Aluminum-NO3 LDH (CaAl-NO3 LDH) Were Investigated. The Effects Of The 1–5%mass Dosage Of LDH On The Hydration Of Both Cement Systems Were …


Fly Ash Coated With Alumina Sol For Improving Strength And Thermal Insulation Of Mullite Porous Ceramics, Minghui Li, Peilin Li, Qingqing Gao, Saisai Li, Ruoyu Chen, Haiming Wen, Canhua Li Feb 2024

Fly Ash Coated With Alumina Sol For Improving Strength And Thermal Insulation Of Mullite Porous Ceramics, Minghui Li, Peilin Li, Qingqing Gao, Saisai Li, Ruoyu Chen, Haiming Wen, Canhua Li

Materials Science and Engineering Faculty Research & Creative Works

The manufacturing of mullite porous ceramics with high strength and low thermal conductivity was achieved through foam gel-casting processes using fly ash coated with alumina sol layers. This research aimed to investigate the effect of alumina sol concentration on foaming slurry rheology, as well as the influence of alumina sol coating layers on the microstructure, phase compositions and properties of the resulting mullite porous ceramics. Increasing the alumina sol concentration from 5 to 20 wt% improved both the viscosity and thixotropy of the foaming slurries while enhanced the shear thinning behavior. Porous ceramics prepared with fly ash coated with alumina …


Additive Manufacturing Of Novel Lightweight Insulation Refractory With Hierarchical Pore Structures By Direct Ink Writing, Saisai Li, Jiaxuan Xin, Ruoyu Chen, Haiming Wen Jan 2024

Additive Manufacturing Of Novel Lightweight Insulation Refractory With Hierarchical Pore Structures By Direct Ink Writing, Saisai Li, Jiaxuan Xin, Ruoyu Chen, Haiming Wen

Materials Science and Engineering Faculty Research & Creative Works

A direct ink writing process using fly ash foaming slurries was employed for the additive manufacturing of lightweight mullite insulation refractory with hierarchical pore structures. The viscosity, thixotropy, and shear thinning behavior of the inks were analyzed to investigate the effect of the inorganic binder and dispersant of the foaming inks. A slurry exhibiting excellent rheological characteristics was identified, consisting of 45 wt% fly ash floating beads, 55 wt% water, 3.0 wt% additional dispersant, and 6.0 wt% additional binder. Furthermore, through the optimization of printing parameters such as printing pressure and printing speed, notable enhancements were achieved in the pore …


The Comprehensive Study Of High Viscosity Friction Reducers In High-Tds And High-Temperature Environments, Xiaojing Ge Jan 2024

The Comprehensive Study Of High Viscosity Friction Reducers In High-Tds And High-Temperature Environments, Xiaojing Ge

Doctoral Dissertations

"High viscosity friction reducers (HVFRs) have been recently gaining more attention and increasing in use, not only as friction-reducing agents but also as proppant carriers. Reusing of produced water has also been driven by both environmental and economic benefits. Currently, most friction reducers on the market are anionic friction reducers, which are fully compatible with most produced water with low to medium level of Total Dissolved Solids (TDS) but show a significant drop at high TDS conditions in term of their friction reduction performance in most cases. On the contrary, cationic friction reducers are believed to have better TDS tolerance …


Viscoelastic Properties Of Fresh Cement Paste: Measuring Procedures And Influencing Parameters, Ammar Yahia, Arnaud Perrot, Dimitri Feys, Kamal Khayat, Mohammed Sonebi, Shiho Kawashima, Wolfram Schmidt Jul 2023

Viscoelastic Properties Of Fresh Cement Paste: Measuring Procedures And Influencing Parameters, Ammar Yahia, Arnaud Perrot, Dimitri Feys, Kamal Khayat, Mohammed Sonebi, Shiho Kawashima, Wolfram Schmidt

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Fresh cement pastes behave as viscoelastic materials below the flow onset. The measurements of viscoelastic properties of fresh cement paste provide valuable insight into the dispersion of solid particles as well as the hydration kinetics at early age and its influence on the structural evolution and solidification behavior at quasi-static conditions. Monitoring the development of viscoelastic properties of fresh cement paste using dynamic oscillatory shear measurements can also elucidate the working mechanisms of chemical admixtures. These properties are efficient indicators to guide mixture proportion design and are necessary to understand the rheology and stability of concrete. In this paper, the …


Rilem Tc 266-Mrp: Round-Robin Rheological Tests On High Performance Mortar And Concrete With Adapted Rheology—A Comprehensive Flow Curve Analysis, Dimitri Feys, Helena Keller, Khadija El Cheikh, Egor Secrieru, Yannick Vanhove Jun 2023

Rilem Tc 266-Mrp: Round-Robin Rheological Tests On High Performance Mortar And Concrete With Adapted Rheology—A Comprehensive Flow Curve Analysis, Dimitri Feys, Helena Keller, Khadija El Cheikh, Egor Secrieru, Yannick Vanhove

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

A comprehensive testing program was carried out to compare the rheological properties of flowable concrete that can be obtained from different rheometers. The results obtained from seven rheometers using vane or similar geometries are discussed. A comprehensive flow curve analysis is undertaken for further comparison of the various rheometers. Partially, large differences could be observed between the results obtained from the different rheometers. However, the device-specific trendlines are shown to have significant correlations with the overall baseline. Two potential causes of differences between results are highlighted: imposition/registration of torque/rotational velocity and discrepancies between the measured material flow behavior in the …


Particle Migration In Large Cross-Section Ceramic On-Demand Extrusion Components, Austin J. Martin, Wenbin Li, Jeremy Lee Watts, Gregory E. Hilmas, Ming-Chuan Leu, Tieshu Huang Mar 2023

Particle Migration In Large Cross-Section Ceramic On-Demand Extrusion Components, Austin J. Martin, Wenbin Li, Jeremy Lee Watts, Gregory E. Hilmas, Ming-Chuan Leu, Tieshu Huang

Materials Science and Engineering Faculty Research & Creative Works

Ceramic On-Demand Extrusion (CODE) is a direct ink writing process which allows for the creation of near theoretically dense ceramic components with large cross-sections due to oil-assisted drying. Yttria-stabilized zirconia (YSZ) colloidal pastes (∼d50 ≲ 1 µm) were used in CODE to produce dense (multi-road infill and ≳ 98% relative density), large continuous volume (> 1 cm3), and high fidelity (nozzle diameters ≲ 1 mm) structural ceramic components. However, many of these printed components underwent significant particle migration after forming. The reason for this particle migration defect was investigated using the coffee-ring effect for dilute solutions and rheological methods for …


Particle Migration In Large Cross-Section Ceramic On-Demand Extrusion Components, Austin J. Martin, Wenbin Li, Jeremy Lee Watts, Gregory E. Hilmas, Ming-Chuan Leu, Tieshu Huang Mar 2023

Particle Migration In Large Cross-Section Ceramic On-Demand Extrusion Components, Austin J. Martin, Wenbin Li, Jeremy Lee Watts, Gregory E. Hilmas, Ming-Chuan Leu, Tieshu Huang

Mathematics and Statistics Faculty Research & Creative Works

Ceramic On-Demand Extrusion (CODE) is a direct ink writing process which allows for the creation of near theoretically dense ceramic components with large cross-sections due to oil-assisted drying. Yttria-stabilized zirconia (YSZ) colloidal pastes (∼d50 ≲ 1 µm) were used in CODE to produce dense (multi-road infill and ≳ 98% relative density), large continuous volume (> 1 cm3), and high fidelity (nozzle diameters ≲ 1 mm) structural ceramic components. However, many of these printed components underwent significant particle migration after forming. The reason for this particle migration defect was investigated using the coffee-ring effect for dilute solutions and rheological methods for …


Particle Migration In Large Cross-Section Ceramic On-Demand Extrusion Components, Austin J. Martin, Wenbin Li, Jeremy Lee Watts, Gregory E. Hilmas, Ming-Chuan Leu, Tieshu Huang Mar 2023

Particle Migration In Large Cross-Section Ceramic On-Demand Extrusion Components, Austin J. Martin, Wenbin Li, Jeremy Lee Watts, Gregory E. Hilmas, Ming-Chuan Leu, Tieshu Huang

Materials Science and Engineering Faculty Research & Creative Works

Ceramic On-Demand Extrusion (CODE) is a direct ink writing process which allows for the creation of near theoretically dense ceramic components with large cross-sections due to oil-assisted drying. Yttria-stabilized zirconia (YSZ) colloidal pastes (∼d50 ≲ 1 µm) were used in CODE to produce dense (multi-road infill and ≳ 98% relative density), large continuous volume (> 1 cm3), and high fidelity (nozzle diameters ≲ 1 mm) structural ceramic components. However, many of these printed components underwent significant particle migration after forming. The reason for this particle migration defect was investigated using the coffee-ring effect for dilute solutions and rheological methods for …


Rheological Characterization Of Ultra-High Performance Concrete For 3d Printing, Arun R. Arunothayan, Behzad Nematollahi, Kamal Khayat, Akilesh Ramesh, Jay G. Sanjayan Feb 2023

Rheological Characterization Of Ultra-High Performance Concrete For 3d Printing, Arun R. Arunothayan, Behzad Nematollahi, Kamal Khayat, Akilesh Ramesh, Jay G. Sanjayan

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The authors recently developed a 3D-printable ultra-high performance fiber-reinforced concrete (3DP-UHPFRC) for additive construction of structural members with significantly reduced reliance on steel bars. This study investigates the rheological behavior of the developed 3DP-UHPFRC. The effects of two major factors affecting the performance of 3DP-UHPFRC, namely steel fiber volume (0, 1%, and 2%) and nano-clay (NC) content (0, 0.1%, and 0.2% by binder mass) on workability, static yield stress, dynamic yield stress, and apparent viscosity were determined. Test results showed that the inclusion of steel fibers and NC reduced the workability and led to a significant increase in the static …


Homogeneous Flow Performance Of Steel-Fiber Reinforced Self-Consolidating Concrete For Repair Application: A Biphasic Approach, Naimeh Nouri, Masoud Hosseinpoor, Ammar Yahia, Kamal Khayat Feb 2023

Homogeneous Flow Performance Of Steel-Fiber Reinforced Self-Consolidating Concrete For Repair Application: A Biphasic Approach, Naimeh Nouri, Masoud Hosseinpoor, Ammar Yahia, Kamal Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In this study, fiber-reinforced self-consolidating concrete (FR-SCC) was considered as a diphasic suspension of fiber and coarse aggregate (F-A ≥ 5 mm) skeleton in mortar suspension with solid particles finer than 5 mm. The coupled effect of the volumetric content of fibers, coarse aggregate particle-size distribution, and rheological properties of the mortar on the passing ability and dynamic stability of various FR-SCC mixtures was investigated. Nine high-strength and 10 conventional-strength FR-SCC mixtures for repair application were proportioned with water-to-binder ratios (W/B) of 0.35 and 0.42, respectively, and macro steel fibers of 0.1%–0.5% volumetric contents. The dosages of high-range water-reducer (HRWR) …


Effect Of Class C And Class F Fly Ash On Early-Age And Mature-Age Properties Of Calcium Sulfoaluminate Cement Paste, Sukanta K. Mondal, Carrie Clinton, Hongyan Ma, Aditya Kumar, Monday Uchenna Okoronkwo Feb 2023

Effect Of Class C And Class F Fly Ash On Early-Age And Mature-Age Properties Of Calcium Sulfoaluminate Cement Paste, Sukanta K. Mondal, Carrie Clinton, Hongyan Ma, Aditya Kumar, Monday Uchenna Okoronkwo

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

To Promote the Sustainable Development of Eco-Efficient Calcium Sulfoaluminate (CSA) Cements through the Partial Replacement of the CSA Clinker with Supplementary Cementitious Waste Products, the Effects of Coal Fly Ashes on the Early-Age and Mature-Age Properties of a Calcium Sulfoaluminate (CSA)-Based Cement Paste Were Investigated. the Impacts of Both Class C and Class F Fly Ashes on the Rheological Properties, Hydration Kinetics, and Compressive Strength Development of CSA Cement Paste Were Studied. Rheology-Based Workability Parameters, Representing the Rate of Loss of Flowability, the Rate of Hardening, and the Placement Limit, Were Characterized for the Pastes Prepared with Fixed Water-To-Cement (W/c) …


Improving Strength And Microstructure Of Sic Reticulated Porous Ceramic Through In-Situ Generation Of Sic Whiskers Within Hollow Voids, Ruoyu Chen, Kunshi Xie, Haipeng Zhu, Qun He, Saisai Li, Haiming Wen Jan 2023

Improving Strength And Microstructure Of Sic Reticulated Porous Ceramic Through In-Situ Generation Of Sic Whiskers Within Hollow Voids, Ruoyu Chen, Kunshi Xie, Haipeng Zhu, Qun He, Saisai Li, Haiming Wen

Materials Science and Engineering Faculty Research & Creative Works

SiC Reticulated Porous Ceramic with Excellent Strength and High-Density Ceramic Struts Was Successfully Prepared using the Polymer Replica Method, Followed by Pressureless Sintering under a Buried Charcoal Atmosphere. First, a Polyurethane (PU) Template Was Coated with a Si Slurry and Then a SiC-Containing Slurry, and Subsequently Heated under the Buried Charcoal Atmosphere. to Ensure Excellent Coating Ability of the Slurries, the Viscosity, Thixotropy, and Yield Stresses of the Si Slurry Were Optimized by Adjusting the Content of the Thickening Agent. during Heating, Si in the Coating Layer Reacted with the Residual C and CO Gas from the PU Template and …


Additive Manufacturing Of Sic-Sialon Refractory With Excellent Properties By Direct Ink Writing, Ruoyu Chen, Saisai Li, Xinxin Jin, Haiming Wen Jan 2023

Additive Manufacturing Of Sic-Sialon Refractory With Excellent Properties By Direct Ink Writing, Ruoyu Chen, Saisai Li, Xinxin Jin, Haiming Wen

Materials Science and Engineering Faculty Research & Creative Works

Additive manufacturing of SiC-Sialon refractory with complex geometries was achieved using direct ink writing processes, followed by pressure less sintering under nitrogen. The effects of particle size of SiC powders, solid content of slurries and additives on the rheology, thixotropy and viscoelasticity of ceramic slurries were investigated. The optimal slurry with a high solid content was composed of 81 wt% SiC (3.5 µm+0.65 µm), Al2O3 and SiO2 powders, 0.2 wt% dispersant, and 2.8 wt% binder. Furthermore, the accuracy of the structure of specimens was improved via adjustment of the printing parameters, including nozzle size, extrusion pressure, and layer height. The …


Additive Manufacturing Of (Mgconicuzn)O High-Entropy Oxide Using A 3d Extrusion Technique And Oxide Precursors, Ruoyu Chen, Saisai Li, Qingfeng Yan, Haiming Wen Jan 2023

Additive Manufacturing Of (Mgconicuzn)O High-Entropy Oxide Using A 3d Extrusion Technique And Oxide Precursors, Ruoyu Chen, Saisai Li, Qingfeng Yan, Haiming Wen

Materials Science and Engineering Faculty Research & Creative Works

This report presents an additive manufacturing approach, for the first time, to producing high-entropy oxides (HEOs) using a 3D extrusion-based technique with oxide precursors. The precursors were prepared by a wet chemical method from sulfates. Additives were utilized to optimize the rheological properties of the printing inks with these precursors, and the properties of the printed HEOs were improved by increasing the solid content of the inks. When ink with a solid content of 78 wt% was used for printing, the resulting HEO exhibited a relative density of 92% and a high dielectric constant after undergoing pressure less sintering at …


Synergistic Effect Of Shrinkage Mitigating Materials On Rheological Properties Of Flowable And Thixotropic Cement Paste, Kamran Aghaee, Ricarda Sposito, Kamal Khayat Oct 2022

Synergistic Effect Of Shrinkage Mitigating Materials On Rheological Properties Of Flowable And Thixotropic Cement Paste, Kamran Aghaee, Ricarda Sposito, Kamal Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study investigates the effect of individual and combined additions of CaO-based expansive agent (EA), shrinkage reducing admixture (SRA), and super absorbent polymer (SAP) on key characteristics of flowable cement paste mixtures proportioned with a water-to-cement ratio of 0.40. Of special interest is the effectiveness of these admixtures to mitigate shrinkage of cementitious materials for 3D printing. Static and dynamic yield stress, plastic and apparent viscosities, and thixotropy were evaluated at 20-min intervals up to 90 min. Compressive strength development and autogenous shrinkage were also determined. A factorial design approach was developed to evaluate the synergetic effects of the shrinkage …


Homogenous Flow Performance Of Steel Fiber-Reinforced Self-Consolidating Concrete For Repair Applications: Developing A New Empirical Set-Up, Naimeh Nouri, Masoud Hosseinpoor, Ammar Yahia, Kamal Khayat Oct 2022

Homogenous Flow Performance Of Steel Fiber-Reinforced Self-Consolidating Concrete For Repair Applications: Developing A New Empirical Set-Up, Naimeh Nouri, Masoud Hosseinpoor, Ammar Yahia, Kamal Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In this study, a new empirical Square-Box test was employed to evaluate the homogeneous flow performance of fiber-reinforced self-consolidating concrete (FR-SCC) under confined-flow conditions that are typical of repair applications. The Square-Box set-up consisted of a closed-circuit box, providing 2.4-m flow distance and a closed-surface cross section of 100-mm width and 200-mm height, equipped with 0 and 4 rows of reinforcing bar grids with 45-mm clear spacing. The flow performance was assessed in terms of dynamic stability and passing ability. The investigated mixtures were considered as diphasic suspensions of fiber-coarse aggregate (F-A > 5 mm) in suspending mortars containing particles finer …


Quantifying The Workability Of Calcium Sulfoaluminate Cement Paste Using Time-Dependent Rheology, Sukanta K. Mondal, Adam Welz, Carrie Clinton, Kamal Khayat, Aditya Kumar, Monday Uchenna Okoronkwo Aug 2022

Quantifying The Workability Of Calcium Sulfoaluminate Cement Paste Using Time-Dependent Rheology, Sukanta K. Mondal, Adam Welz, Carrie Clinton, Kamal Khayat, Aditya Kumar, Monday Uchenna Okoronkwo

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Poor workability is a common feature of calcium sulfoaluminate (CSA) cement paste. Multiple chemical admixtures, such as set retarders and dispersants, are frequently employed to improve the workability and delay the setting of CSA cement paste. A quantitative assessment of the compatibility, efficiency, and the effects of the admixtures on cement paste workability is critical for the design of an appropriate paste formulation and admixture proportioning. Very limited studies are available on the quantitative rheology-based method for evaluating the workability of calcium sulfoaluminate cement pastes. This study presents a novel and robust time-dependent rheological method for quantifying the workability of …


The Effect Of Sodium Polymethacrylate On The Rheology Of The Positive Paste And Performance Of The Lead-Acid Battery, Julian Kosacki, Dimitri Feys, Fatih Dogan Jul 2022

The Effect Of Sodium Polymethacrylate On The Rheology Of The Positive Paste And Performance Of The Lead-Acid Battery, Julian Kosacki, Dimitri Feys, Fatih Dogan

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Due to its rheological properties, positive lead-acid battery paste can be difficult to spread on lead current collectors accurately and efficiently under industry machinery and setting. Sodium polymethacrylate dispersant was studied as an effective positive paste additive that could lower the yield stress of the paste without affecting paste density and battery performance. Under a four-blade vane rheometer setup, stress growth and oscillatory amplitude strain sweep experiments evaluated the rheological properties of positive paste with the addition of varying amounts of sodium polymethacrylate. Further, the electrochemical effects of sodium polymethacrylate were also evaluated in 2V batteries by testing positive active …


A Novel Numerical Model Of Gelant Inaccessible Pore Volume For In Situ Gel Treatment, Jianqiao Leng, Xindi Sun, Mingzhen Wei, Baojun Bai Jun 2022

A Novel Numerical Model Of Gelant Inaccessible Pore Volume For In Situ Gel Treatment, Jianqiao Leng, Xindi Sun, Mingzhen Wei, Baojun Bai

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Inaccessible pore volume (IAPV) can have an important impact on the placement of gelant during in situ gel treatment for conformance control. Previously, IAPV was considered to be a constant factor in simulators, yet it lacked dynamic characterization. This paper proposes a numerical simulation model of IAPV. The model was derived based on the theoretical hydrodynamic model of gelant molecules. The model considers both static features, such as gelant and formation properties, and dynamic features, such as gelant rheology and retention. To validate our model, we collected IAPV from 64 experiments and the results showed that our model fit moderately …


A Novel Numerical Model Of Gelant Inaccessible Pore Volume For In Situ Gel Treatment, Jianqiao Leng, Xindi Sun, Mingzhen Wei, Baojun Bai Jun 2022

A Novel Numerical Model Of Gelant Inaccessible Pore Volume For In Situ Gel Treatment, Jianqiao Leng, Xindi Sun, Mingzhen Wei, Baojun Bai

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Inaccessible pore volume (IAPV) can have an important impact on the placement of gelant during in situ gel treatment for conformance control. Previously, IAPV was considered to be a constant factor in simulators, yet it lacked dynamic characterization. This paper proposes a numerical simulation model of IAPV. The model was derived based on the theoretical hydrodynamic model of gelant molecules. The model considers both static features, such as gelant and formation properties, and dynamic features, such as gelant rheology and retention. To validate our model, we collected IAPV from 64 experiments and the results showed that our model fit moderately …


Pumping Of Concrete: Understanding A Common Placement Method With Lots Of Challenges, Dimitri Feys, Geert De Schutter, Shirin Fataei, Nicos S. Martys, Viktor Mechtcherine Apr 2022

Pumping Of Concrete: Understanding A Common Placement Method With Lots Of Challenges, Dimitri Feys, Geert De Schutter, Shirin Fataei, Nicos S. Martys, Viktor Mechtcherine

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Several million cubic meters of concrete are pumped daily, as this technique permits fast concrete placement. Fundamental research has been performed and practical guidelines have been developed to increase the knowledge of concrete behavior in pipes. However, the pumping process and concrete behavior are not fully understood. This paper gives an overview of the current knowledge of concrete pumping. At first, the known physics governing the flow of concrete in pipes are introduced. A series of experimental techniques characterizing concrete flow behavior near a smooth wall to predict pressure-flow rate relationships are discussed, followed by recent developments in the use …


Novel Tri-Viscous Model To Simulate Pumping Of Flowable Concrete Through Characterization Of Lubrication Layer And Plug Zones, Tooran Tavangar, Masoud Hosseinpoor, Ammar Yahia, Kamal Khayat Feb 2022

Novel Tri-Viscous Model To Simulate Pumping Of Flowable Concrete Through Characterization Of Lubrication Layer And Plug Zones, Tooran Tavangar, Masoud Hosseinpoor, Ammar Yahia, Kamal Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In this study, computational fluid dynamics (CFD) was employed to simulate the pipe flow of 18 self-consolidating and four highly workable concrete mixtures in a 30-m long pumping circuit. Pressure loss (ΔP) in 100- and 125-mm diameter (DP) pipelines was measured under low (1.2–6.2 l/s) and high (8.1–16.4 l/s) flow rates (Q). The numerical simulation was successfully carried out using a two-fluid model and a new variable-viscosity single-fluid approach, namely double-Bingham and tri-viscous models, respectively. The radial variation of rheological properties of the concrete across the pipe section, representing the plug flow, sheared concrete, and lubrication layer (LL) zones was …


Viscosity Modifying Agents: Key Components Of Advanced Cement-Based Materials With Adapted Rheology, Hela Bessaies-Bey, Kamal Khayat, Marta Palacios, Wolfram Schmidt, Nicolas Roussel Feb 2022

Viscosity Modifying Agents: Key Components Of Advanced Cement-Based Materials With Adapted Rheology, Hela Bessaies-Bey, Kamal Khayat, Marta Palacios, Wolfram Schmidt, Nicolas Roussel

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Viscosity modifying agents (VMAs) are essential ingredients for the production of flowable cement-based materials. This paper presents an overview of commonly used VMAs and attempts to shed some light on the underlying physics at the origin of their mechanisms of action. The main molecular parameters of VMA controlling the rheological properties of the cement pore solution are highlighted. As the mechanisms of action of VMAs in cement-based materials are closely related to their affinity with the surface of cement particles, the adsorption of the main VMA types is discussed. The effect of VMAs on flow properties and stability of cement-based …


Strategies To Improve Shrinkage Resistance Of Cement-Based Materials For Extrusion-Based 3d Printing, Kavya Vallurupalli Jan 2022

Strategies To Improve Shrinkage Resistance Of Cement-Based Materials For Extrusion-Based 3d Printing, Kavya Vallurupalli

Doctoral Dissertations

"The main objective of this study is to develop new generation of shrinkage-resistant 3D printable mortar mixtures. To this end, the research work was carried out to: i) identify key material and processing parameters that affect printability; ii) investigate the influence of water-to-cement ratio, superplasticizer dosage, and welan gum content on mortar printability; iii) propose a “printability window” where rheological properties and desorptivity can secure successful printing; iv) investigate effect of shrinkage mitigation materials (expansive agent (EA), pre-saturated lightweight sand (LWS), superabsorbent polymers (SAP), and shrinkage reducing admixture) on printability and shrinkage performance of mortar; and v) evaluate the effect …


Design And Performance Of Self-Consolidating And Thixotropic Ultra-High-Performance Concrete For Infrastructure Construction And Rehabilitation, Le Teng Jan 2022

Design And Performance Of Self-Consolidating And Thixotropic Ultra-High-Performance Concrete For Infrastructure Construction And Rehabilitation, Le Teng

Doctoral Dissertations

"The objective of this research is to develop two classes of ultra-high-performance concrete (UHPC), one with self-consolidating consistency and the other with improved thixotropy. Tailoring the rheological properties of low yield stress UHPC can improve dispersion and orientation of steel fibers used in the design of UHPC, hence enhancing the tensile and flexural properties. Similarly, improving the thixotropy of UHPC can enable unique performance for the design of thin bonded bridge deck overlay. The research investigated various thixotropy enhancing admixtures to enhance the structural build-up at rest of UHPC. A total of 16 bonded overlay slab specimens were used to …


Sealant Injectivity Through Void Space Conduits To Assess Remediation Of Well Cement Failure, Mohammed Alkhamis, Abdulmohsin Imqam Jun 2021

Sealant Injectivity Through Void Space Conduits To Assess Remediation Of Well Cement Failure, Mohammed Alkhamis, Abdulmohsin Imqam

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The primary cement of oil and gas wells is prone to fail under downhole conditions. Thus, a remedial operation must be conducted to restore the wellbore integrity and provides zonal isolation. Many types of materials are currently used and/or have the potential to be employed in wellbore integrity applications, including, but not limited to, conventional Portland cement, microfine and ultrafine cement, thermoset materials, and thermoplastic materials. In this study, several types of materials were selected for evaluation: (1) conventional Portland cement, which is the most widely used in remedial operations in the petroleum industry, (2) polymer resin, which is one …


Evaluation Of Anti-Aging Performance Of Biochar Modified Asphalt Binder, Wenhao Dong, Feng Ma, Chen Li, Zhen Fu, Yue Huang, Jenny Liu Nov 2020

Evaluation Of Anti-Aging Performance Of Biochar Modified Asphalt Binder, Wenhao Dong, Feng Ma, Chen Li, Zhen Fu, Yue Huang, Jenny Liu

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

As a renewable biomass resource, biochar is new to modify or replace asphalt binder in pavement engineering. This paper focuses on the effect of biochar on the anti-aging performance of asphalt binder. The short-and long-term aging properties of biochar modified asphalt binder were investigated using dynamic shear rheometer (DSR) and bending beam rheometer (BBR) tests. The modification mechanism was investigated through the Fourier-transform infrared spectroscopy (FTIR) test. The aging tests and viscosity analysis showed that the softening point of biochar modified asphalt binder was higher than base asphalt binder, while the aging index and aging viscosity ratio were lower than …


Estimation Of Lubrication Layer Thickness And Composition Through Reverse Engineering Of Interface Rheometry Tests, Alexis Salinas, Dimitri Feys Apr 2020

Estimation Of Lubrication Layer Thickness And Composition Through Reverse Engineering Of Interface Rheometry Tests, Alexis Salinas, Dimitri Feys

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

During concrete pumping, a lubrication layer is formed near the pipe wall. Extensive research has been performed on measuring and modeling the properties of this layer and using these values to predict pumping pressures. However, there are numerous discussions in the literature about the composition and thickness of this layer: can it be considered mortar, a micromortar, or is it cement paste? In this paper, possible solutions for the thickness and composition of the lubrication layer are derived from interface rheometry tests. It is assumed that the lubrication layer is composed of one or more concentric layers of paste or …


Complexities Observed During The Development Of A Rheological Testing Procedure For Small Cement Paste Samples, Aida Margarita Ley-Hernandez Jan 2020

Complexities Observed During The Development Of A Rheological Testing Procedure For Small Cement Paste Samples, Aida Margarita Ley-Hernandez

Doctoral Dissertations

“Rheology has been widely used to describe the flow properties of fresh cement-based suspensions. The use of a rheometer to characterize these properties is not a straightforward task due to the dependency to different preparation conditions, mixing processes, testing procedures and measuring instruments employed. In addition, shear and time dependency of the material which undergoes chemical and physical particle bonding, caused by hydration of cement and flocculation. Nevertheless, the characterization and understanding of the rheological behavior of cement-based materials have become essential with the recent introduction of novel applications like digital construction in the field of civil engineering, among others. …