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An enormous amount of energy is required to maintain a comfortable indoor temperature. This increases carbon dioxide emission, which is problematic. Phase-change materials have been widely used to resolve this problem and improve the energy efficiency of buildings. However, phase change materials have a fundamental drawback—leakage and low thermal conductivity. A novel thermal energy storage aggregate (TESA) was developed to solve the drawbacks of zeolites impregnated with paraffin wax and coated with epoxy resins, silicon carbide, and silica fume. A mortar which 100% replacement of TESA presented compressive strength that achieved the requirement for building material. To investigate the thermal properties, thermogravimetric analysis (thermally stable below 142 °C), differential scanning calorimetry (melting point: 36.46 °C, freezing point 46.39 °C, latent heat storage capacity: 19.76 J/g), thermal conductivity and thermal behavior of mortar measurements were conducted. Thermal shock cycling was tested to evaluate the reliability of the TESA. Finally, the thermal energy storage performance was evaluated by laboratory-sized cell tests. A laboratory-sized cell test was conducted using a self-designed room model that resemble the actual construction. The indoor temperature of the cell specimen via 100% integration of TESA, reduced the maximum temperature during the heating period by approximately 22% compared with the control cell specimen. The experimental results indicate that TESA can be applied to wall-plastering cement mortar, reducing energy consumption by decreasing the indoor temperature and reducing the temperature fluctuation.
Dong Ho Yoo; In Kyu Jeon; Byeong Hun Woo; Hong Gi Kim. Performance of energy storage system containing cement mortar and PCM/epoxy/SiC composite fine aggregate. Applied Thermal Engineering 2021, 198, 117445 .
AMA StyleDong Ho Yoo, In Kyu Jeon, Byeong Hun Woo, Hong Gi Kim. Performance of energy storage system containing cement mortar and PCM/epoxy/SiC composite fine aggregate. Applied Thermal Engineering. 2021; 198 ():117445.
Chicago/Turabian StyleDong Ho Yoo; In Kyu Jeon; Byeong Hun Woo; Hong Gi Kim. 2021. "Performance of energy storage system containing cement mortar and PCM/epoxy/SiC composite fine aggregate." Applied Thermal Engineering 198, no. : 117445.
Incineration bottom ash is generated by the incineration of solid waste. Household solid waste is increasing every year and so is incineration bottom ash. This is a problem to treat the incineration bottom ash because the ash has many toxic components. Cement composites can solve this problem and there are many studies for using the bottom ash as fine aggregate. To evaluate the usage of incineration bottom ash, compressive strength, mercury intrusion porosimetry, scanning electron microscopy-backscatter electron, X-ray diffraction, and toxicity characteristic leaching processes were performed. When using incineration bottom ash up to 20% of substitution, the compressive strength in all cases was increased. This study showed how the filler effect appeared well in the cement composites through the scanning electron microscopy-backscatter electron, and mercury intrusion porosimetry. X-ray diffraction indicated the possibility of an alkali-silica reaction of the aggregate with the components of incineration bottom ash. This problem is an obstacle to applying the incineration bottom ash as a fine aggregate. In addition, the toxicity characteristic leaching process was shown to be under the threshold of the Korean standard, however, this should nuanced by the consideration of amorphity. Comprehensively, incineration bottom ash could be used as a fine aggregate of up to 20% of substitution. However, the pre-treatment would need to eliminate or reduce alkali reactive components and heavy metals.
Byeong-Hun Woo; In-Kyu Jeon; Dong-Ho Yoo; Seong-Soo Kim; Jeong-Bae Lee; Hong-Gi Kim. Utilization of Municipal Solid Waste Incineration Bottom Ash as Fine Aggregate of Cement Mortars. Sustainability 2021, 13, 8832 .
AMA StyleByeong-Hun Woo, In-Kyu Jeon, Dong-Ho Yoo, Seong-Soo Kim, Jeong-Bae Lee, Hong-Gi Kim. Utilization of Municipal Solid Waste Incineration Bottom Ash as Fine Aggregate of Cement Mortars. Sustainability. 2021; 13 (16):8832.
Chicago/Turabian StyleByeong-Hun Woo; In-Kyu Jeon; Dong-Ho Yoo; Seong-Soo Kim; Jeong-Bae Lee; Hong-Gi Kim. 2021. "Utilization of Municipal Solid Waste Incineration Bottom Ash as Fine Aggregate of Cement Mortars." Sustainability 13, no. 16: 8832.
To solve the problem of black ice, many studies are being carried out. The key in recent days is enhancing the thermal conductivity of concrete. In this study, to improve the thermal conductivity, silicon carbide was used to substitute 50% and 100% of the fine aggregate. In addition, steel fiber is not only for enhancing the mechanical properties but could enhance thermal conductive material. Hence, the arched-type steel fiber was used up to a 1% volume fraction in this study. Furthermore, graphite was used for 5% of the volume fraction for enhancing the thermal conductivity. However, thermal damage would occur due to the difference in thermal conductivity between materials. Therefore, the thermal durability must be verified first. The target application of the concrete in this study was its use as road paving material. To evaluate the thermal durability, freeze–thaw and rapid cyclic thermal attacks were performed. The thermal conductivity of the specimens was increased with the increase in thermal conductive materials. Graphite has already been reported to have a negative effect on mechanical properties, and the results showed that this was the case. However, the steel fiber compensated for the negative effect of graphite, and the silicon carbide provided a filler effect. Graphite also had a negative effect on the freeze–thaw and rapid cyclic thermal attack, but the steel fiber compensated for the reduction in thermal durability. The silicon carbide also helped to improve the thermal durability in the same way as steel fiber. Comprehensively, the steel fiber enhanced all of the properties of the tests. Using 100% silicon carbide was considered the acceptable range, but 50% of silicon carbide was the best. Graphite decreased all the properties except for the thermal conductivity. Therefore, the content of graphite or using other conductive materials used should be carefully considered in further studies.
Byeong-Hun Woo; Dong-Ho Yoo; Seong-Soo Kim; Jeong-Bae Lee; Jae-Suk Ryou; Hong-Gi Kim. Effects of Thermal Conductive Materials on the Freeze-Thaw Resistance of Concrete. Materials 2021, 14, 4063 .
AMA StyleByeong-Hun Woo, Dong-Ho Yoo, Seong-Soo Kim, Jeong-Bae Lee, Jae-Suk Ryou, Hong-Gi Kim. Effects of Thermal Conductive Materials on the Freeze-Thaw Resistance of Concrete. Materials. 2021; 14 (15):4063.
Chicago/Turabian StyleByeong-Hun Woo; Dong-Ho Yoo; Seong-Soo Kim; Jeong-Bae Lee; Jae-Suk Ryou; Hong-Gi Kim. 2021. "Effects of Thermal Conductive Materials on the Freeze-Thaw Resistance of Concrete." Materials 14, no. 15: 4063.
This study focused on the assessment of the ice-melting performance of cement composites using silicon carbide as fine aggregate. To assess the ice-melting performance, two mechanical and three thermal properties were measured and the results were discussed. After measuring the mechanical and thermal properties, the ice-melting test was conducted to confirm the ice-melting performance and the mechanical variation was confirmed through a splitting tensile test. The specimen that used 30% of silicon carbide as fine aggregate showed the highest compressive strength of 68.24 MPa at the 28 days of curing age and the specimens that used 100% of silicon carbide as fine aggregate were the lowest compressive strength of 38.93 MPa at the 28 days of curing age. However, the compressive strength that the case of used 100% of silicon carbide was in the acceptable range. The flexural strength increased with silicon carbide contents of up to 70%. The thermal properties including the thermal conductivity, diffusivity, and specific heat capacity showed nearly the same behaviors. These properties increased with the increase of silicon carbide content. The reason for this phenomenon was related to the volumetric occupancy of silicon carbide in the cement composite. The ice-melting test showed the decreasing of melting time with the increase of the silicon carbide content. Comprehensively, it was demonstrated that the ice-melting performance enhanced for the same reason as the thermal properties and, silicon carbide could be used as fine aggregate for improving the thermal properties.
Byeong Hun Woo; In Kyu Jeon; Dong Ho Yoo; Hong Gi Kim; Jae-Suk Ryou. Ice-melting performance assessment of cement composites using silicon carbide as fine aggregate. Applied Thermal Engineering 2021, 194, 117113 .
AMA StyleByeong Hun Woo, In Kyu Jeon, Dong Ho Yoo, Hong Gi Kim, Jae-Suk Ryou. Ice-melting performance assessment of cement composites using silicon carbide as fine aggregate. Applied Thermal Engineering. 2021; 194 ():117113.
Chicago/Turabian StyleByeong Hun Woo; In Kyu Jeon; Dong Ho Yoo; Hong Gi Kim; Jae-Suk Ryou. 2021. "Ice-melting performance assessment of cement composites using silicon carbide as fine aggregate." Applied Thermal Engineering 194, no. : 117113.
Dust exposure is a serious threat to human health due to dermal contact, inhalation, and ingestion. Children are more vulnerable to dust than adults as a result of high rates of unintentional, or deliberate, ingestion and inhalation of dust. In this study, dust reduction in the playground due to coating of the soil particles with a PVA/PVAc-based solution was investigated. Soil particles were coated with varying amounts of coating solution and the samples were examined for various parameters e.g., specific density, moisture content, liquid and plastic limits, permeability, dust generation due to wind effect and human activity. The results demonstrated that coated soil samples showed improved permeability characteristics and reduced dust generation. These characteristics were improved by increased content of coating solution.
In Jeon; Abdul Qudoos; Hyunseok Lee; Hong Kim. Effect of PVA/PVAc Based Polymer Coating on Dust Reduction in Playground. Applied Sciences 2021, 11, 3144 .
AMA StyleIn Jeon, Abdul Qudoos, Hyunseok Lee, Hong Kim. Effect of PVA/PVAc Based Polymer Coating on Dust Reduction in Playground. Applied Sciences. 2021; 11 (7):3144.
Chicago/Turabian StyleIn Jeon; Abdul Qudoos; Hyunseok Lee; Hong Kim. 2021. "Effect of PVA/PVAc Based Polymer Coating on Dust Reduction in Playground." Applied Sciences 11, no. 7: 3144.
When concrete structures are exposed to fire and high temperatures for an extended period of time, they become significantly less durable due to the decomposition of major hydration products and the evaporation of capillary water. A change in internal properties does not guarantee the stability of concrete structures and may reduce their life cycle. To preserve the durability and stability of concrete structures upon exposure to fire and high temperatures, fire-resistant mortar for exterior walls was developed in this work using zeolite, a phase change material (PCM), and magnesium hydroxide (MH). Zeolite was first coated with paraffin wax. Primary coated aggregates were then coated with MH, which was mixed with dissolved polyvinyl acetate to enhance adhesion on the surface of pre-coated aggregates. The physical and chemical properties of mortar mixed with different percentages of coated aggregates as a replacement for normal aggregates were evaluated by compressive strength tests, X-ray diffraction (XRD), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). Fire-resistant properties were investigated by residual compressive strength measurement tests, mass loss calculations, and mock-up tests to compare the internal temperature of mortar covered with normal and coated aggregate when heated in an electric furnace at 1000 °C. The residual compressive strength results showed a decrease in strength with a larger percentage of coated aggregates in the mortar. However, according to the mock-up test, control mortar covered with plain mortar took 5430 s (90.5 min) to reach a maximum temperature of 842 °C, while the mortar covered with 100% coated aggregate took 7170 s (119.5 min) to reach a maximum temperature of 735 °C. The obtained results indicate that the coated aggregate is a proper replacement for conventional aggregate in the development of fire-resistant mortar.
Dong Ho Yoo; In Kyu Jeon; Hong Gi Kim; Jun Suk Lee; Jae-Suk Ryou. Experimental evaluation of fire resistance performance of cement mortar with PCM/Mg(OH)2-based composite fine aggregate. Construction and Building Materials 2021, 287, 123018 .
AMA StyleDong Ho Yoo, In Kyu Jeon, Hong Gi Kim, Jun Suk Lee, Jae-Suk Ryou. Experimental evaluation of fire resistance performance of cement mortar with PCM/Mg(OH)2-based composite fine aggregate. Construction and Building Materials. 2021; 287 ():123018.
Chicago/Turabian StyleDong Ho Yoo; In Kyu Jeon; Hong Gi Kim; Jun Suk Lee; Jae-Suk Ryou. 2021. "Experimental evaluation of fire resistance performance of cement mortar with PCM/Mg(OH)2-based composite fine aggregate." Construction and Building Materials 287, no. : 123018.
In this paper, the effect of nano-SiO2 (NS) and MgO on the hydration characteristics and anti-washout resistance of non-dispersible underwater concrete (UWC) was evaluated. A slump flow test, a viscosity test, and setting time measurement were conducted to identify the impacts of NS and MgO on the rheological properties of UWC. The pH and turbidity were measured to investigate the anti-washout performance of UWC mixes. To analyze the hydration characteristics and mechanical properties, hydration heat analysis, a compressive strength test, and thermogravimetric analyses were conducted. The experimental results showed that the fine particles of NS and MgO reduced slump flow, increased viscosity, and enhanced the anti-washout resistance of UWC. In addition, both NS and MgO shortened the initial and final setting times, and the replacement of MgO specimens slightly prolonged the setting time. NS accelerated the peak time and increased the peak temperature, and MgO delayed the hydration process and reduced the temperature due to the formation of brucite. The compressive results showed that NS improved the compressive strength of the UWC, and MgO slightly decreased the strength. The addition of NS also resulted in the formation of extra C–S–H, and the replacement of MgO caused the generation of a hydrotalcite phase.
In Jeon; Byeong Woo; Dong Yoo; Jae Ryou; Hong Kim. Evaluation of the Hydration Characteristics and Anti-Washout Resistance of Non-Dispersible Underwater Concrete with Nano-SiO2 and MgO. Materials 2021, 14, 1328 .
AMA StyleIn Jeon, Byeong Woo, Dong Yoo, Jae Ryou, Hong Kim. Evaluation of the Hydration Characteristics and Anti-Washout Resistance of Non-Dispersible Underwater Concrete with Nano-SiO2 and MgO. Materials. 2021; 14 (6):1328.
Chicago/Turabian StyleIn Jeon; Byeong Woo; Dong Yoo; Jae Ryou; Hong Kim. 2021. "Evaluation of the Hydration Characteristics and Anti-Washout Resistance of Non-Dispersible Underwater Concrete with Nano-SiO2 and MgO." Materials 14, no. 6: 1328.
Magnesium phosphate cements are normally referred as chemically bonded ceramic materials and have a vast range of potential applications, due to their excellent performance. This study aims to investigate the effects of carbonation curing on hydration and microstructure of magnesium potassium phosphate (MKPC) concrete. Concrete specimens were prepared and cured in ambient as well as carbonation curing environment. The performance of MKPC concrete specimens were examined via compressive strength and nano indentation tests. In addition, microstructure, and hydration products of MKPC specimens on carbonation curing were investigated via Backscatter electron microscopy (BSEM), Energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and Thermogravimetric analysis (TGA). Experimental results show that the MKPC concrete with carbonation curing represents increased mechanical properties compared to uncarbonated MKPC concrete specimens. The results also showed that the production of magnesium carbonate like Nesquehonite under carbonation had a filling effect that refined the microstructure and enhanced the mechanical properties of the composites.
In Kyu Jeon; Abdul Qudoos; Hong Gi Kim. Influence of carbonation curing on hydration and microstructure of magnesium potassium phosphate cement concrete. Journal of Building Engineering 2021, 38, 102203 .
AMA StyleIn Kyu Jeon, Abdul Qudoos, Hong Gi Kim. Influence of carbonation curing on hydration and microstructure of magnesium potassium phosphate cement concrete. Journal of Building Engineering. 2021; 38 ():102203.
Chicago/Turabian StyleIn Kyu Jeon; Abdul Qudoos; Hong Gi Kim. 2021. "Influence of carbonation curing on hydration and microstructure of magnesium potassium phosphate cement concrete." Journal of Building Engineering 38, no. : 102203.
This study used PCM/SiC-based composite aggregates made using slag aggregate, paraffin wax, and silicon carbide. Concrete samples were prepared by replacing natural coarse aggregates with PCM/SiC-based composite aggregates at various replacement ratios. Compressive strength tests, Fourier-transform infrared spectroscopy, thermogravimetric analysis, X-ray diffraction, and scanning electron microscopy-energy dispersive microscopy analysis were carried out to investigate the mechanical, physical, and microstructural properties of concrete samples. The results reveal that physical properties of the concrete samples made with PCM/SiC-based composite aggregate were less desirable than those made without PCM/SiC-based composite aggregates. However, the targeted designed strength was not compromised with the addition of PCM/SiC-based composite aggregate. The results of microstructural analyses confirmed the presence of various hydration products, paraffin wax, and SiC particles in the cement composites.
Hong Gi Kim; Abdul Qudoos; In Kyu Jeon; Jae Suk Ryou. Assessment of PCM/SiC-based composite aggregate in concrete: Mechanical, physical and microstructural properties. Construction and Building Materials 2020, 262, 120088 .
AMA StyleHong Gi Kim, Abdul Qudoos, In Kyu Jeon, Jae Suk Ryou. Assessment of PCM/SiC-based composite aggregate in concrete: Mechanical, physical and microstructural properties. Construction and Building Materials. 2020; 262 ():120088.
Chicago/Turabian StyleHong Gi Kim; Abdul Qudoos; In Kyu Jeon; Jae Suk Ryou. 2020. "Assessment of PCM/SiC-based composite aggregate in concrete: Mechanical, physical and microstructural properties." Construction and Building Materials 262, no. : 120088.
This work investigates the thermal energy storage performance of concrete using a phase change material (PCM)/SiC-based composite aggregate made with paraffin wax, silicon carbide, and slag aggregate. The thermal energy storage properties were evaluated using a differential scanning calorimetry (DSC) curve, thermal conductivity, hydration heat development, and internal temperature measurements. In addition, a mock-up concrete structure was constructed to evaluate thermal energy storage under natural conditions. The DSC curve showed that the PCM/SiC-based composite aggregate changed its phase and stored thermal energy at 33–34 °C. The internal temperature test indicated that the temperature of the sample with PCM/SiC-based composite aggregate was approximately 2–10 °C higher because of the thermal heat storage capacity of the PCM/SiC-based composite aggregate. A wall surface temperature of 42 °C and 45 °C, respectively at the internal and external side of the energy storage structure wall was measured. While an indoor temperature of 35 °C was observed for energy storage structure. However, the internal surface temperature of the plain structure wall and the indoor room temperature were 41 °C and 38 °C, respectively. The concrete structure with PCM/SiC-based composite aggregate decreased the room temperature and stored thermal energy of approximately 3 °C.
Hong Gi Kim; Abdul Qudoos; In Kyu Jeon; Byeong Hun Woo; Jae Suk Ryou. Assessment of PCM/SiC-based composite aggregate in concrete: Energy storage performance. Construction and Building Materials 2020, 258, 119637 .
AMA StyleHong Gi Kim, Abdul Qudoos, In Kyu Jeon, Byeong Hun Woo, Jae Suk Ryou. Assessment of PCM/SiC-based composite aggregate in concrete: Energy storage performance. Construction and Building Materials. 2020; 258 ():119637.
Chicago/Turabian StyleHong Gi Kim; Abdul Qudoos; In Kyu Jeon; Byeong Hun Woo; Jae Suk Ryou. 2020. "Assessment of PCM/SiC-based composite aggregate in concrete: Energy storage performance." Construction and Building Materials 258, no. : 119637.
The worldwide production of cement is growing every year due to its increased use in the construction. Cement production is affiliated with an environmental concern as it contributes to the CO2 emissions. It is imperative to reduce the cement production by incorporating supplementary cementitious materials in the cement composites. In this research study, wheat straw ash (WSA) was used as an alternate of ordinary Portland cement. The ash was ground separately with a ball mill and a disintegrator mill as well as with a combination of both to enhance its pozzolanic efficiency. Mortar and paste specimens were made by substituting cement with WSA (20% by weight). Ash specimens were examined in terms of particle size distribution, X-ray diffraction, and X-ray fluorescence analyses. The performance of the ash specimens in cement composites was examined via compressive and flexural strengths, and ultrasonic pulse velocity (UPV) tests. Isothermal calorimetric, thermogravimetric analyses (TGA), mercury intrusion porosimetry (MIP), and scanning electron microscopy (SEM) were also employed on the specimens. The results revealed that the particle size of the wheat straw ash specimens significantly reduced and specific surface area enhanced when ground with a combination of both milling techniques. Cement composites made with this type of ash demonstrated improved mechanical and physical properties, accelerated hydration reaction at the early ages, reduce calcium hydroxide content at the later ages, and densified microstructure.
Abdul Qudoos; Ehsanullah Kakar; Atta Ur Rehman; In Kyu Jeon; Hong Gi Kim. Influence of Milling Techniques on the Performance of Wheat Straw Ash in Cement Composites. Applied Sciences 2020, 10, 3511 .
AMA StyleAbdul Qudoos, Ehsanullah Kakar, Atta Ur Rehman, In Kyu Jeon, Hong Gi Kim. Influence of Milling Techniques on the Performance of Wheat Straw Ash in Cement Composites. Applied Sciences. 2020; 10 (10):3511.
Chicago/Turabian StyleAbdul Qudoos; Ehsanullah Kakar; Atta Ur Rehman; In Kyu Jeon; Hong Gi Kim. 2020. "Influence of Milling Techniques on the Performance of Wheat Straw Ash in Cement Composites." Applied Sciences 10, no. 10: 3511.
Increasing use of cement in the construction industry is causing an alarming increase in carbon dioxide (CO2) emissions, which is a serious environmental threat, it can be reduced by the addition of supplementary cementitious materials (SCMs). The commonly used SCMs like ground granulated blast furnace slag (GGBS), metakaolin (MK) and fly ash (FA) have been successfully used to replace the cement partially or completely. Polysilicon sludge obtained from the photovoltaic industry is also a type of waste material that can be used as SCM because it has high content of reactive SiO2. This study investigates the effects of replacing cement with polysilicon sludge in concrete. Different concrete specimens were made by replacing varying proportions of cement with polysilicon sludge and their properties, such as, fresh properties, compressive strength, heat release, chloride penetration, freeze/thaw resistance and microstructural investigations were determined. The results demonstrate that the polysilicon sludge can be used effectively to replace cement, and environmental threats associated with its disposal can be reduced.
Abdul Qudoos; In Kyu Jeon; Seong Soo Kim; Jeong Bae Lee; Hong Gi Kim. Utilization of Waste Polysilicon Sludge in Concrete. Materials 2020, 13, 251 .
AMA StyleAbdul Qudoos, In Kyu Jeon, Seong Soo Kim, Jeong Bae Lee, Hong Gi Kim. Utilization of Waste Polysilicon Sludge in Concrete. Materials. 2020; 13 (1):251.
Chicago/Turabian StyleAbdul Qudoos; In Kyu Jeon; Seong Soo Kim; Jeong Bae Lee; Hong Gi Kim. 2020. "Utilization of Waste Polysilicon Sludge in Concrete." Materials 13, no. 1: 251.
Globally, concrete is the most widely used construction material. The composition of concrete plays an important role in controlling its overall performance. Concrete is composed of approximately 70%-80% aggregates, by volume. Therefore, it is mandatory to investigate the effect of aggregates on the performance of concrete. For this purpose, this study investigated the effect of three different coarse aggregates on the mechanical properties, durability, and microstructure of concrete. Concrete specimens were made using aggregates obtained from three regions with different mineralogies. The specimens were also made by replacing cement with silica fume. The specimens were analyzed in terms of compressive, flexural, and splitting tensile strengths, chloride penetration, carbonation, mercury intrusion porosimetry, and scanning electron microscopy. The results demonstrate that the specimens made with rougher coarse aggregates and silica fume had enhanced performance in comparison to those made with smoother aggregates.
Seong Soo Kim; Abdul Qudoos; Sadam Hussain Jakhrani; Jeong Bae Lee; Hong Gi Kim. Influence of Coarse Aggregates and Silica Fume on the Mechanical Properties, Durability, and Microstructure of Concrete. Materials 2019, 12, 3324 .
AMA StyleSeong Soo Kim, Abdul Qudoos, Sadam Hussain Jakhrani, Jeong Bae Lee, Hong Gi Kim. Influence of Coarse Aggregates and Silica Fume on the Mechanical Properties, Durability, and Microstructure of Concrete. Materials. 2019; 12 (20):3324.
Chicago/Turabian StyleSeong Soo Kim; Abdul Qudoos; Sadam Hussain Jakhrani; Jeong Bae Lee; Hong Gi Kim. 2019. "Influence of Coarse Aggregates and Silica Fume on the Mechanical Properties, Durability, and Microstructure of Concrete." Materials 12, no. 20: 3324.
Exposure of concrete to aggressive environments such as sewage drains can cause significant damage to the concrete and decrease its durability. Fillers can be used to improve the resistance of cement concrete against aggressive environment. In this study, silicon carbide was used as a partial replacement for fine aggregate in fractions up to 10% by weight. Specimens were fabricated and exposed to water and sulfuric acid solution. The specimens were examined for various parameters i.e. mass change, compressive strength change, ultrasonic pulse velocity, thermogravimetric analysis, Fourier transform infrared spectroscopy, X-ray diffraction analysis, and scanning electron microscopy. The results indicate that silicon carbide particles play an important role by filling the pores inside the cement composites and densifying the microstructure due to the filler effect. The cement mortars containing silicon carbide showed improved resistance to sulfuric acid attack and this behavior was enhanced with the increase in silicon carbide content.
In Kyu Jeon; Abdul Qudoos; Sadam Hussain Jakhrani; Hong Gi Kim; Jae-Suk Ryou. Investigation of sulfuric acid attack upon cement mortars containing silicon carbide powder. Powder Technology 2019, 359, 181 -189.
AMA StyleIn Kyu Jeon, Abdul Qudoos, Sadam Hussain Jakhrani, Hong Gi Kim, Jae-Suk Ryou. Investigation of sulfuric acid attack upon cement mortars containing silicon carbide powder. Powder Technology. 2019; 359 ():181-189.
Chicago/Turabian StyleIn Kyu Jeon; Abdul Qudoos; Sadam Hussain Jakhrani; Hong Gi Kim; Jae-Suk Ryou. 2019. "Investigation of sulfuric acid attack upon cement mortars containing silicon carbide powder." Powder Technology 359, no. : 181-189.
This study investigates the potential of light-burnt dolomite (LBD) as a supplementary cementitious material with ground granulated blast furnace slag (GGBFS) and Ordinary Portland cement (OPC). In this work, LBD was substituted for up to 20% of GGBFS in sodium sulfate-activated slag systems. The effects of LBD incorporation on the flow, setting time, compressive and flexural strength development, and drying shrinkage were explored with, X-ray diffraction and thermogravimetric analyses. LBD incorporation resulted in greater strength development of an alkali-activated slag system. The optimum LBD content for strength development was 10%, regardless of ordinary Portland cement content. In addition, LBD decreased the drying shrinkage, accelerated the hydration process, and induced hydrotalcite formation, which can be attributed to the reactive MgO inside LBD.
In Kyu Jeon; Jae Suk Ryou; Sadam Hussain Jakhrani; Hong Gi Kim. Effects of Light-Burnt Dolomite Incorporation on the Setting, Strength, and Drying Shrinkage of One-Part Alkali-Activated Slag Cement. Materials 2019, 12, 2874 .
AMA StyleIn Kyu Jeon, Jae Suk Ryou, Sadam Hussain Jakhrani, Hong Gi Kim. Effects of Light-Burnt Dolomite Incorporation on the Setting, Strength, and Drying Shrinkage of One-Part Alkali-Activated Slag Cement. Materials. 2019; 12 (18):2874.
Chicago/Turabian StyleIn Kyu Jeon; Jae Suk Ryou; Sadam Hussain Jakhrani; Hong Gi Kim. 2019. "Effects of Light-Burnt Dolomite Incorporation on the Setting, Strength, and Drying Shrinkage of One-Part Alkali-Activated Slag Cement." Materials 12, no. 18: 2874.
The purpose of this study was to prevent early age autogenous shrinkage in high-strength mortars with saturated tea waste particles. In general, high strength and high performance concretes are made with low water/binder ratios; hence, they are susceptible to shrink at early ages. This shrinkage occurs due to self-desiccation that leads to autogenous shrinkage. To overcome self-desiccation problems in high-strength cement composites, it is necessary to keep the composites moist for a long time. Pre-saturated porous lightweight aggregates and super absorbent polymers are the most commonly used materials in high-strength cement composites to keep them moist for a long time; however, in this study, porous tea waste particles were used to keep the cement mortars moist. Pre-saturated tea waste particles were used in two different size proportions, making up as much as 3% of the volume of the binder. Moreover, commonly used lightweight aggregate (perlite) was also used to compare the outcomes of specimens made with tea waste particles. Different parameters were observed, such as, flow of fresh mortars, autogenous shrinkage, mechanical strengths and microstructure of specimens. The addition of tea waste and perlite particles in mortars made with Ordinary Portland cement (OPC) as the only binder, showed a reduction in flow, autogenous shrinkage and mechanical strengths, as compared to mixes made with partial addition of silica fume. Although, the use of silica fume improved the mechanical strength of specimens. Moreover, the use of saturated tea waste and perlite particles also improved the microstructure of specimens at an age of 28 days. The results revealed that the saturated tea waste particles have the ability to prevent autogenous shrinkage but they reduce strength of high-strength mortars at early ages.
Sadam Hussain Jakhrani; Jae Suk Ryou; Atta- Ur- Rehman; In Kyu Jeon; Byeong Hun Woo; Hong Gi Kim. Prevention of Autogenous Shrinkage in High-Strength Mortars with Saturated Tea Waste Particles. Materials 2019, 12, 2654 .
AMA StyleSadam Hussain Jakhrani, Jae Suk Ryou, Atta- Ur- Rehman, In Kyu Jeon, Byeong Hun Woo, Hong Gi Kim. Prevention of Autogenous Shrinkage in High-Strength Mortars with Saturated Tea Waste Particles. Materials. 2019; 12 (17):2654.
Chicago/Turabian StyleSadam Hussain Jakhrani; Jae Suk Ryou; Atta- Ur- Rehman; In Kyu Jeon; Byeong Hun Woo; Hong Gi Kim. 2019. "Prevention of Autogenous Shrinkage in High-Strength Mortars with Saturated Tea Waste Particles." Materials 12, no. 17: 2654.
The main purpose of this work is to study the effect of saturated black tea waste and perlite on controlling the rapid heat of hydration in high-strength cement mortars at early ages. Tea waste and perlite were investigated as internal curing agents in different mixes. Mortar specimens with two different sizes of tea waste and perlite particles with 1 and 3% by volume of cement were added in different mixes to find their effect on early age hydration. The rising interior temperature, setting times, and strength parameters were evaluated. Results showed that the mix specimens that contained 3% tea waste and perlite particles significantly delayed the hydration process by minimizing internal temperature and extended setting times of different specimens. However, their usage had a slightly adverse impact on compressive and flexural strengths. It was observed that the specimens made with coarser particles of tea waste and perlite were more helpful to control early age rapid hydration than the specimens made with finer particles, whereas the specimens made with finer particles had slightly higher strengths than the specimens made with coarser particles. Hence, the coarser particles are recommended to be used in high-strength mortars to mitigate the early age rapid heat of hydration.
Sadam Hussain Jakhrani; Hong Gi Kim; In Kyu Jeon; Jae Suk Ryou. Effect of Saturated Tea Waste and Perlite Particles on Early Age Hydration of High-Strength Cement Mortars. Materials 2019, 12, 2269 .
AMA StyleSadam Hussain Jakhrani, Hong Gi Kim, In Kyu Jeon, Jae Suk Ryou. Effect of Saturated Tea Waste and Perlite Particles on Early Age Hydration of High-Strength Cement Mortars. Materials. 2019; 12 (14):2269.
Chicago/Turabian StyleSadam Hussain Jakhrani; Hong Gi Kim; In Kyu Jeon; Jae Suk Ryou. 2019. "Effect of Saturated Tea Waste and Perlite Particles on Early Age Hydration of High-Strength Cement Mortars." Materials 12, no. 14: 2269.
Jun Hyeong Kim; Jae-Suk Ryou; Hong Gi Kim; Tae Ho Ahn; Yong-Soo Lee; Abdul Qudoos. Self-healing phenomena using PVA coated granules for sustainable construction. Journal of Ceramic Processing Research 2019, 20, 70 -76.
AMA StyleJun Hyeong Kim, Jae-Suk Ryou, Hong Gi Kim, Tae Ho Ahn, Yong-Soo Lee, Abdul Qudoos. Self-healing phenomena using PVA coated granules for sustainable construction. Journal of Ceramic Processing Research. 2019; 20 (null):70-76.
Chicago/Turabian StyleJun Hyeong Kim; Jae-Suk Ryou; Hong Gi Kim; Tae Ho Ahn; Yong-Soo Lee; Abdul Qudoos. 2019. "Self-healing phenomena using PVA coated granules for sustainable construction." Journal of Ceramic Processing Research 20, no. null: 70-76.
Photocatalytic cementitious materials are used in the exterior of the buildings and infrastructure for self-cleaning and air-purifying purposes. These materials are exposed to the aggressive exposure conditions like acid rain, runoff water and are subjected to the deterioration due to the leaching of calcium. The knowledge of leaching attack upon photocatalytic cementitious materials after the addition of nano-materials is necessary. In the current study, the influence of nano-silica addition on the leaching attack upon photocatalytic cement mortars was thoroughly investigated. For this purpose, photocatalytic mortars were made by adding 3% TiO2 and variable amount (0–2%) of nano-silica. Accelerated leaching environment was created by immersing mortars in 6 M ammonium nitrate (NH4NO3) solution. The progressive development of the leaching depth in mortars was measured. The loss of hardened properties was monitored by evaluating the compressive strength, flexural strength, porosity, and dynamic modulus of elasticity. X-ray diffraction, thermogravimetry, Fourier transform infrared spectroscopy, scanning electron microscopy tests were conducted to know the microstructural deteriorations. Results indicated that the leaching attack induced mechanical and microstructural damages in the mortars, but the addition of nano-silica decreased mechanical and microstructural damages in the photocatalytic mortars and increased the resistance of photocatalytic mortars to leaching attack.
Atta- Ur- Rehman; Abdul Qudoos; Sadam Hussain Jakhrani; Hong Gi Kim; Jae-Suk Ryou. Influence of Nano-silica on the Leaching Attack upon Photocatalytic Cement Mortars. International Journal of Concrete Structures and Materials 2019, 13, 35 .
AMA StyleAtta- Ur- Rehman, Abdul Qudoos, Sadam Hussain Jakhrani, Hong Gi Kim, Jae-Suk Ryou. Influence of Nano-silica on the Leaching Attack upon Photocatalytic Cement Mortars. International Journal of Concrete Structures and Materials. 2019; 13 (1):35.
Chicago/Turabian StyleAtta- Ur- Rehman; Abdul Qudoos; Sadam Hussain Jakhrani; Hong Gi Kim; Jae-Suk Ryou. 2019. "Influence of Nano-silica on the Leaching Attack upon Photocatalytic Cement Mortars." International Journal of Concrete Structures and Materials 13, no. 1: 35.
Atta- Ur- Rehmana; Jae-Suk Ryou; Sadam Hussain Jakhrani; Hong Gi Kim; Jeong Bae Lee; Abdul Qudoos. Influence of nano silica on the fresh, hardened and durability properties of self-cleaning white Portland cement mortars. Journal of Ceramic Processing Research 2019, 20, 270 -275.
AMA StyleAtta- Ur- Rehmana, Jae-Suk Ryou, Sadam Hussain Jakhrani, Hong Gi Kim, Jeong Bae Lee, Abdul Qudoos. Influence of nano silica on the fresh, hardened and durability properties of self-cleaning white Portland cement mortars. Journal of Ceramic Processing Research. 2019; 20 (3):270-275.
Chicago/Turabian StyleAtta- Ur- Rehmana; Jae-Suk Ryou; Sadam Hussain Jakhrani; Hong Gi Kim; Jeong Bae Lee; Abdul Qudoos. 2019. "Influence of nano silica on the fresh, hardened and durability properties of self-cleaning white Portland cement mortars." Journal of Ceramic Processing Research 20, no. 3: 270-275.