The Experts below are selected from a list of 5976 Experts worldwide ranked by ideXlab platform
Raffaele Cioffi - One of the best experts on this subject based on the ideXlab platform.
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use of cement kiln dust blast furnace slag and marble sludge in the manufacture of sustainable Artificial Aggregates by means of cold bonding pelletization
Materials, 2013Co-Authors: Francesco Colangelo, Raffaele CioffiAbstract:In this work, three different samples of solid industrial wastes cement kiln dust (CKD), granulated blast furnace slag and marble sludge were employed in a cold bonding pelletization process for the sustainable production of Artificial Aggregates. The activating action of CKD components on the hydraulic behavior of the slag was explored by evaluating the neo-formed phases present in several hydrated pastes. Particularly, the influence of free CaO and sulfates amount in the two CKD samples on slag reactivity was evaluated. Cold bonded Artificial Aggregates were characterized by determining physical and mechanical properties of two selected size fractions of the granules for each studied mixture. Eighteen types of granules were employed in C28/35 concrete manufacture where coarser natural Aggregate were substituted with the Artificial ones. Finally, lightweight concretes were obtained, proving the suitability of the cold bonding pelletization process in Artificial Aggregate sustainable production.
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use of cement kiln dust blast furnace slag and marble sludge in the manufacture of sustainable Artificial Aggregates by means of cold bonding pelletization
Materials, 2013Co-Authors: Francesco Colangelo, Raffaele CioffiAbstract:In this work, three different samples of solid industrial wastes cement kiln dust (CKD), granulated blast furnace slag and marble sludge were employed in a cold bonding pelletization process for the sustainable production of Artificial Aggregates. The activating action of CKD components on the hydraulic behavior of the slag was explored by evaluating the neo-formed phases present in several hydrated pastes. Particularly, the influence of free CaO and sulfates amount in the two CKD samples on slag reactivity was evaluated. Cold bonded Artificial Aggregates were characterized by determining physical and mechanical properties of two selected size fractions of the granules for each studied mixture. Eighteen types of granules were employed in C28/35 concrete manufacture where coarser natural Aggregate were substituted with the Artificial ones. Finally, lightweight concretes were obtained, proving the suitability of the cold bonding pelletization process in Artificial Aggregate sustainable production.
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manufacture of Artificial Aggregate using mswi bottom ash
Waste Management, 2011Co-Authors: Raffaele Cioffi, Francesco Colangelo, Fabio Montagnaro, L SantoroAbstract:This paper reports the results of an investigation on material recovery by stabilization/solidification of bottom ash coming from a municipal solid waste incineration plant. Stabilization/solidification was carried out to produce Artificial Aggregate in a rotary plate granulator by adding hydraulic binders based on cement, lime and coal fly ash. Different mixes were tested in which the bottom ash content ranged between 60% and 90%. To avoid undesirable swelling in hardened products, the ash was previously milled and then granulated at room temperature. The granules were tested to assess their suitability to be used as Artificial Aggregate through the measurement of the following properties: density, water absorption capacity, compressive strength and heavy metals release upon leaching. It was demonstrated that the granules can be classified as lightweight Aggregate with mechanical strength strongly dependent on the type of binder. Concrete mixes were prepared with the granulated Artificial Aggregate and tested for in-service performance, proving to be suitable for the manufacture of standard concrete blocks in all the cases investigated.
Francesco Colangelo - One of the best experts on this subject based on the ideXlab platform.
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use of cement kiln dust blast furnace slag and marble sludge in the manufacture of sustainable Artificial Aggregates by means of cold bonding pelletization
Materials, 2013Co-Authors: Francesco Colangelo, Raffaele CioffiAbstract:In this work, three different samples of solid industrial wastes cement kiln dust (CKD), granulated blast furnace slag and marble sludge were employed in a cold bonding pelletization process for the sustainable production of Artificial Aggregates. The activating action of CKD components on the hydraulic behavior of the slag was explored by evaluating the neo-formed phases present in several hydrated pastes. Particularly, the influence of free CaO and sulfates amount in the two CKD samples on slag reactivity was evaluated. Cold bonded Artificial Aggregates were characterized by determining physical and mechanical properties of two selected size fractions of the granules for each studied mixture. Eighteen types of granules were employed in C28/35 concrete manufacture where coarser natural Aggregate were substituted with the Artificial ones. Finally, lightweight concretes were obtained, proving the suitability of the cold bonding pelletization process in Artificial Aggregate sustainable production.
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use of cement kiln dust blast furnace slag and marble sludge in the manufacture of sustainable Artificial Aggregates by means of cold bonding pelletization
Materials, 2013Co-Authors: Francesco Colangelo, Raffaele CioffiAbstract:In this work, three different samples of solid industrial wastes cement kiln dust (CKD), granulated blast furnace slag and marble sludge were employed in a cold bonding pelletization process for the sustainable production of Artificial Aggregates. The activating action of CKD components on the hydraulic behavior of the slag was explored by evaluating the neo-formed phases present in several hydrated pastes. Particularly, the influence of free CaO and sulfates amount in the two CKD samples on slag reactivity was evaluated. Cold bonded Artificial Aggregates were characterized by determining physical and mechanical properties of two selected size fractions of the granules for each studied mixture. Eighteen types of granules were employed in C28/35 concrete manufacture where coarser natural Aggregate were substituted with the Artificial ones. Finally, lightweight concretes were obtained, proving the suitability of the cold bonding pelletization process in Artificial Aggregate sustainable production.
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manufacture of Artificial Aggregate using mswi bottom ash
Waste Management, 2011Co-Authors: Raffaele Cioffi, Francesco Colangelo, Fabio Montagnaro, L SantoroAbstract:This paper reports the results of an investigation on material recovery by stabilization/solidification of bottom ash coming from a municipal solid waste incineration plant. Stabilization/solidification was carried out to produce Artificial Aggregate in a rotary plate granulator by adding hydraulic binders based on cement, lime and coal fly ash. Different mixes were tested in which the bottom ash content ranged between 60% and 90%. To avoid undesirable swelling in hardened products, the ash was previously milled and then granulated at room temperature. The granules were tested to assess their suitability to be used as Artificial Aggregate through the measurement of the following properties: density, water absorption capacity, compressive strength and heavy metals release upon leaching. It was demonstrated that the granules can be classified as lightweight Aggregate with mechanical strength strongly dependent on the type of binder. Concrete mixes were prepared with the granulated Artificial Aggregate and tested for in-service performance, proving to be suitable for the manufacture of standard concrete blocks in all the cases investigated.
Kasim Mermerdas - One of the best experts on this subject based on the ideXlab platform.
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influence of Artificial Aggregate on mechanical properties fracture parameters and bond strength of concretes
Construction and Building Materials, 2020Co-Authors: Suleyman Ipek, Olabode Adekunle Ayodele, Kasim MermerdasAbstract:Abstract The paper presented herein investigates the mechanical performance of concrete involving lightweight and normal weight Aggregates with similar compressive strength. For this, two compressive strength values, 25 and 45 MPa, were considered for the concretes produced by normal and lightweight Aggregates. Therefore, four concrete mixtures were designed at different water-to-cement ratios and cement contents. The lightweight Aggregate utilized in this study was produced through cold bonding pelletization of fly ash and cement at ambient temperature in a specially designed tilted pan. The Artificial lightweight Aggregate used as a substitution of natural Aggregate had similar particle size distribution to that of natural Aggregate. The same mixing procedure was adopted to produce concrete and the testing specimens attained from each mixture were cured at the same circumstances. After the 28-day curing period, the specimens were tested for compressive strength and modulus of elasticity, splitting tensile and flexural strengths. Moreover, advanced mechanical properties such as fracture parameters, bond strength between embedded reinforcement and the concrete were also investigated. The test results indicated that it is possible to produce the lightweight Aggregate concrete having similar compressive strength with the natural Aggregate concrete, however, the utilization of Artificial lightweight Aggregates significantly influenced the investigated mechanical and fracture properties of the concretes despite having the similar compressive strengths. But, it was also observed that the utilization of lightweight Aggregate made the concrete more ductile.
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recycling ground granulated blast furnace slag as cold bonded Artificial Aggregate partially used in self compacting concrete
Journal of Hazardous Materials, 2012Co-Authors: Mehmet Gesoglu, Erhan Guneyisi, Swara Fuad Mahmood, Kasim MermerdasAbstract:Ground granulated blast furnace slag (GGBFS), a by-product from iron industry, was recycled as Artificial coarse Aggregate through cold bonding pelletization process. The Artificial slag Aggregates (ASA) replaced partially the natural coarse Aggregates in production of self-compacting concrete (SCC). Moreover, as being one of the most widely used mineral admixtures in concrete industry, fly ash (FA) was incorporated as a part of total binder content to impart desired fluidity to SCCs. A total of six concrete mixtures having various ASA replacement levels (0%, 20%, 40%, 60%, and 100%) were designed with a water-to-binder (w/b) ratio of 0.32. Fresh properties of self-compacting concretes (SCC) were observed through slump flow time, flow diameter, V-funnel flow time, and L-box filling height ratio. Compressive strength of hardened SCCs was also determined at 28 days of curing. It was observed that increasing the replacement level of ASA resulted in decrease in the amount of superplasticizer to achieve a constant slump flow diameter. Moreover, passing ability and viscosity of SCC's enhanced with increasing the amount of ASA in the concrete. The maximum compressive strength was achieved for the SCC having 60% ASA replacement.
Tungchai Ling - One of the best experts on this subject based on the ideXlab platform.
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recent advances in Artificial Aggregate production
Journal of Cleaner Production, 2021Co-Authors: Pengfei Ren, Tungchai LingAbstract:Abstract Artificial Aggregates (AAs) are man-made construction material, and the properties greatly depend on its manufacturing process (e.g. granulation and hardening) and the raw materials (usually different source of wastes) used. This paper reviews the granulation process and suitable raw materials for each hardening method. Hardening methods including sintering, cold-bonding, accelerated carbonation and alkaline activation can significantly impact the final properties of the produced AAs. In general, finer material fractions are required for granulation to increase the pelletization efficiency and strength of AAs. Among the hardening methods, sintering usually gives a better physical and mechanical properties of AAs with a condition that SiO2/∑flux ratio of raw materials used should exceed 2, and (SiO2+Al2O3)/∑flux ratio of between 3.5 and 10. The cold-bonded method requires hydraulic raw materials and is restricted by a longer curing time, but this can be solved by introducing autoclaving or alkaline activation approaches to accelerate the strength gain. Post curing of AAs under a strongly alkaline solution can also effectively reduce the water absorption of Aggregate by nearly 90%. The accelerated carbonation technique seems to be a green and more sustainable hardening method, as it can turn less valuable waste into strength bearing calcite and permanently store the waste CO2 through mineral carbonation. In terms of leachability, sintering can stabilize most heavy metals, while other hardening methods such as cold bonding and carbonation are only effective for stabilizing certain heavy metals.
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strength enhancement of Artificial Aggregate prepared with waste concrete powder and its impact on concrete properties
Journal of Cleaner Production, 2020Co-Authors: Yi Jiang, Tungchai Ling, Minjiao ShiAbstract:Abstract Waste concrete powder (WCP), a byproduct generated in the production of recycled concrete Aggregates, is proposed as the main material for manufacturing Artificial Aggregate (WCPA) through cold-bonding pelletization. The addition of cement, ground granulated blast furnace slag and calcium hydroxide as well as the application of CO2 curing are integrated with the purpose of strength enhancement. Experimental results indicate that Aggregate strength increases in proportion with cement and slag dosages while calcium hydroxide content reaches the optimum at 3%. By optimizing mix proportion, the Aggregate obtains the highest strength of 3.0 MPa and the lowest water absorption of 6.3%. In addition, when it is incorporated in concrete, WCPA shows stronger interactions with cement matrix as compared with natural Aggregate and ceramsite since the width of interfacial transition zone is only 30 μm as compared to 60 μm in the reference groups. The compressive strength of WCPA concrete reaches over 30 MPa, suggesting the viability of WCPA in many civil engineering applications; however, it is found that the drying shrinkage tends to increase by up to 47%. Overall, this study contributes to the establishment of waste to resources chain with regards to the concrete industry through the green production of Artificial Aggregate with WCP.
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turning concrete waste powder into carbonated Artificial Aggregates
Construction and Building Materials, 2019Co-Authors: Minjiao Shi, Tungchai Ling, Binlin Gan, Mingzhi GuoAbstract:Abstract In recent years, sustainable management of construction waste has garnered increasing attention. However, most previous studies mainly focused on turning construction wastes into recycled Aggregates, whereas, recycling of those construction wastes below 5 mm has often been challenged or ignored. This study attempted to effectively deal with such recycled fine powders by employment of granulation technology to produce Artificial Aggregates with a diameter of 5–20 mm. The optimal granulation parameters were identified through a systematic experimental test. Moreover, the effect of water and cement content, as well as curing regimes, on the properties (such as shape and strength) of the prepared Artificial Aggregates was also investigated. More importantly, influence of normal curing and CO2 curing on the strength development of Artificial Aggregates was examined and compared. In doing so, the scheme of preparation of Artificial Aggregates with optimal strength was developed. Findings from this study provide an alternative and viable solution to effectively dealing with construction wastes in an environmentally-friendly way and serve as a reference for follow-up studies in the future. Meanwhile, the carbonated Artificial Aggregate can be potentially used to replace natural Aggregates in the preparation of low-strength concrete and blocks.
Minjiao Shi - One of the best experts on this subject based on the ideXlab platform.
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strength enhancement of Artificial Aggregate prepared with waste concrete powder and its impact on concrete properties
Journal of Cleaner Production, 2020Co-Authors: Yi Jiang, Tungchai Ling, Minjiao ShiAbstract:Abstract Waste concrete powder (WCP), a byproduct generated in the production of recycled concrete Aggregates, is proposed as the main material for manufacturing Artificial Aggregate (WCPA) through cold-bonding pelletization. The addition of cement, ground granulated blast furnace slag and calcium hydroxide as well as the application of CO2 curing are integrated with the purpose of strength enhancement. Experimental results indicate that Aggregate strength increases in proportion with cement and slag dosages while calcium hydroxide content reaches the optimum at 3%. By optimizing mix proportion, the Aggregate obtains the highest strength of 3.0 MPa and the lowest water absorption of 6.3%. In addition, when it is incorporated in concrete, WCPA shows stronger interactions with cement matrix as compared with natural Aggregate and ceramsite since the width of interfacial transition zone is only 30 μm as compared to 60 μm in the reference groups. The compressive strength of WCPA concrete reaches over 30 MPa, suggesting the viability of WCPA in many civil engineering applications; however, it is found that the drying shrinkage tends to increase by up to 47%. Overall, this study contributes to the establishment of waste to resources chain with regards to the concrete industry through the green production of Artificial Aggregate with WCP.
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turning concrete waste powder into carbonated Artificial Aggregates
Construction and Building Materials, 2019Co-Authors: Minjiao Shi, Tungchai Ling, Binlin Gan, Mingzhi GuoAbstract:Abstract In recent years, sustainable management of construction waste has garnered increasing attention. However, most previous studies mainly focused on turning construction wastes into recycled Aggregates, whereas, recycling of those construction wastes below 5 mm has often been challenged or ignored. This study attempted to effectively deal with such recycled fine powders by employment of granulation technology to produce Artificial Aggregates with a diameter of 5–20 mm. The optimal granulation parameters were identified through a systematic experimental test. Moreover, the effect of water and cement content, as well as curing regimes, on the properties (such as shape and strength) of the prepared Artificial Aggregates was also investigated. More importantly, influence of normal curing and CO2 curing on the strength development of Artificial Aggregates was examined and compared. In doing so, the scheme of preparation of Artificial Aggregates with optimal strength was developed. Findings from this study provide an alternative and viable solution to effectively dealing with construction wastes in an environmentally-friendly way and serve as a reference for follow-up studies in the future. Meanwhile, the carbonated Artificial Aggregate can be potentially used to replace natural Aggregates in the preparation of low-strength concrete and blocks.
