• Advances in concrete construction
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• 제15권1호
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• pp.63-74
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• 2023

All production and consumption activities produce wastes, which often cause damage to our environment and multiple risks to the human health. The valorization of these wastes in concrete technology is a future solution that will allow finding other construction materials sources, optimizing energy consumption and protecting the environment. Among these wastes, there is the marble waste. Every year, huge amount of marble waste is discarded as dust or aggregates form, in open-air storage areas causing serious problems for the environment and public health. In this context, the incorporation of marble waste as a replacement of ordinary aggregates or cement in concrete composition is actively investigated by researchers. This paper presents a comprehensive review of published studies over the last 20 years, dealing the effect of marble waste on fresh and hardened properties of concrete. Most of the studies carried out have used marble waste as dust with substitution rates between 5 and 20%. Besides the economic and ecological benefits, this review showed that marble waste can improve the physical, mechanical and durability properties of concrete. This improvement depends on the form (dust, fine aggregate or coarse aggregate), substitution method (as cement or aggregates replacement) and substitution rate of marble waste. Additionally, the review results showed that the use of 10-15% of marble waste dust as cement substitution can lead to increase the compressive strength.

• Advances in concrete construction
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• 제14권1호
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• pp.1-13
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• 2022

Due to the physical-chemical characteristics of some bottom ash (BA), there are technical, economic and environmental limitations to find a destination that will add value to it. In Brazil, this residue is eventually used for filling coal extraction pits or remains in sedimentation ponds, creating a susceptible panorama to environmental issues. The geopolymers binders are one of the alternatives to the proper use high amounts of these materials. In this work, geopolymeric binder pastes were produced with BA mixed to activators with different alkali contents (expressed as %Na₂O), as well as the incorporation of soluble silicates (Ms content). The production of binary geopolymeric pastes based on the use of two industrial wastes: fluid catalytic cracking (FCC) and aluminum anodizing sludge (AAS), was also assessed. The content in mass of BA/FCC and BA/AAS ranged from 100/0, 90/10; 80/20 and 70/30. Systems with soluble silicates as activator in a molar ratio SiO₂/Na₂O of 1.0 (Ms = 1.0) and Na₂O content of 15%, showed the best results of mechanical strength (42 MPa at day 28^th). The improvement is up to 5X when compared to NaOH based systems. For systems with partial replacement of BA of 10% of AAS and 20% of FCC (80/20), the presence of soluble silicates was also effective to increase compressive strength.

• Advances in concrete construction
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• 제4권1호
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• pp.15-26
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• 2016

In Algeria, wastes are often stored in such conditions that do not meet standards. Today and more than ever, we really must implement an environmentally management of wastes. Recovery of waste in Algeria has a considerable delay due to the absence of a policy favorable to the development of waste management. But many researchers have shown the possibility to reuse dredged sediments in road construction. Through Europe, recent research works have been already performed on dam sediments. Present study fits into the context of the valorization of dredged sediments from Fergoug dam. They are found in considerable quantities and mainly composed of mineral phases, organic matters and water. The reservoir sedimentation poses problems for the environment and water storage, dredging becomes necessary. Civil engineering is a common way of recycling for such materials. Dredged sediments have not the required mechanical characteristics recommended by the standards as GTR guide (LCPC-SETRA 1992). So as to obtain mechanical performance, dredged sediment can be treated with cement, lime, or replaced materials like quarry sand. An experimental study has been conducted to determine physical and mechanical characteristics of sediments dredged from dam. Then different mixtures of sediment and/or quarry sand with hydraulic binders are proposed for improving the grain size distribution of the mixes. Finally, according these mixtures, different formulations have been tested as alternative materials with dredged sediments.

• Structural Engineering and Mechanics
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• 제67권1호
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• pp.87-91
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• 2018

Concrete is the most widely used building material all over the world, because of its many technical and economic qualities. This pressure on the concrete resource causes an intensive exploitation of the quarries of aggregates, which results in a exhaustion of these and environmental problems. That is why recycling and valorization of materials are considered as future solutions, to fill the deficit between production and consumption and to protect the environment. This study is part of the valorization process of local materials, which aims to reuse marble waste as fine aggregate (excess loads of marble waste exposed to bad weather conditions) available in the marble quarry of Fil-fila (Skikda, East of Algeria) in the manufacture of self-compacting concretes. It consists of introducing the marble waste as sand into the self-compacting concrete formulation, with variable percentages (25%, 50%, 75% and 100%) and to study the development of its properties both in fresh state (air content, density, slump flow, V-funnel, L-box and sieve stability) as well as the hardened one (compressive strength and flexural strength). The results obtained showed us that marble wastes can be used as sand in the manufacture of self compacting concretes.

• Structural Engineering and Mechanics
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• 제49권4호
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• pp.491-498
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• 2014

During the past years, the protection of the environment has become a major concern out passing the state frontiers to reach a planetary dimension. Depository waste sites have become a serious problem in terms of their locations and costs. On the other hand, the construction industry has a leading place in terms of quantities of waste produced from the start to the end of each construction site, by the large amounts of raw materials used and their respective consequences on the environment. The recycling of quarry wastes products, of demolished concrete, bricks and large quantities of waste resulting from the transformation of marble blocks can provide ideal solutions and advantages for the preservation of the environment, to become a supplementary source of aggregates. The main purpose of this study is to show technically the possibility of recuperating the aggregates of marble wastes as a partial substitute or total in the mortars. The aggregates used in this study is a sand of marble wastes (excess loads of sand exposed to bad weather conditions) of the quarry derived from Fil-fila marble (Skikda, east of Algeria). To achieve this work, we have studied the effect of sand substitution of marble wastes in the mortar with rates of (25, 50, 75, 100%); comparing the results obtained with reference samples (0%), the properties when the samples are fresh, and the mechanical performances of mortars at solid state (loss and gain of weight, dimensional variations). The introduction of recycled sand in the mortars gives good results and can be used as granulates.

• Structural Engineering and Mechanics
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• 제53권6호
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• pp.1241-1251
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• 2015

Faced with the growing needs of material resources and requirements of environmental protection for achieving sustainable development, it has become necessary to study and investigate all possibilities of exploring crushed and dune sand, reusing industrial wastes and by-product, and also applying new technologies including sand concrete which can replace the conventional concretes in certain structures to surmount the deficit on construction materials, conserve natural resources, lessen the burden of pollutants to protect the environment and reduce the consumption of energy sources. This experimental study is a part of development and valorization of local materials project in Skikda region (East of Algeria). It aims at studying the effects of partial replacement of sand with marble waste as fines on several fresh and hardened properties of sand concrete in order to reuse these wastes in the concrete manufacturing, resolve the environmental problems caused by them and find another source of construction materials. To achieve these objectives, an experimental program has been carried out; it was consisted to incorporate different percentages of marble waste fines (2, 4, 6, 8, 10 and 12%) in the formulations of sand concrete and study the development of several mechanical and rheological properties. We are also trying to find the optimal percentage of marble waste fine replaced in sand concrete that makes the strength of the concrete maximum. Obtained results showed that marble waste fines improve the properties of sand concrete and can be used as an additive material in sand concrete formulation.

• Journal of Electrochemical Science and Technology
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• 제8권1호
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• pp.77-86
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• 2017

The valorization of domestic wastes becomes a very important research axis that can reduce the energy consumption and protect our environment. The objective of this study is to remove zinc ions from wastewater by using banana peels after their activation as sensor in the working electrode for an environmental application. Banana peels were dried, crushed and treated with sulfuric acid then mixed with polyaniline to improve their electrical conductivity. Cyclic voltammetry and chronoamperometry were used for electrochemistry tests. The obtained voltammogramms at well optimized conditions of applied potential of -1.3 V/SCE and initial zinc concentration of 0.2M during 2 hours of electrolysis, showed the reduction peak of the zinc at a potential of -1.14 V/SCE, which confirmed the activity of this electrode. The modeling of experimental data revealed that the adsorption was fitted by the Langmuir isotherm with a maximal adsorption capacity of 3.4188 mg/g. Changes in the structure of the powder after the electrosorption was noticed by SEM and EDX. Finally, the dosage of the electrolytic solution showed a diminution of the zinc concentration with yield of 99.99%.

• Advances in concrete construction
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• 제11권2호
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• pp.173-181
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• 2021

The main objective of this work is to contribute to the valorization of plastic and glass waste in the improvement of concrete properties. Waste glass after grinding was used as a partial replacement of the cement with a percentage of 15%. The plastic waste was cut and introduced as fibers with 1% by the total volume of the mixture. Mechanical and durability tests were conducted for various mixtures of concrete as compressive and flexural strengths, water absorption, ultrasonic pulse velocity, and acid attack. Also, other in-depth analyses were performed on samples of each variant such as X-ray diffraction (XRD), thermogravimetric analysis (DSC-TGA), and scanning electron microscope (SEM). The results show that the addition of glass powder or plastic fibers or a combination of both in concrete improved in the compression and flexural strengths in the long term. The highest compressive strength was obtained in the mix which combines the two wastes about 26.72% of increase compared to the control concrete. The flexural strength increased in the mixture containing the glass powder. Therefore, the mixture with two wastes exhibits better resistance to aggressive sulfuric acid attack, and incorporating glass powder improves the ultrasonic pulse velocity.

• International Journal of Concrete Structures and Materials
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• 제6권3호
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• pp.145-153
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• 2012

The aim of this study is to explore the possibility of re-cycling a waste material that is now produced in large quantities, while achieving an improvement of the mechanical properties and durability of the mortar. This study examines the mechanical properties and the durability parameters of mortars incorporating plastics bag wastes (PBW) as fine aggregate by substitution of a variable percentage of sand (10, 20, 30 and 40 %). The influence of the PBW on the, compressive and flexural strength, drying shrinkage, fire resistance, sulfuric acid attack and chloride diffusion coefficient of the different mortars, has been investigated and analyzed in comparison to the control mortar. The results showed that the use of PBW enabled to reduce by 18-23 % the compressive strength of mortars containing 10 and 20 % of waste respectively, which remains always close to the reference mortar (made without waste). The replacement of sand by PBW in mortar slows down the penetration of chloride ions, improves the behavior of mortars in acidic medium and improves the sensitivity to cracking. The results of this investigation consolidate the idea of the use of PBW in the field of construction.

• 한국염색가공학회:학술대회논문집
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• 한국염색가공학회 2012년도 제46차 학술발표회
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• pp.67-67
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• 2012

식생활 및 사회 환경 변화에 따라 식품 폐기물이 많이 발생하고 있다. 이 폐기물을 처리하는 데 막대한 비용이 소요되고 환경오염도 심각한 상황이다. 이에 식품 폐기물의 자원화를 통해 자원의 부가가치를 높이고, 처리비용 절감과 함께 환경오염 방지, 새로운 유기소재의 확보 등의 효과를 볼 것으로 사료된다. 본 연구는 바나나 껍질로부터 추출한 물질의 다양한 기능성을 조사하고, 인디고의 환원제로서 유효성을 확인하여 천연염색 분야에 식품 폐기물의 활용 방안을 모색하는데 목적이 있다. 이를 위하여 바나나 껍질은 건조 후 증류수로 $100^{\circ}C$에서 1시간 동안 추출, 농축하여 분말로 만들어 사용하였다. 바나나 껍질 추출물의 기능성을 알아보기 위해 총당분석(Phenol- sulfuric method), 항산화(DPPH radicals 소거활성), 황색포도상구균에 대한 항균성 실험(Paper disc diffusion)을 하였다. 또한 인디고 염색시 화학환원제 대신 이 분말을 사용하였고, 그 환원력 측정은 환원 포텐셜과 염색 실험을 통해 평가하였다. 본 연구에서 제조한 바나나 껍질 추출물은 항산화능이 우수하였고, 높은 당 함량을 나타냈다. 황색 포도상구균에 대한 항균성을 지녀 향후 기능성 물질로서 응용가능성이 클 것으로 전망된다. 바나나껍질 추출물은 합성인디고 환원에 효과적이었다. 인디고 환원은 바나나껍질 추출물을 첨가하면서 바로 시작되고, 24시간 경과 후 최대 염착량과 최고 전압값을 나타냈다. 바나나 껍질 추출물의 농도가 높아질수록 인디고 환원력은 높아지고 염착량도 증가하는 것으로 나타났다. 따라서 바나나 껍질 추출물은 인디고 환원에서 화학물질인 하이드로설파이트를 대체하여 사용할 수 있는 효과적인 천연유기환원제로 사용할 수 있을 것으로 기대된다.