• Title/Summary/Keyword: construction disposal

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Effect of crushed waste glass as partial replacement of natural fine aggregate on performance of high strength cement concrete

  • Ajmal, Paktiawal;Mehtab, Alam
    • Advances in materials Research
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    • v.11 no.4
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    • pp.251-277
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    • 2022
  • Disposal of industrial waste in cities where municipal authorities permitting higher floor area ratio coupled with increasing living standards, a lot of demolition waste is being generated. Its disposal is a challenge particularly in megacities where no landfills are available. The ever-increasing cost of building construction materials also necessitates consuming demolition wastes in a useful manner to save fresh natural raw materials. In the present work, the crushed waste glass is used in high-strength concrete as a partial replacement of fine aggregate. The control concrete of grade M60 was proportioned following BIS 10262-2009. The crushed waste glass has been used as a partial replacement with varying percentages of 10, 20, 30, and 40% by weight of fine aggregate. Experimental tests were carried on the fresh and hardened state of the concrete. The effect of crushed waste glass on the workability of the concrete has been investigated. Non-destructive tests, acid attack tests, compressive strength, split tensile strength, and X-ray diffraction analysis was carried out for the control concrete and concrete containing crushed waste glass after 7, 28, and 270 days of normal curing. The results show that for the same w/c ratio, the workability of concrete increases with increasing replaced crushed waste glass content. However, the decrease in compressive strength of the concrete after 28 days of normal curing and further after 28 days of acid attacks, up to 30% replacement level of fine aggregate by the crushed waste glass is insignificant.

A Study on Management Status of Disposed FRP Fishing Boats and Competitive Advantages of Third Recycling Technology (FRP 폐어선 관리 실태와 재활용 기술 경쟁우위에 관한 연구)

  • Dong-Hun Go;Yeong-Tae Son
    • The Journal of Fisheries Business Administration
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    • v.54 no.3
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    • pp.93-114
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    • 2023
  • Around the 1980s, with government's promotion and dissemination policies for FRP (Fiberglass Reinforced Plastics) of the government as a main material of fishing boats, approximately 97% of the entire fishing boats in Korea have utilized FRP until now. Nevertheless, diverse social and environmental issues have emerged due to the susceptibility to fire and the generation of substances detrimental to human health during the construction process of FRP fishing vessels. Especially, the high disposal cost and the limitation of recycling technology in the disposal process of FRP fishing boats have elicited attention to circular economy. This research intended to grasp the management status and problems of disposed FRP fishing boats in Korea, and to assess the level of competitive advantage of FRP fishing boats' recycling technologies of FRP fishing boats based on VRIO (Value, Rarity, Imitability, Organization) analysis through domestic and foreign management policies and related recycling examples. According to the survey of 161 respondents, including the industry, stakeholders and experts related to the collection, treatment and recycling of fisheries wastes, it was revealed that FRP fishing boats' recycling technologies of FRP fishing boats are at the level of 'unused competitive advantage' that satisfied the level of value, rarity and imitability, but not the level of organization.

A Study on the Construction of Cutting Scenario for Kori Unit 1 Bio-shield considering ALARA

  • Hak-Yun Lee;Min-Ho Lee;Ki-Tae Yang;Jun-Yeol An;Jong-Soon Song
    • Nuclear Engineering and Technology
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    • v.55 no.11
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    • pp.4181-4190
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    • 2023
  • Nuclear power plants are subjected to various processes during decommissioning, including cutting, decontamination, disposal, and treatment. The cutting of massive bio-shields is a significant step in the decommissioning process. Cutting is performed near the target structure, and during this process, workers are exposed to potential radioactive elements. However, studies considering worker exposure management during such cutting operations are limited. Furthermore, dismantling a nuclear power plant under certain circumstances may result in the unnecessary radiation exposure of workers and an increase in secondary waste generation. In this study, a cutting scenario was formulated considering the bio-shield as a representative structure. The specifications of a standard South Korean radioactive waste disposal drum were used as the basic conditions. Additionally, we explored the hot-to-cold and cold-to-hot methods, with and without the application of polishing during decontamination. For evaluating various scenarios, different cutting time points up to 30 years after permanent shutdown were considered, and cutting speeds of 1-10nullm2/h were applied to account for the variability and uncertainty attributable to the design output and specifications. The obtained results provide fundamental guidelines for establishing cutting methods suitable for large structures.

A Study on the Estimation about Aomunt of the Amelioration Districts for Optimum Process of Designated Wastes (적정처리를 위한 주거환경개선지구 내 구조형태별 지정폐기물 발생량 예측에 관한 연구)

  • Shin, Yong-Chul;Son, Byeung-Hun;Hong, Won-Hwa;Lee, Jae-Sung
    • Proceeding of Spring/Autumn Annual Conference of KHA
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    • 2008.04a
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    • pp.285-290
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    • 2008
  • Recently, the scale of the construction work has been increased due to the revitalization of the construction industries. therefore, the demolition work in downtown areas is increased too. Amelioration districts are deteriorating rapidly since it followed the policy which allowed a large number of constructions in a very short period of time. therefore, the quantity of construction wastes and the designated wastes such as asbestos are increased. This study was classifying and analyzing the constructions in amelioration districts to estimate quantity of the designated wastes and the unit of the designated wastes. According to the results of this research, the average annual designated wastes was increased up to 2.59% in comparison with 2,779,334 ton in 2000, there came out 3,151,653 ton of designated wastes in 2005. For the appropriate disposal of increasing designated wastes, it is necessary to study exact estimation of the quantity of wastes.

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Durability characteristics of recycled aggregate concrete

  • Saravanakumar, Palaniraj;Dhinakaran, Govindasamy
    • Structural Engineering and Mechanics
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    • v.47 no.5
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    • pp.701-711
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    • 2013
  • People started to replace natural aggregate with recycled aggregate for a number of years due to disposal problem and certain other potential benefits. Though there are number of drawbacks with use of recycled aggregates like lesser modulus of elasticity, low compressive strength, increase in shrinkage, there are results of earlier studies that use of chemical and mineral admixtures improves the strength and durability of recycled concrete. The use of recycled aggregate from construction and demolition wastes is showing prospective application in construction as alternative to natural aggregates. It conserves lot of natural resources and reduces the space required for the landfill disposal. In the present research work, the effect of recycled aggregate on strength and durability aspects of concrete is studied. Grade of concrete chosen for the present work is M50 (with a characteristic compressive strength of 50 MPa). The recycled aggregates were collected from demolished structure with 20 years of age. Natural Aggregate (NA) was replaced with Recycled Aggregate (RA) in different percentages such as 25, 50 and 100 to understand its effect. The experiments were conducted for different ages of concrete such as 7, 14, 28, 56 days to assess the compressive and tensile strength. Durability characteristics of recycled aggregate concrete were studied with Rapid chloride penetration test (as per ASTMC1202), sorptivity test and acid test to assess resistance against chloride ion penetration, capillary suction and chemical attack respectively. Mix design for 50 MPa gives around 35 MPa after replacing natural aggregate with recycled aggregate in concrete mix and the chloride penetration range also lies in moderate limit. Hence it is understood from the results that replacement of NA with RA is very much possible and will be ecofriendly.

A Study on Extension of Application of Industrial By-products: Strength Characteristics of Shotcrete (산업부산물의 사용성 확대를 위한 기초연구: 숏크리트의 강도특성)

  • Park, Cheol-Woo;Kwon, Seung-Joon;Sim, Jong-Sung;Kang, Tae-Sung;Lee, Hyeon-Gi;Sim, Jae-Won
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.4 no.3
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    • pp.75-81
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    • 2009
  • The industrial by-products market has increased at a geometric rate worldwide with the rapid economic growth. Among the wide variety of industrial by-products, fly ash which is generated by the combustion of coal is one of the more troublesome industrial wastes because they entail substantial disposal cost and also cause a shortage of disposal sites. In Korea alone, fly ash generation is expected to increase to 5.8 million tons by 2009, and to 6 million tons by 2010. Given the accelerated industrial development in developing countries, the amount of fly ash generation is predicted to reach enormous levels throughout the world. An increasing number of studies have currently focused on the feasibility of recycling industrial wastes i.e., fly ash in terms of environmental advantages. In this study, the optimized mix proportion of high performance shotcrete using fly ash was determined for the purpose of promoting recycling and reuse of resources.

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Recycling Factor Analysis on Wood Wastes in the Construction Site by Classification Origination Reason (건설현장 폐목재의 발생원인 분류를 통한 재활용 요인분석)

  • Jung, Chan-Young;Kim, Jae-Jun;Jung, Young-Gi
    • Korean Journal of Construction Engineering and Management
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    • v.8 no.1 s.35
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    • pp.107-115
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    • 2007
  • Today's human life is more conveniently advantaged and abundant as industrial society advanced. However, the development has been creating a serious environmental crisis. Environmental pollution and exhaustion of natural resources recently became an important issue in construction industry as well as the concern about construction waste management and recycling the resources has arisen. Because the industrial wastes are not only increased quantitatively but also qualitatively intricate and various, groping for ways of reducing the use of resources primarily and recycling is urged on promotion. Currently, only about 33% of the wood wastes produced in construction site are recycled and the others are incinerated or disposed through irregular circulation process. In this study, I will investigate the present status of generating, processing, and recycling construction wood wastes and compare domestic disposal trend to other countries. In addition, I will analyze the actual condition of processing wood wastes in the construction site, verify the irrational causes, and simplify anomalous factors for the purpose of more efficient and correct activation of wood waste treatment and recycling on construction field and protection of environment in the long run.

A Study on Application of Dyeing Industrial Heat Source Waste Aggregate as Concrete Aggregate (콘크리트용 굵은 골재로서 염색공단 열원 폐재의 적용성에 관한 연구)

  • Youn, Jang-Kil;Kim, Hyo-Youl;Lim, Nam-Gi
    • Journal of the Korea Institute of Building Construction
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    • v.5 no.1 s.15
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    • pp.123-129
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    • 2005
  • This study is as a part of the new disposal and recycling plans of heat-resource waste of Daegu dyeing industrial center we tried to examine applicable possibility of crushed thing(waste aggregate) as aggregates for mortar and concrete. To examine applicable possibility of waste aggregate as a lightweight-aggregate for concrete and mortar, we carried this study by mainly property examination of concrete according to replacement ratio of waste aggregate. We carried slump, unit weight, compressive strength and bending strength test according to replacement ratio of waste aggregate. As the result of that, if we use waste aggregate, lightweight of concrete and mortar will be possible. Specially it shows a strength improvement effect of cement hardening according to using this so it is judged that applicable possibility as aggregate for concrete and mortar is very excellent.

Study on life cycle of LRT systems and technology development applied system engineering (경량전철 차량시스템 생명주기와 시스템엔지니어링 적용기술개발에 관한 고찰)

  • Lee, Seong-Gwon;Jeon, Seo-Tak;Jung, Kye-Young;Kim, Jae-Jin;Chung, Su-Young
    • Proceedings of the KSR Conference
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    • 2011.05a
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    • pp.1629-1635
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    • 2011
  • Because LRT project is large infrastructure projects investing enormous budget and required continuous maintenance after construction, it is the global trend to perform business in terms of life-cycle from the initial construction, operation to disposal. It is very important LRT to manage interfaces efficiently and to integrate vehicle, civil, track, electricity, communications, signals, operations, facilities organically. Global companies of the railway developed countries including Europe are getting orders a large rail project and preempting the world market based on engineering technology. But, domestic LRT systems engineering is the subcontracting level to the lack of practical skills and experience. Thus, technology securement is very urgent for the independence of systems engineering technology and overseas advance based turnkey. In this paper, we are going to study applicable systems engineering technology focusing on LRT system based on international standard ISO/IEC 15288.

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A Treatment and Construction Use of Municipal Solid Waste Ash (도시고형 폐기물 소각재의 무해화 처리와 응용)

  • Lee, Jae-Jang;Shin, Hee-Duck;Park, Chong-Lyuck
    • Journal of Industrial Technology
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    • v.21 no.B
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    • pp.45-49
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    • 2001
  • Many cities and provinces are rapidly depleting landfill spaces. As the result, some municities have adopted to incinerate their municipal solid waste(MSW). The motive behind the choice is that incineration significantly reduces the volume of solid waste in need of disposal, destroys the harmful organic compounds that are present in MSW, and provides an attractive source of alternative energy. Conclusively, the generation of MSW ash is expected to increse in the furture. However, disposing the MSW ash in landfills may not always be an environmentally or an economically feasible solution. This paper addresses the various issues associated with MSW ash and its possible use in construction applications.

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