• Title/Summary/Keyword: Expanded metal

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Adsorption property of heavy metals onto MCM-41 and expanded graphite (MCM-41 및 팽창흑연의 중금속 흡착특성)

  • Lee, Myoung-Eun;Lee, Chae-Young;Kang, Seok-Tae;Kim, Sang-Hyoun;Cho, Yun-Chul;Kim, Soo-Hong;Chung, Jae-Woo
    • Journal of Korean Society of Water and Wastewater
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    • v.26 no.2
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    • pp.275-283
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    • 2012
  • MCM-41(Mobil's Composition of Matter-41) and expanded graphite(EG) were investigated as potential adsorbents for heavy metal ions including Pb(II), Cu(II) and Ni(II) in various aqueous chemistries. MCM-41 showed shorter equilibrium times and higher adsorption capacities for all three heavy metal ions compared to expanded graphite. The adsorption of three heavy metal ions was significantly affected by the solution pH due to the competition with $H_{3}O^{+}$ at lower pH and precipitation at neutral or higher pH. Adsorptions of heavy metal ions onto MCM-41 and expanded graphite were successfully described with the pseudo-second-order model. During the competitive adsorption of three heavy metal ions, the selectivity of Pb(II) was highest and almost same selectivity was observed with Cu(II) and Ni(II) when MCM-41 was used as an adsorbent, while the expanded graphite exhibited the highest selectivity to Pb(II), followed by Ni(II) and Cu(II).

A Study on the Properties comparison of the PVC Net and Expanded Metal Using Rockfall Protection Net Pullout Test Equipment (낙석방지망 인발시험을 이용한 PVC망과 Expanded Metal 특성비교에 관한 연구)

  • Cheon, Seongyeol;Lee, Seungho
    • Journal of the Korean GEO-environmental Society
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    • v.10 no.4
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    • pp.49-57
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    • 2009
  • The governmental investment to SOC facilities currently has increasedthe construction of new roads and the consistent extension of already-existing roads or the line-shape revision of those roads. As a result, the road cut slopes have been increasingrapidly. Unfortunately, human-life damages and property damages frequently occur due to the rockfall and the landslide every year. To reduce those damages, many studies have been performed. The present regulation regarding rockfall protection facilities follows the "Guide for Installation and Management of Road Safety Facilities" issued by MLTM (the Ministry of Land, Transport, and Maritime Affairs) that indicates the standard size of facilities and energy absorbing efficiencies. Most domestic road slopes use standardized rockfall protection facilities based on the regulation. However, there have been doubted about the effectiveness of rockfall protection facilities and the damages caused by rockfalls havebeen increasedevery year. Thus, it seems that relevant studies are necessary on the rockfall protection net being capable of supporting rockfall energies. Accordingly, this study reviews previous literature to investigate the function and the feature of rockfall protection nets and analyzetheir limitations by each type. After that, by using the pullout test device for a rockfall protection net, an experiment on the PVC coating net and the expanded metal is performed under the exact same condition. Finally, the features of the Expended metal is explained with the comparison analysises of load-variation and the confirmation of damaged forms. As a result, there have been founded the problemsof net breaking down and not being able to support due to PVC coating net's material property of disintegration. On the other hand, the Expanded Metal might be expected as a substituteof rockfall protection net according to its capability of support and integration.

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Investigation into characteristics of bending stiffness and failure for ISB panel (ISB 판넬의 굽힘강성 및 파단특성에 관한 연구)

  • 안동규;이상훈;김민수;한길영;정창균;양동열
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2004.10a
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    • pp.1274-1277
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    • 2004
  • The objective of this research work is to investigate into characteristics of bending stiffness and failure for the ISB ultra-lightweight panel with internally structured material. The expanded metal with a pyramid shape and woven metal are employed as an internally structured material. In order to investigate the characteristics, the specific stiffness and failure map are estimated using the results of three-points bending test. From the results of the experiment, the influence of design parameters of ISB panel on the specific stiffness and failure mode has been found. In addition, it has been shown that ISB panel with expanded metal is prefer to that with woven metal from the view point of optimal design for ISB panel.

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Bending Behaviour of Composite Slab Using a New-Shaped Steel Deck Plate and Expanded Metal (신형 데크플레이트와 철판망을 적용한 합성슬래브의 휨 거동)

  • Kim, Myoung Mo;Eom, Chul Hwan
    • Journal of Korean Society of Steel Construction
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    • v.15 no.4 s.65
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    • pp.403-412
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    • 2003
  • The composite metal deck plate system has been widely used for office structures. Recently, however, the flat deck plate has been developed to apply the composite slab system to residential structures. Reduction in construction cost and time can be expected by using expanded metal instead of wire mesh as crack control reinforcements. This study proposed a composite slab system composed of a new-shaped steel deck plate and expanded metal. Twelve specimens were tested to evaluate the structural performance of the new composite slab system. The test results were summarized mainly in terms of maximum load carrying capacity and failure behaviors of each specimen.

Mechanical Behavior of Sandwich Panels with Quasi-Kagome Truss Core Fabricated from Expanded Metals (확장금속망을 이용하여 제작된 준카고메 트러스 중간층을 갖는 샌드위치 판재의 기계적 거동)

  • Lim, Chae-Hong;Lim, Ji-Hyun;Jung, Jae-Gyu;Lim, Jong-Dae;Kang, Ki-Ju
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.30 no.9 s.252
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    • pp.1078-1085
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    • 2006
  • Many studies have been focused on how to manufacture ultra light metal structures and optimize them. In this study, we introduced a new idea to make sandwich panels with quasi-Kagome truss cores. First, metal sheets with a peculiar pattern of slits were expanded to be meshes, they are crimped into a triangular wave pattern, and then one third of struts were bent reversely to be quasi-Kagome trusses. Finally, two face sheets were bonded on the upper and the lower sides. The bending strength was estimated through elementary mechanics for the sandwich specimens with two kinds of face sheet the results of estimation were compared with the those of finite element analyses and experiments.

A Study on the Shear Deformation Behavior of Inner Structure-Bonded Sheet Metal (접합판재의 전단 변형거동에 관한 연구)

  • Kim J. Y.;Chung W. J.;Yang D. Y.;Kim J. H.
    • Transactions of Materials Processing
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    • v.14 no.3 s.75
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    • pp.257-262
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    • 2005
  • In order to improve the quality of the sheared surface in cutting of inner structure bonded sheet metal the cut-off operation is mainly investigated, which is the typical shearing process in sheet metal forming technology. The sandwich sheet metals considered have inner structure which is constructed in the form of crimped expanded metal and woven metal. The inner structure is bonded between solid sheet by resistance welding or adhesive bonding. The shearing process is visualized by the computer vision system installed in front of the cut-off die and the sheared surface is measured and quantitatively compared with the help of the optical microscope after cut-off operation. From test results we found that the influence of sheared position can be observed and explained clearly and this result can be utilized to get the better sheared surface.

A Study on the Shear Deformation Behavior of Inner Structure-Bonded sheet metal (접합판재의 전단 변형거동에 관한 연구)

  • Kim J. Y.;Kim J. H.;Chung W. J.;Yang D. Y.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2004.11a
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    • pp.33-38
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    • 2004
  • In order to improve the quality of the sheared surface in cutting of inner structure bonded sheet metal the cut-off operation is mainly investigated, which is the typical shearing process in sheet metal forming technology. The sandwich sheet metals considered have inner structure which is constructed in the form of crimped expanded metal and woven metal. The inner structure is bonded between solid sheet by resistance welding or adhesive bonding. The shearing process is visualized by the computer vision system installed in front of the cut-off die and the sheared surface is measured and quantitatively compared with the help of the optical microscope after cut-off operation. From test results we found that the influence of sheared position can be observed and explained clearly and this result can be utilized to get the better sheared surface.

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A Study on Protection Depending on Mesh Size of Expanded Metal for Slope Reinforcement (사면보강용 Expanded Metal 격자크기에 따른 인발 특성 연구)

  • Ji, Younghwan;Kim, Kihwan;Kim, Sungho;Hwang, Yeongcheol;Lee, Seungho
    • Journal of the Korean GEO-environmental Society
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    • v.11 no.12
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    • pp.47-56
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    • 2010
  • The construction of new roads and the consistent extension of already-existing roads or the line-shape revision of those roads are increased with the governmental investment to SOC facilities currently. Accordingly, the road cut slopes are in the trend of rapidly increasing. As the road slope has increased, a lot of human and property damages has entailed consequently and in the local case, numerous studies have carried out aiming at minimizing this damages caused by the rockfall and landslide. In general, standard falling rock prevention facility has employed for most of the local road slope based on "Guide for Installation and Management of Road Safety Facilities" published by MLTM(the Ministry of Land, Transport, and Maritime Affairs) but profound doubt has raised as to whether this rockfall prevention facility would function properly enough to prevent rockfall efficiently without any damages in case of actual occurrence of rockfall. In addition, it is a reality that in most cases, such work is relied on overseas technology as a whole as the local technical level is low and in case of rockfall prevention net, it is judged that a study on rockfall prevention net that is able to endure more powerful rockfall energy is required as the problem including net bursting is taken place as a result of enough bearing force being failed to be demonstrated due to its partial weak point(not uniformly made). Under this background, in this study, three kinds of model depending on mesh size of expanded metal that is considered to have an adoptability as rockfall prevention net, as target are selected and characteristics depending on mesh size of expanded metal is intended to be researched through a pull-out test performance by using pull-out test equipment rockfall prevention net.

Investigation into static and dynamic characteristics of ISB panels with the expanded metal as an internally structured material (익스펜디드 금속을 내부 구조체로 가지는 ISB 판넬의 정적.동적 특성 분석)

  • Ahn D.G.;Lee S.H.;Kim M.S.;Hahn G.Y.;Jung C.G.;Yang D.Y.
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2005.06a
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    • pp.832-835
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    • 2005
  • The objective of this research work is to investigate into static and dynamic characteristics of ISB panels with the expanded metal as an internally structured material. In order to investigate static and dynamic characteristics of ISB panels, several experiments, the tensile test, three-point bending test and impact test, are carried out. From the results of the experiments, the mechanical properties, bending stiffness and impact absorption energy of the ISB panel have been obtained. In addition, it has been shown that the static and dynamic characteristics of ISB panel are highly dependent on the crimping angle of the pyramidal structure for the expanded metal.

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