• 제목/요약/키워드: stone

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석재(石材) 가공(加工)시 발생한 석분(石粉)이 혼합된 콘크리트의 압축강도(壓縮强度) 특성(特性)에 관한 연구 (A Study on the Concrete Compressive Strength Characteristics mixing Stone Dust Produced by Stone Block Manufacturing)

  • 채영석;민인기;송갑용
    • 자원리싸이클링
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    • 제18권6호
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    • pp.46-53
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    • 2009
  • 석재 가공 시 발생되는 석분은 산업폐기물로 되어있다. 현재 이 석분은 지하에 매립하거나 지상에 야적되어 방치되고 있어 폐기물로 처리하는 데 많은 비용이 요구되고 있고, 토질과 지하수 등의 환경오염의 원인이 되고 있다. 또한 콘크리트의 주재료인 골재의 공급이 부족한 현실을 고려하여 본 연구에서는 폐석분을 콘크리트 혼화재료로 재활용할 수 있는 가능성을 연구하고자 한다. 석분함유량에 대한 시멘트비를 조정한 결과, $20{\sim}30\;N/mm^2$의 콘크리트의 압축강도가 나타났고 이는 석분의 함유에 따라 압축강도가 감소되지 않음을 알 수 있었다. 석재 가공 시 발생되는 석분을 콘크리트 혼화재료로 재순환하여 사용하여도 콘크리트의 압축강도에는 전혀 문제가 없음을 알 수 있었다.

폐석 및 석분 슬러지를 활용한 인조석판재의 제조 (Manufacture of Artificial stone using Wasts Stone and Powder Sludge)

  • 손정수;김병규;김치권
    • 자원리싸이클링
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    • 제4권1호
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    • pp.4-11
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    • 1995
  • 국내 각 채석장 및 석재 가공공정에서 발생되는 폐석과 석분 슬러지를 활용하여 장식재, 바닥재 및 내외장재 등에 쓰이는 인조 석판재 제조기술을 개발하고자 하였다. 인조석재는 폐석과 결합제 및 경화제 등을 혼합하여 제조하였으며 성형압력, 폐석 및 석분 슬러지의 결합비 그리고 결합제의 양 등의 변화에 따른 인조석재 각각의 특성을 비교하였다. 천연석재와 인조석재와의 물성을 비교하기 위하여 $\circled1$ 비중,$\circled2$ 흡수율, $\circled3$ 탄성파속도, $\circled4$ 압축강도, $\circled5$ 인장강도, $\circled6$ 반발경도, $\circled7$ 탄성계수 $\circled8$ 포아송비를 측정하였으며 $\circled9$ 내열성도 함께 조사하였는데 석재의 물성은 원료의 혼합정도, 성형압력 및 결합제의 양에 의해 좌우됨을 알 수 있었다. 본 인조석재의 제조에도 석분에 비해 고가인 결합제의 사용을 가능한한 최소로 하여 폐기물로 배출되는 폐석 및 석분슬러지를 최대한 활용할 수 있도록 하였으며 성형압력 $200kg/\textrm{cm}^2$, 결합제의 양 12~15wt.%의 제조조건에서 원하는 물성을 갖는 인조석재를 제조할 수 있었다.

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3D seismic assessment of historical stone arch bridges considering effects of normal-shear directions of stiffness parameters between discrete stone elements

  • Cavuslu, Murat
    • Structural Engineering and Mechanics
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    • 제83권2호
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    • pp.207-227
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    • 2022
  • In general, the interaction conditions between the discrete stones are not taken into account by structural engineers during the modeling and analyzing of historical stone bridges. However, many structural damages in the stone bridges occur due to ignoring the interaction conditions between discrete stones. In this study, it is aimed to examine the seismic behavior of a historical stone bridge by considering the interaction stiffness parameters between stone elements. For this purpose, Tokatli historical stone arch bridge was built in 1179 in Karabük-Turkey, is chosen for three-dimensional (3D) seismic analyses. Firstly, the 3D finite-difference model of the Tokatli stone bridge is created using the FLAC3D software. During the modeling processes, the Burger-Creep material model which was not used to examine the seismic behavior of historical stone bridges in the past is utilized. Furthermore, the free-field and quiet non-reflecting boundary conditions are defined to the lateral and bottom boundaries of the bridge. Thanks to these boundary conditions, earthquake waves do not reflect in the 3D model. After each stone element is modeled separately, stiffness elements are defined between the stone elements. Three situations of the stiffness elements are considered in the seismic analyses; a) for only normal direction b) for only shear direction c) for both normal and shear directions. The earthquake analyses of the bridge are performed for these three different situations of the bridge. The far-fault and near-fault conditions of 1989 Loma Prieta earthquake are taken into account during the earthquake analyses. According to the seismic analysis results, the directions of the stiffness parameters seriously changed the earthquake behavior of the Tokatli bridge. Moreover, the most critical stiffness parameter is determined for seismic analyses of historical stone arch bridges.

서산보원사법인국사보승탑 해체복원을 통해 살펴 본 석조문화재의 보존 (Conservation of stone cultural properties-Restoration and Conservation Treatment about Bowonsabeobin-guksaboseungtap(Stupa of high priest Beobinguksa of Bowonsa Temple))

  • 신은정;김사덕
    • 보존과학연구
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    • 통권25호
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    • pp.93-117
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    • 2004
  • The stone cultural properties durability is the falling. So the conservation is easy relatively. But the conservation countermeasure of the stone cultural properties the environment pollution needed urgently as extreme. I will find out about the stone cultural properties Through the example of Restoration and conservation treatment about Bowonsabeobin-guksaboseungtap in the paper. Damage reasons of the stone cultural properties are a physical damage, a structural damage, a biology damage, a chemical damage and artificial damage. The moisture plays especially the role which damage is make the stone cultural properties. The stone cultural properties is damaged due to damage reasons. So we investigate the stone cultural properties and must remove damage reasons. Bowonsabeobin-guksaboseungtap is funerary stupa of buddhist monk with circleorientedoctagon in Geryeo Period. There is the open air. Parts of it were damaged by grave robbery in 2004. So restoration was begun in 2004.While restoring it, wrong arrangement on top of the monk-stupa was rearranged. After being arranged in right order, the middle of monk-stupa was fixed by setting up stainlesssteel shaft. A roof stone of stupa finial has cracks. So It was adhered with epoxy resin(L-30) and was washed with distilled water for pollution clearing. The stone cultural properties takes the influence of the environment pollution much because it stays at the fields. It is easy also to be robed. Therefore we must watch more with the concern.

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한국(韓國) 고대(古代) 대조건축(大造建築) 구조(構造)의 추정(推定)에 관(關)한 연구(硏究) -석탑(石塔)의 건축요소(建築要素) 분석(分析)을 중심(中心)으로- (A Study on the Architectural Structure of Ancient Korean Wooden Buildings - Focused on the Analysis of the Architectural Elements of Stone Pagoads -)

  • 박재평;이재현
    • 한국농촌건축학회논문집
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    • 제4권1호
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    • pp.71-86
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    • 2002
  • This research aims to illustrate the structure of the ancient Korean wooden buildings by a comparative study of the historical resources such as stone remains, wall paintings historiographies and excavations. As stone pagodas are the most typical stone remains, I selected for analysis some stone pagodas which contain architectural elements and results of the study are as follows: 1) The number of stories and structural modes of the base stone part show the wooden architectural aspects: they have one or two stories and their base part is constructed in the mode of assembling rectangular stones. 2) The body of the pagoda contains such architectural elements as pillars, door and windows, crossbeams, balcony, bracket sets. 3) The roof of the stone pagoda contains such architectural elements as eaves, roofs and modes of stone assembling. The results inferred through this research could be of help for further comparative studies with the other secondary materials by providing basic knowledge for it.

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Evaluation of monotonic and cyclic behaviour of geotextile encased stone columns

  • Ardakani, Alireza;Gholampoor, Naeem;Bayat, Mahdi;Bayat, Mahmoud
    • Structural Engineering and Mechanics
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    • 제65권1호
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    • pp.81-89
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    • 2018
  • Stone column installation is a convenient method for improvement of soft ground. In very soft clays, in order to increase the lateral confinement of the stone columns, encasing the columns with high stiffness and creep resistant geosynthetics has proved to be a successful solution. This paper presents the results of three dimensional finite element analyses for evaluating improvement in behaviour of ordinary stone columns (OSCs) installed in soft clay by geotextile encasement under monotonic and cyclic loading by a comprehensive parametric study. The parameters include length and stiffness of encasement, types of stone columns (floating and end bearing), frictional angle and elastic modulus of stone column's material and diameter of stone columns. The results indicate that increasing the stiffness of encasement clearly enhances cyclic behaviour of geotextile encased stone columns (GESCs) in terms of reduction in residual settlement. Performance of GESCs is less sensitive to internal friction angle and elasticity modulus of column's materials in comparison with OSCs. Also, encasing at the top portion of stone column up to triple the diameter of column is found to be adequate in improving its residual settlement and at all loading cycles, end bearing columns provide much higher resistance than floating columns.

석탑구조물의 표면거칠기 및 충전재에 따른 석재접촉면의 구조특성 분석 (Structural Characteristics Analysis of Stone Contact Surface according to Surface Roughness and Filling Material of Stone Pagoda Structure)

  • 김호수;김동관;이승희;김덕문;조상순
    • 대한건축학회논문집:구조계
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    • 제34권6호
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    • pp.19-27
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    • 2018
  • The stone pagoda structure is treated as a discontinuous masonry structure, and the contact surface characteristics between stones is a very important factor in the discontinuum behavior analysis. So, it is necessary to find out material and structural characteristics of stone contact surface to perform the structural analysis for safety evaluation. Accordingly, it is important to analyze the material properties of stone surface and secure the structural characteristics through various contact surface states. Therefore, in this study, various test specimens applying the filler between the surface roughness and the stone in the contact surface treatment technique of the stone pagoda were manufactured, and compression test and shear test were carried out. Also, we analyzed the material and structural characteristics of the stone contact surface through the comparison of experimental results.

청바지의 세탁가공에 관한 연구(I) -세탁가공의 종류를 중심으로- (The Washing Finish of Blue Jeans(I) - the comparison of neutral cellulase, acid cellulase, stone, and stone-neutral cellulase washings -)

  • 신혜원;유효선
    • 한국의류학회지
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    • 제21권2호
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    • pp.471-481
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    • 1997
  • Denims were treated with neutral cellulase, acid cellulase, stone, and stone-neutral cellulase respectively at different cellulase concentrations varying treatment times in rotary washer. The effect of washing on denim was estimated by the changes in weight, color, back staining, tear strength, flex stiffness, and surface characteristics. Also the comparison of neutral cellulase, acid cellulase, stone, and stone-neutral cellulase washings was studied. Washing removes surface fibers and provides weight loss, color difference, back staining, and a decrease in tear strength and in flex stiffness. Stone-neutral cellulase washing and acid cellulase washing have a larger washing effect than neutral cellulase washing and stone washing.

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<홍정명 지석>에 관한 연구 (A Study on the Stone Epitaph of Hong Jeong-Myeong)

  • 박문열
    • 한국도서관정보학회지
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    • 제35권1호
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    • pp.135-154
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    • 2004
  • This study is a physical and textual analysis on an epigraph, the Stone Epitaph of Hong Jeong-Myeong(홍정명 지석). This was edited by Lee Deuk-Sin and transcribed by Gang Se-Hwang. On the view of physical point the Stone Epitagh is made of black stone and its size is 27.8∼28.2cm high, 20.3∼20.7cm wide, and 2.0∼3.6cm thick. On the view of textual point, the text of Stone Epitaph is about the career of Hong Jeong-Myeong, and the printed style of writing is by depressed engraving on 8 black stone plane.

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제주 전통돌담의 유지보전에 관한 의식조사 (A Survey on Preservation of Traditional Stone Fences in Jeju)

  • 이상영
    • 농촌계획
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    • 제13권1호
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    • pp.33-40
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    • 2007
  • The purpose of this paper is to analyze the value of stone fences in Jeju Island. The result that executes attitude survey to local resident and visitor can be summarizing as following. First are the function and the value of Jeju traditional stone fences. Local resident favored the culture heritage succession and evaluated its' usage Value highly. Visitors also have favored rural landscape offer function and evaluated inheritance value (Bequest Value) highly. Secondly, 80.5% of visitors, 78.1% of local resident have formed opinion about preservation of traditional stone fences. But the Willingness to pay for traditional stone fences fund was raised by 38.6% in local resident and 55.7% in visitor. The reason that willingness to pay does not exist is that it is chargeable to connection group and government, or it has no money to pay. Thirdly, local resident wanted to use made up stone fence preservation fund in rural landscape offer function. Visitor wanted that it is used to raise various function of stone fence.