• 제목/요약/키워드: Compaction effect

검색결과 404건 처리시간 0.031초

CGS공법에 의한 해성점토 및 준설매립지반의 기초보강 사례 (Case Study for Improvement of Marine Clay and Dredgedfill Ground by CGS Method)

  • 신은철;정덕교;서귀창;이명신
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2010년도 춘계 학술발표회
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    • pp.480-488
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    • 2010
  • The CGS method is non-discharge replacement method improving ground stiffness by the effect of static compaction with injecting very low slump mortar into ground, and is applied for increasing bearing capacity and filling ground cavity by lifting or restoring differential settled structures and preventing differential settlement. This paper suggests design of ground improvement and construction case history for civil engineering structures by CGS method. This method can be used for reinforcing soft ground and liquefaction of loose sandy soil. This method was used in SongDo area in Incheon Economic Free Zone due to its low vibration of ground while it can improve the soft soil where underground structures(subway and box culvert) are already existed.

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파쇄된 발포폴리스티렌을 이용한 경량혼합토의 다짐특성 (Compaction Propertiesof Light Weight Soil Mixtures Using Crushed Expanded Polystyrene)

  • 강성;장병욱
    • 한국농공학회지
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    • 제41권1호
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    • pp.79-85
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    • 1999
  • Use of soils with crushed expanded polystyrene(EPS) satisfied both recycling of industrial waste and development of new light-weight fill materials. Objectives of the study were to make the mixed the mixed soils with the crushed EPS and to suggest the most rational mixing ration as a fill material. A series of laboratory tests was performed to investigate the relationship between miximum dry density and optimum moisture contenr and to find the variation of CBR for mixtures with 3 soils and 2 sizes of the crushed EPS. Results of the test showed that the sizes fo the curshed EPS had a little effect on the properties of mixed soils. But gradatiion of soils and mixing ration with the crushed EPS were important factors to characterize compaction properties of the mixed soils.

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Computational Analysis of Impulse Forces Affecting Coil Compaction in Cerebral Aneurysms

  • Cha Kyung-Se;Balaras Elias
    • 대한의용생체공학회:의공학회지
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    • 제27권3호
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    • pp.94-100
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    • 2006
  • The effectiveness of the treatment of intracranial aneurysms with endovascular coiling depends on coil packing density, the location of aneurysm, its neck dimensions with respect to the aneurysm dome, and its size with respect to the surrounding tissue. Clinical data also suggests that the aneurysm neck size is the main predictor of aneurysm recanalization. In this study, the force impinging on the aneurysm neck in an idealized aneurysm was calculated by using a three dimensional finite volume method for the non-Newtonian incompressible laminar flow. To quantify the effect of neck size on the impingement force, calculations were performed for aneurysm neck diameters (Da) varying from 10% to 100% of the parent artery diameter (Dp). Also, maximum impingement forces were represented by a function of the ratio of the aneurysm neck to the diameter of the parent vessel. The results show that the hemodynamic forces exerted on the coil mass at the aneurysm neck due to the pulsatile blood flow are larger for wide necked aneurysms.

순환골재 다공질 콘크리트 말뚝에 의한 복합지반의 침하 거동 (Settlement Behavior of Composition Ground Improved by Recycled-Aggregate Porous Concrete Pile)

  • 김세원;유승경;이창민;조성민;심민보;최항석
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2008년도 추계 학술발표회
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    • pp.1623-1629
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    • 2008
  • The purpose of this research is to assess the application of recycled-aggregate that is gained from construction wastes as the material of compaction pile method. At the same time, the development of the new technique rectifies defects of the existing compaction pile method for soft ground improvement. In this research, model tests were conducted for analyzing the effect of the soft ground improvement by porous concrete pile using recycled aggregate. Through the results of the model tests, the behavior of settlement on composition ground with surcharge pressure were elucidated.

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Warm Compression of Al Alloy PM Blends

  • Jiang, Z.;Falticeanu, C.L.;Chang, I.T.H.
    • 한국분말야금학회:학술대회논문집
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    • 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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    • pp.193-194
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    • 2006
  • With the onging trend of weight saving in automobiles, the application of light alloys is increasing. Recently, aluminum powder metallurgy has been the subject of renewed attention due to the combination of lightweight of aluminium and the efficient material utilisation of the powder metallurgical process, which offer attractive benefits to potential end-users. This study is to explore the use of warm compaction process to aluminium powder metallurgy. This paper presents a detailed study of the effect of warm compression and sintering conditions on the resultant microstructures and mechanical properties of Al-Cu-Mg-Si PM blend.

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P/M법과 유도가열 공정을 이용한 발포용 6061 Al 합금 프리커서 제조 (Fabrication of Al 6061 Foamable Precursor by Powder Metallurgical and Induction Heating Method)

  • 윤성원;강충길
    • 소성∙가공
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    • 제12권5호
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    • pp.457-464
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    • 2003
  • In the powder compact melting technique, proper precursor fabrication is very important because density distribution after foaming and foamability are determined during precursor fabrication process. The fabrication of the precursor has to be performed very carefully because any residual porosity or other defects will lead to poor results in further processing. In order to evaluate the effect of the compaction parameters on the kinetics of the foaming process, a series of experiments were performed. In this study, aluminium foams with a closed cell structure were fabricated by using both the powder compact method and the induction heating process. A proper induction coil was designed to obtain a uniform temperature distribution over the entire cross sectional area of precursor. To establish the foamable precursor fabrication conditions, effects of process parameters such as the titanium hydride content (0.3∼1.5 wt.%), pressing pressure of the foamable precursor (50∼150kN) on the pore morphology were investigated.

수소 환원 온도에 따른 몰리브덴 산화물의 성형 및 상압소결특성 평가 (Characterization of Compacted and Pressureless Sintered Parts for Molybdenum Oxide Powder according to Hydrogen Reduction Temperature)

  • 이종훈;이근재
    • 한국분말재료학회지
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    • 제31권4호
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    • pp.336-341
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    • 2024
  • Molybdenum, valued for its high melting point and exceptional physical and chemical properties, is studied in diverse fields such as electronics, petrochemicals, and aviation. Among molybdenum oxides, molybdenum dioxide stands out for its higher electrical conductivity than other transition metal oxides due to its structural characteristics, exhibiting metallic properties. It is applied as pellets to gas sensors, semiconductors, and secondary batteries for its properties. Thus, research on molybdenum dioxide compaction and pressureless sintering is necessary, yet research on pressureless sintering is currently insufficient. This study synthesized MoO3 powder via solution combustion synthesis and reduced it using the 3% hydrogen/argon gas mixture to investigate the effect of reduction temperature on the powder. Additionally, the reduced powder was compacted and subjected to pressureless sintering with temperature as a variable. The density and the microstructure of brown parts were analyzed and discussed.

콘크리트 충전상태에 따른 보부재의 휨거동에 관한 연구 (Effect of Concrete Filling Conditions on Flexural Behavior of Beam Members)

  • 장일영;윤영수;노병철;박훈규
    • 콘크리트학회논문집
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    • 제12권2호
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    • pp.3-11
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    • 2000
  • There is a possibility of poor-state concrete filling condition due to segregation and interlocking of aggregate and paste when a high performance concrete is used at reinforced concrete structure without compaction. This study was conducted to evaluate the flexural behavior of high performance concrete beams with design parameters such as c, t and different concrete filling conditions. Different concrete filling conditions were intentionally made such that the first type specimen was soundly cast to obtain the perfect concrete filling condition. Second type was cast in such a way that up to the longitudinal tensile reinforcement from the top, good concrete was filled while poor concrete was poured for the bottom part to simulate the poor strength, workability and unsatisfactory compaction. Third type was cast in such a was that up to the neutral axis of the beam section from the top, good concrete was filled while so did for the bottom part as the second type. The test results were analyzed in terms of load-displacement response, failure pattern, crack width and crack spacing. The test results indicate that have no effect of concrete filling conditions on the yielding strength of structures. But, have a grate influence on the stiffness and ductility of structures.