• Title/Summary/Keyword: Heaving

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An Experimental Study on Frost Heaving Characteristics of Soil Stabilized with the Additives (안정처리토의 동상특성에 관한 실험적 연구)

  • Kim, Jae-Young;Ju, Jae-Woo;You, Byung-Ok;Yang, Sung-Kee
    • Proceedings of the Korean Society of Agricultural Engineers Conference
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    • 2003.10a
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    • pp.215-218
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    • 2003
  • In order to study the frost heaving characteristics of soil stabilitized with a quick lime, a cement and a briquette ash, frost heaving tests were performed with 2 kinds of soil sampled at Chonbuk-Do area. Frost heaving of no-stabilizing soil compacted with water content greater than optimum water content was increased as the frost period was increased but in case of samples with water content smaller than optimum water content, the frost period gave no affect about increase and decrease of the frost heaving. Both frost heaving of stabilizing and no-stabilizing soil with water content greater than optimum water content was decreased with the increase of the repetition number of freezing and thawing. There was no increase or decrease of frost heaving in the frost heaving test after 5 times of freezing and thawing.

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Experimental Investigation of Frost Heaving Susceptibility with Soils from Terra Nova Bay in Eastern Antarctica (동남극 테라노바만 흙 시료의 동상특성에 관한 실험적 연구)

  • Hong, Seungseo;Park, Junghee;Lee, Jongsub;Lee, Jangguen;Kang, Jaemo;Kim, Youngseok
    • Journal of the Korean GEO-environmental Society
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    • v.13 no.12
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    • pp.5-16
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    • 2012
  • The second scientific antarctic station of South Korea is under construction at Terra Nova Bay located in eastern Antarctica. Ground condition in the Antarctica is frozen in general, but there are seasonal frozen grounds with active layers sporadically. When the active layer is frozen, frost heaving occurs that might cause the differential movement of frozen ground and the failure of structures. Therefore, it is necessary to determine the frost heaving susceptibility of soils at Terra Nova Bay before starting antarctic station construction. This study presents experimental investigation of the frost heaving susceptibility of soil samples with variation of particle sizes and unfrozen water contents. The soil samples were taken from five different locations at Terra Nova Bay and physical properties, unfrozen water content, and frost heaving tests were performed. For the frost heaving tests, soil specimens were frozen with constant freezing temperatures at the top and with drainage at the bottom in order to stimulate the frost heaving. The frost heaving tests provide volume expansion, volumetric strain, and heaving rate which can be used to analyze the relationship between the frost heaving vs. particle size and the frost heaving vs. unfrozen water content. Experimental results show that the more the fine contents exist in soils, the more frost heaving occurs. In addition, the frost heaving depends on unfrozen water content. Experimental data can be used to evaluate the frost heaving susceptibility of soils at the future construction site in the Antarctica.

Evaluation of Ground Water Level Effect on Frost Heaving in Road Pavements (도로 포장체에서 동상에 대한 지하수위 영향 평가)

  • Kweon, Gichul;Lee, Jaehoan
    • International Journal of Highway Engineering
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    • v.15 no.1
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    • pp.47-56
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    • 2013
  • PURPOSES: This study is to evaluate a ground water level effect on frost heaving in road pavements. METHODS: The effects of water table on frost heaving in pavement systems were evaluated from the mechanical analysis using FROST program. The input parameters and boundary conditions were determined by considering climates, pavement sections, and material properties specially subgrade soil types in Korea. RESULTS: When the water table located above the freezing depth, amount of frost heaving caused by freezing the water in pavement itself was big enough to damage in pavement system, although pavement system consists of fully non-frost-susceptible materials with sufficient thickness of anti-freezing layer. The amount of frost heaving was decreased rapidly with increasing the distance between the water table and freezing depth. CONCLUSIONS: It was concluded that there is no engineering problems related with frost heaving in practical sense when the distance between freezing depth and water table is over 1.5m for having subgrade soils less than 50% of #200 sieve passing to meet specification on quality control in Korea.

A Study on the Unsteady Fluid Forces Acting on a Heaving Foil (히빙운동익에 작용하는 비정상 유체력 특성)

  • Yang Chang-Jo
    • Journal of Advanced Marine Engineering and Technology
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    • v.30 no.1
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    • pp.150-156
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    • 2006
  • A Flapping foil Produces an effective angle of attack, resulting in a normal force vector with thrust and lift components, and it can be expected to be a new highly effective propulsion system. A heaving foil model was made and it was operated within a circulating water channel at low Reynolds numbers. The unsteady thrust and lift acting on the heaving foil were measured simultaneously using a 6-axis force sensor based on force and moment detectors. We have been examined various conditions such as heaving frequency and amplitude in NACA 0010 Profile. The results showed that thrust coefficient and efficiency increased with reduced frequency and amplitude. We also Presented the experimental results on the unsteady fluid forces of a heaving foil at various Parameters.

Experimental Study about Reduction of Frost-heaving in Railway roadbed which using wasted tire chips (폐타이어 칩을 활용한 철도노반 동상저감에 대한 실험적 고찰)

  • Lee, Syeung-Youl;Kim, Young-Chul;Kim, Nam-Hong;Kim, Myoung-Soo
    • Proceedings of the KSR Conference
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    • 2010.06a
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    • pp.633-639
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    • 2010
  • Cold area in korea, railway roadbed and gravel ballast was occurred frost-heaving. So during winter, track was rising and during thaw, track was sinking. In order to prevent the damage of frost-heaving, we have applied a few countermeasures which are circumfusion of calcium chloride and replacement of gravel ballast method. This countermeasures effect is feeble, not continuous and not eco-friendly. This study suggested that we use wasted tire-chips in frost-heaving area and considered appropriate new method to maintenance. This method was named "A Method of Wasted Tire-Chips Post". To prove effect of this method, we have tested in laboratory and field. The result of frost-heaving-ratio field test was decreased frost-heaving-ratio about 50% using "A Method of Wasted Tire-Chips Post".

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Study on Unsteady Forces Acting on a Heaving Foil (히빙운동익에 작용하는 비정상 유체력 특성)

  • Yang, Chang-Jo;Kim, Beom-Seok;Choi, Min-Seon;Lee, Young-Ho
    • Proceedings of the Korean Society of Marine Engineers Conference
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    • 2005.06a
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    • pp.222-227
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    • 2005
  • A Flapping foil produces an effective angle of attack, resulting in a normal force vector with thrust and lift components, and it can be expected to be a new highly effective propulsion system. A heaving foil model was made and it was operated within a circulating water channel at low Reynolds numbers. The unsteady thrust and lift acting on the heaving foil were measured simultaneously using a 6-axis force sensor based on force and moment detectors. We have been examined various conditions such as heaving frequency and amplitude in NACA 0010 profile. The results showed that thrust coefficient and efficiency increased with reduced frequency and amplitude. We also presented the experimental results on the unsteady fluid forces of a heaving foil at various parameters.

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Frost Heaving Pressure and Physical Characteristics of the Railway Roadbed Materials (철도노반재료의 동상팽창압 및 물리적 특성 평가)

  • Shin Eun-Chul;Park Jeong-Jun;Kim Jong-In
    • Journal of the Korean Society for Railway
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    • v.8 no.1
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    • pp.57-62
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    • 2005
  • The frost heaving pressure can be a problem for weakening of the railway roadbed material. This study was initiated to investigate the soils frost heaving pressure and physical characteristics(Liquid limit, permeability, SEM analysis) resulting from freezing and freezing-thawing cycle process. Therefore, upon freezing a saturated soil in a closed-system from the top, a considerable pressure was developed. Weathered granite soils, sandy soil were used in the laboratory freezing test which sometimes subjected to thermal gradients under closed-systems. The frost heaving pressure arising within the soil samples and the temperature of the samples inside were monitored with elapsed time. The degree of saturation versus heaving pressure curve is also presented for weathered granite soil and the maximum pressure is closely related to this curve. Based on the laboratory test results, fine-grained soils with strong attractive forces between soil grains md water molecules, and additional water is attracted into the pores leading to further volume changes and ice segregation.

A Study on Heaving Phenomenon by Model Test (실내모형실험을 통한 히빙 이론에 관한 연구)

  • Oak, Yong-Kwan;Im, Jong-Chul;Kwon, Jeong-Keun
    • Proceedings of the Korean Geotechical Society Conference
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    • 2008.10a
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    • pp.1144-1156
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    • 2008
  • In this paper, heaving phenomenon is analyzed by laboratory tests. A laboratory test is consist of building soft clay foundation in plane-strain soil tank, construction of retaining wall, and excavation work. And range of shear strain, and destruction shape about soft clay foundation is compared, and analyzed with results of proposal formula. Using this study, safety factor is suggested for heaving phenomenon in the construction of wall on the soft clay. Actual theory is suggested by this suggested safety factor. There are various proposal formula for heaving phenomenon. For example, Terzaghi & Peck, Tschebotarioff, Bjerrum & Eide(Experience formula) and so on. Terzaghi & Peck's proposal formula is chosen, compared with laboratory test's result and analyzed in this study. A soft clay used in study is assumed homogeneous. A Depth of foundation is enough to observe shear strain by heaving phenomenon. Retaining wall is enough hard not to have vertical displacement.

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The Relationship between Loading Velocity and Ground Heaving Characteristics (재하속도와 지반융기 특성의 상호관계)

  • Oh, Se-Wook
    • Journal of the Korean GEO-environmental Society
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    • v.7 no.3
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    • pp.77-83
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    • 2006
  • The purpose of this study is to analyze lateral displacement behavior of clay layers in case of the banking in soft ground through model tests. Seven model tests varying with thickness of soft clay and loading velocity are performed to correlate between ground heaving and loading velocity. In case of low loading velocity, vertical settlement below loading plate and small ground heaving are obviously observed. In case of the high loading velocity, it is shown that both soil displacement at the end of a loading plate and surface heaving are large. In addition, the calculated displacements show good agreement with three cases of field measurements in clay with high moisture contents so that we can predict the range of heaving area and the amount of heaving.

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A Model Tests on the Shape of Deformation caused by Sea dike Construction (방조제 축조에 따른 치환 및 융기의 형태에 관한 모형실험)

  • 장병욱;김성필;우철웅
    • Proceedings of the Korean Society of Agricultural Engineers Conference
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    • 1998.10a
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    • pp.419-424
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    • 1998
  • The deduction methods for forced displacement depths caused by sea dike construction often assumed the shape of forced displacements and heaving. To investigate the shape of forced displacements and heaving, a model tests was performed. Results of the tests are as follows; 1) The shape of forced displacements can be assumed ellipse. 2) The shape of heaving can not be assumed uniform shape like a circle and Extents of heaving was varied with the loading height and width. 3) The shape of forced displacements caused by step construction, pebble embankments and soil embankments, also investigated.

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