• Title/Summary/Keyword: Frost-susceptibility soil

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Investigation of the ASTM International frost heave testing method using a temperature-controllable cell

  • Hyunwoo, Jin;Jangguen, Lee;Byung-Hyun, Ryu
    • Geomechanics and Engineering
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    • v.31 no.6
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    • pp. 583-597
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    • 2022
  • Frost heave can cause uneven ground uplift that may damage geo-infrastructure. To assist damage-prevention strategies, standard frost heave testing methods and frost susceptibility criteria have been established and used in various countries. ASTM International standard testing method is potentially the most useful standard, as abundant experimental data have been acquired through its use. ASTM International provides detailed recommendations, but the method is expensive and laborious because of the complex testing procedure requiring a freezing chamber. A simple frost heave testing method using a temperature-controllable cell has been proposed to overcome these difficulties, but it has not yet been established whether a temperature-controllable cell can adequately replace the ASTM International recommended apparatus. This paper reviews the applicability of the ASTM International testing method using the temperature-controllable cell. Freezing tests are compared using various soil mixtures with and without delivering blow to depress the freezing point (as recommended by ASTM International), and it is established that delivering blow does not affect heave rate, which is the key parameter in successful characterization of frost susceptibility. As the freezing temperature decreases, the duration of supercooling of pore water shortens or is eliminated; i.e., thermal shock with a sufficiently low freezing temperature can minimize or possibly eliminate supercooling.

Development of experimental apparatus to evaluate frost heave and pressure (토사의 동상량 및 동상력 측정을 위한 실내 실험장치 개발)

  • Ko, Sung-Gyu;Choi, Chang-Ho;Chae, Jong-Gil
    • Proceedings of the Korean Geotechical Society Conference
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    • 2010.09b
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    • pp.131-137
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    • 2010
  • `Frost heave' is volumetric extension behavior of soil due to freezing. It could have a bad effect to foundations of infrastructures like building, road, railroad and bridge. Therefore, it is considered as a primary design parameter with 'adfreeze bond' and 'creep deformation' for foundation design in cold region. In some countries, studies for analyzing frost heave in many ways have being performed, however, only a few studies for evaluating frost susceptibility of soils by measuring frost heave rate of frozen soils in Korea. For analyzing frost heave as a foundation design parameter, both frost heaving rate and heaving pressure are should be addressed in study. Hence, in this study, development of experimental apparatus to evaluate frost heave and pressure is suggested.

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The Frost Heaving Susceptibility Evaluation of Subgrade Soils Using Laboratory Freezing System (실내 동상시스템을 이용한 노상토의 동상민감성 평가)

  • Shin, Eun Chul;Ryu, Byung Hyun;Park, Jeong Jun
    • Journal of the Korean Geosynthetics Society
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    • v.12 no.2
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    • pp.13-23
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    • 2013
  • The Korean Peninsula is considered as a seasonal frozen area that is thawed in the spring and frozen in the winter. The influence of fines of the frost susceptibility of subgrade soils were established by laboratory freezing tests simulating closely the thermal conditions in the field. During the winter season, the climate is heavily influenced by the cold and dry continental high pressure. Because of siberian air mass, the temperature of January is $-6{\sim}-7^{\circ}C$ on average. This chilly weather generate the frost heaving by freezing the moisture of soil and damage potential of the geotechnical structure. In the freezing soil, the ice lenses increase the freeze portion of soil by absorbing the ground water with capillary action. However, the capillary characteristics differ from the sort of soil on the state of freezing condition. In this study, ten soil samples are prepared. The basic physical property tests were performed by following the Korean Industrial Standard and the soil specimens were classified by the Unified Soil Classification System (USCS). These classified soils are used to perform the laboratory opened systems freezing test in order to determine the frost heaving characteristics of soils such as unfrozen water content, heaving amount, and freezing depth.

Field Experiments for Reducing Frost Susceptibility Using Recycled Tire Powder (폐타이어 파우더 혼합이 동상억제에 미치는 영향에 관한 야외실험 연구)

  • Kim, Hak-Sam;Suzuki, Teruyuki;Fukuda, Masani;Seo, Sang-Youl;Yamashita, Satoshi
    • Journal of the Korean Geotechnical Society
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    • v.26 no.4
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    • pp.5-14
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    • 2010
  • Three years of frost heave field experiments were conducted to evaluate a method for reducing heave using a recycled tire powder-soil mixture. By mixing Tomakomai soil with 20% recycled tire powder, frost heave amount was drastically decreased. The results of the field experiment confirm that recycled tire powder is an excellent material for use in controlling the total amount of heave. The restraining effect of a recycled tire powder-soil mixture is qualitatively analyzed based on amount of frost heave, frost heave ratio, thermal conductivity, permeability and segregation potential theory.

Experimental Assessment and Specimen Height Effect in Frost Heave Testing Apparatus (동상시험장비의 실험적 검증 및 시료크기의 영향에 관한 연구)

  • Jin, Hyunwoo;Ryu, Byunghyun;Lee, Jangguen
    • Journal of the Korean GEO-environmental Society
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    • v.20 no.1
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    • pp.67-74
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    • 2019
  • Frost heave is one of the representative engineering characteristics in cold regions. In South Korea, which is located in seasonal frost area, structural damage caused by frost heave and thaw happens and the need for research on the frost heave is increasing. In this paper, newly developed transparent temperature-controllable cell is used to focus on the frost heave. Frost susceptible artificial soil is used to analyze water intake rate which is one of the important factors in frost susceptibility criteria. Frost heave rate and water intake rate have similar behavior after heave by freezing of pore water converges. O-ring installed in the upper pedestal to measure water intake rate generates side friction between the inner wall of the freezing cell and O-ring, thereby hindering frost heave. Therefore, the frost susceptibility criteria using the water intake rate is not reliable. It is appropriate to use frost heave rate which has similar behavior with water intake rate. Frost heave tests were performed under two different specimen heights. Overburden pressure, temperature gradient and dry unit weight were set under similar state. Based on laboratory testing results, frost heave is independent on the specimen height.

Assessment of the Correlation between Segregation Potential and Hydraulic Conductivity with Fines Fraction (세립분 함유량에 따른 동상민감성 지수와 수리전도도의 상관관계 평가)

  • Jin, Hyunwoo;Kim, Incheol;Eun, Jongwan;Ryu, Byung Hyun;Lee, Jangguen
    • Journal of the Korean Geotechnical Society
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    • v.37 no.12
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    • pp.47-56
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    • 2021
  • The cryosuction (negative pore pressure) in freezing soils causes groundwater migration from the frozen fringe to freezing front for ice lens formation. Frost heave and heaving pressure by ice lens cause damage to ground infrastructure. In order to prevent damage by the frost heave, various frost susceptibility criteria have been proposed. The SP (Segregation Potential) is the most widely used classification criterion for frost susceptibility in cold regions. The expansion of the ice lens by the migration of the groundwater is a key role in frost heave mechanism, and thus it is necessary to evaluate the hydraulic conductivity. In this paper, soil mixtures of coarse-fines (sand-silt) were prepared in various weight fractions and used for frost heave and column permeability test. For each case, the SP and the hydraulic conductivity were derived and correlations were analyzed. As a results, the transition threshold of the SP and the hydraulic conductivity were shown at 20% and 50% of the silt weight fraction, respectively. Although there are difference between these transition thresholds, these two coefficients show a specific correlation. In the future, additional study should be conducted for detailed analysis of the threshold transition values between SP and hydraulic conductivity.

Freezing and Bearing Capacity Characteristics of Road Foundations under Temperature Condition (온도조건에 의한 도로하부 지반의 동결 및 지지력 특성)

  • Shin, Eun-Chul;Kim, Sung-Hwan;Park, Jeong-Jun
    • Journal of the Korean Geotechnical Society
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    • v.28 no.3
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    • pp.5-14
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    • 2012
  • In the current design codes for anti-freezing layer, the thickness of anti-freezing layer is calculated by freezing depth against the temperature condition. Therefore, they have a tendency of over-design and uniform thickness without the considerations of thermal stability, bearing capacity and frost susceptibility of materials. So, it is essential for studying the appropriateness and bearing capacity of road foundation materials as well as their seasonal and mechanical properties to take an appropriate and reasonable design of the road structure system. In this paper, the freezing and bearing capacity characteristics of typical road foundation materials were evaluated in the large scale laboratory test. LFWD (light falling weight deflectometer) was used to determine the change of elastic modulus ($E_{LFWD}$) caused by to the frost heave and thaw. Furthermore, the influence of crushed natural aggregate on the freezing of the subgrade soil was studied to verify the function and effectiveness of the anti-freezing layer.

Earth Hummocks on the Crater Floor of Baegnokdam at Mt. Halla (한라산 백록담 화구저의 유상구조토)

  • 김태호
    • Journal of the Korean Geographical Society
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    • v.36 no.3
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    • pp.233-246
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    • 2001
  • Topography and soil characteristics of earth hummocks are examined in the summit crater of Mt. Halla in order to evaluate their morphoclimatic significance as an indicator of a periglacial environment. The hummocks are generally oval in outline, and they have a diameter of 42 to 200 cm and a height of 9 to 27 cm Seventeen hummocks are distributed In a 5$\times$5 m quadrat at an interval of 20 to 40 cm Excavation reveals the cryoturbated soil profiles which consist of upper dark brown layer and lower brown layer. The dark brown layer has 61.8% total clay and silt content, implying Its high frost susceptibility Earth hummocks have the dry density of 0.761 to 1.009 g/㎤ the void ratio of 1420 to 2.008, and the moisture content of 24.2 to 68.8% by weight, respectively. The hummocky soils become compacted and desiccated downward. Earth hummocks are frozen as a hard solid mass during winter and early spring, and freezing fronts reach about 45 cm below their apices. The layer with high lute content appears in the upper horizon of dark brown soil. but Ice lenses are not so much segregated The moisture content of hummocky soils generally increases up to 73.9 to 118.80% for dark brown layer and 49.9 to 82.8% for brown layer during thins period Because the cohesive soil of earth hummocks indicates 72.8% of the moisture content as a liquid limit, the dark brown layer is highly fluid and consequently subject to cryoturbation processes.

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