• Title/Summary/Keyword: Frost heave ratio

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Evaluation of Frost Heave Prediction and Frost Susceptibility in Sample using JGS Test Method (일본 동상성판정기준을 적용한 시료의 동상예측 및 동상성 평가)

  • Kim, Young-Chin;Hong, Seung-Seo
    • Proceedings of the Korean Geotechical Society Conference
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    • 2008.03a
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    • pp.926-931
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    • 2008
  • This paper show two different standardized test methods(Japanese Geotechnical Society; JGS 2003). One test is a "Test Method for Frost Heave Prediction Test, JGS 0171-2003", and the other test is a "Test Method for Frost Susceptibility, JGS 0172-2003". The purpose of this test is to obtain the freezing rate(freezing speed), frost heave ratio(heave to sample height), frost heave rate(heaving speed), and other parameters to be used for frost heave prediction and determine the frost susceptibility by freezing test with water intake. This method shall be used to predict the frost heave in frozen ground and evaluate the frost susceptibility of natural and replacement materials.

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Experimental assessment of the effect of frozen fringe thickness on frost heave

  • Jin, Hyun Woo;Lee, Jangguen;Ryu, Byun Hyun;Shin, Yunsup;Jang, Young-Eun
    • Geomechanics and Engineering
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    • v.19 no.2
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    • pp.193-199
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    • 2019
  • A frozen fringe plays a key role in frost heave development in soils. Previous studies have focused on the physical and mechanical properties of the frozen fringe, such as overall hydraulic conductivity, water content and pore pressure. It has been proposed that the thickness of the frozen fringe controls frost heave behavior, but this effect has not been thoroughly evaluated. This study used a temperature-controllable cell to investigate the impact of frozen fringe thickness on the characteristics of frost heave. A series of laboratory tests was performed with various temperature boundary conditions and specimen heights, revealing that: (1) the amount and rate of development of frost heave are dependent on the frozen fringe thickness; (2) the thicker the frozen fringe, the thinner the resulting ice lens; and (3) care must be taken when using the frost heave ratio to characterize frost heave and evaluate frost susceptibility because the frost heave ratio is not a normalized factor but a specimen height-dependent factor.

An experimental study for reducing frost susceptibility using granulated used-tire (폐타이어분말 혼합이 동상억제에 미치는 영향에 관한 실험적 연구)

  • Kim, Hak-Sam
    • Journal of the Korean Society of Industry Convergence
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    • v.9 no.2
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    • pp.147-154
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    • 2006
  • The authors conducted field experiments of frost heave to evaluate a method for reducing frost susceptibility using granulated used-tire mixture for 3 winters. Qualitative analyses for the evaluation of restraint effect of frost susceptibility by utilizing granulated used-tire soil mixture were conducted with the segregation potential concept and frost heave ratio. By mixing soil with granulated tire, the frost susceptibility was decreased drastically. From the result of the analyses, it was confirmed that granulated tire is an excellent material in controlling the frost susceptibility.

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Frost Heave of Frost Susceptible Soil According to Performance of Thermo-syphon (열 사이펀 성능에 따른 동상민감성 지반의 거동 비교)

  • Park, Dong-Su;Shin, Mun-Beom;Seo, Young-Kyo
    • Journal of the Korean Geotechnical Society
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    • v.37 no.10
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    • pp.27-40
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    • 2021
  • The construction method to prevent the frost heave or thaw settlement is called the ground stabilization method, and the thermo-syphon is one of the typical ground stabilization methods. The thermo-syphon has recently been developed with a simple analysis model and thermal analysis has been carried out, but the frost heave of frost susceptible soil was not considered. This study was conducted using ABAQUS internal user subroutine to develop the numerical analysis model (Coupled thermo-mechanical) that can simultaneously perform thermal analysis for the temperature change of the soil according to the thermo-syphon and structural analysis to predict the frost heave of the soil accordingly. As a result of the numerical analysis, the frost heave of the soil decreased as the performance of the thermo-syphon increased. As for the main results, when the thermo-syphon which has contain 25%, 50%, and 100% of refrigerant filling ratio was applied, the reduction ratio of the frost heave was 5.5%, 14.4%, and 21% respectively.

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.

Optimization of hydraulic section of irrigation canals in cold regions based on a practical model for frost heave

  • Wang, Songhe;Wang, Qinze;An, Peng;Yang, Yugui;Qi, Jilin;Liu, Fengyin
    • Geomechanics and Engineering
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    • v.17 no.2
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    • pp.133-143
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    • 2019
  • An optimal hydraulic section is critical for irrigated water conservancy in seasonal frozen ground due to a large proportion of water leakage, as investigated by in-situ surveys. This is highly correlated with the frost heave of underlain soils in cold season. This paper firstly derived a practical model for frost heave of clayey soils, with temperature dependent thermal indexes incorporating phase change effect. A model test carried out on clay was used to verify the rationality of the model. A novel approach for optimizing the cross-section of irrigation canals in cold regions was suggested with live updated geometry characterized by three unique geometric constraints including slope of canal, ratio of practical flow section to the optimal and lining thickness. Allowable frost heave deformation and tensile stress in canal lining are utilized as standard in computation iterating with geometry updating while the construction cost per unit length is regarded as the eventual target in optimization. A typical section along the Jinghui irrigation canal was selected to be optimized with the above requirements satisfied. Results prove that the optimized hydraulic section exhibits smaller frost heave deformation, lower tensile stress and lower construction cost.

A Study on the Engineering Characteristics of the plaster-soil uiiitures (석고플라스터 혼합토의 공학적 특성)

  • 도덕현;정성모
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.27 no.4
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    • pp.53-60
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    • 1985
  • The plaster mixed to loam and sandy soil from 4 to 12 percent by dry soil weight, and the compaction, permeability, CBR, unconfined compressive strength and freezingthawing test were performed The results obtained are summarized as follows; 1.The coefficient of permeability reduced sharply at the plaster content of 4 percent, and in the CBR test, the swelling ratio reduced by the increment of plaster content. 2.The addition of plaster increased the unconfined compressive strength by the cementing effect, and it was found that the optimum plaster content, existed with the soil type, which showed the maximum strength 3.It was possible to enhance the unconfined compressive strength of the gypsum-lime-soil mixtures when the optimum content of plaster was mixed to the hydrated lime. 4.In case of sandy soil, the relative frost heave decreased with the mixture of plaster, however in loam soil, the relative frost heave began to increase at the plaster content of 12 percent than non-treated soil. Therefore the optimum plaster content existed for protecting frost heave by the different soil type. 5.The above summarized results make it possible to expect the effects such as improvement of soil properties, decrement of permeability, increment of unconfined compressive strength, and protection of frost heave, etc, therefore, it is considered that it is possible to it is plaster as sub-base materials of road.

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Influencing Factors on Freezing Characteristics of Frost Susceptible Soil Based on Sensitivity Analysis (민감도 분석을 기반으로 한 시료의 동결 특성에 미치는 영향인자 분석)

  • Go, Gyu-Hyun;Lee, Jangguen;Kim, Minseop
    • Journal of the Korean Geotechnical Society
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    • v.36 no.8
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    • pp.49-60
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    • 2020
  • A fully coupled thermo-hydro-mechanical model is established to evaluate frost heave behaviour of saturated frost-susceptible soils. The method is based on mass conservation, energy conservation, and force equilibrium equations, which are fully coupled with each other. These equations consider various physical phenomena during one-dimensional soil freezing such as latent heat of phase change, thermal conductivity changes, pore water migration, and the accompanying mechanical deformation. Using the thermo-hydro-mechanical model, a sensitivity analysis study is conducted to examine the effects of the geotechnical parameters and external conditions on the amount of frost heave and frost heaving rate. According to the results of the sensitivity analysis, initial void ratio significantly affects each objective as an individual parameter, whereas soil particle thermal conductivity and temperature gradient affect frost heave behaviour to a greater degree when applied simultaneously. The factors considered in this study are the main factors affecting the frost heaving amount and rate, which may be used to determine the frostbite sensitivity of a new sample.

Frost-Heaving Characteristics of Soil Mixed with Discarded Tire Powder (폐타이어 파우더 혼합토의 동상 특성)

  • Kim, Hak-Sam;Seo, Sang-Youl;Nakamura, Dai;Fukuda, Masami;Yamashita, Satoshi;Suzuki, Teruyuki
    • Journal of the Korean Geotechnical Society
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    • v.26 no.4
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    • pp.15-26
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    • 2010
  • To determine the frost heave suppressing mechanism of soil mixed with tire powder, we conducted three kinds of laboratory experiments: measurement of unfrozen water, evaluation of thermal conductivity, and a frost heave. In this research, we focused on changes in the coefficient of permeability of the mixed soil, and first found that of the unsaturated soil. Next, in the case of the presence of ice, we took the ice-impeding factor into consideration to derive the coefficient of permeability of the frozen fringe from the area ratio of the soil and tire powder in mixed soil. The results show a positive correlation between the water intake rate and the coefficient of permeability. Moreover, we found that the frost heave decreased thanks to a reduction in the permeability and a fall in the unfrozen water content of the soil mixed with tire powder. We also calculated the weight of the water content of the soil and tire powder void quantitatively using the result of the volumetric ratio of mixed soil.

Freezing and Deflection Characteristics of Flexible Pavement Structure Using Frost Model Test (동상모형실험을 통한 아스팔트 포장체의 동결 및 처짐 특성)

  • Shin, Eun-Chul;Hwang, Soon-Gab;Park, Jeong-Jun
    • Journal of the Korean Geosynthetics Society
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    • v.11 no.3
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    • pp.27-35
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    • 2012
  • In this paper, the frost heaving and thawing characteristics of flexible pavement structure were evaluated in the large scale freezer which have a specification of temperature range $-20^{\circ}C{\sim}10^{\circ}C$ and $3.2m(L){\times}3.2m(B){\times}2.4m(H)$ in size. The insulated steel box with the size of $0.9m(L){\times}0.9m(B){\times}0.9m(H)$ was used to simulate actual pavement road structure. The variation of temperature, frost heave amount and frost heave pressure were measured through the instrument of TDS-602 data logger. LFWD (light falling weight deflectometer) was used to determine the change of deflection due to the frost heaving and thawing. Furthermore, the influence of aggregate layer to the freezing of the subgrade soil was studied to verify the function and effectiveness of the anti-freezing layer.