• KSCE Journal of Civil and Environmental Engineering Research
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• v.8 no.2
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• pp.147-154
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• 1988

Korea has the ground which freezes in winter and melts in warmer seasons by turns. Therefore, in designing civil-structures or buildings on such ground, the depth of seasonal frost penetratio must be considered. In this paper, approximate contours of the maximum depth of frost penetration in Korea is presented. It was found that the maximum depth of frost penetration did not have the linear relationship to square root of the freezing index. In order to establish more reliable method to estimate the maximum depth of frost penetration, a new empirical equation is introduced. In the presented equation, the dry unit weight and water content of soil are considered in addition to the freezing index. And the equation is compared with other previous equations used so far.

• Geotechnical Engineering
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• v.14 no.1
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• pp.49-58
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• 1998

It was investigated whether the scrap tire can be recycled as a construction material for controlling the frost heave of the ground. Some frost heave tests and a frost penetration depth test in the laboratory were performed on the weathered granite soil mitred with variable amount of scrap tire powder under the atmospheric temperature at -$17^{\circ}$ to find the basic effects of the scrap tire on the control of frost. The frost heave control layer of the crushed stone mixed with scrap tire chips directly below thin subbass in the bituminous pavement was found to be effective for practical use. And the equation for the required thickness of this frost heave control layer with freezing index was suggested.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.475-482
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• 2005

Many public facilities including roadway, railway, and embedded pipe lines in this country have been damaged by the repeated freezing and thawing of the soil during winter and spring every year. However, there are only few research results in field of frozen ground in this country. Also, there are no the formulation of the reasonable equation for frost penetration depths and of the criterion for identifing potentially frost-susceptible soil in design manual of pavement yet. Through this study it is anticipated to asses the frost action problem in roadway, railway, and water suppply lines and to establish the design criterion about pavement in seasonal cold region.

• Review of Korea Contents Association
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• v.12 no.4
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• pp.47-50
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• 2014

• Magazine of the Korean Society of Agricultural Engineers
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• v.32 no.3
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• pp.39-46
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• 1990

This paper was analized the thermal conductivity of polystylene (TENSAR- GEOGRID) embeding into the subbase through frost penetration depth, frost heave, change of bearing capacity, and soil moisture movement due to freezing, thawing and icing actions, and their results were as follows : 1.The change of temperature into the sub-base was much increased by the Tensar-Geogrid insertion, and the frost penetration and frost heave were decreased as the thinner of the insulation thickness but the thawing velocity of melting period was appeared to be faster in case of non-insulated. 2.The frost heave had a close relationship with the thickness of insulations which was reasonably included anti-frost effects. 3.The moisture content during the freezing period of upper layer of the insulation insertion was increased by 15 per cent but it was returned to initial state of the thawing period, and at the down layer temporarily increased by 10 per cent and returned to the original state at once. 4.The insulation was acted as a function of distribution of surcharge, and the settlement of the sub-base was about 1.5 mm under 15 tonnage of load and which was included within the allowable limits. 5.The sliding resistance due to the icing which was induced by the insulation insertion into the sub-base was appeared as more 40 per cent than noninsulation area, so that the insulations should be restricted on the place such as mountains, curved and cross area which were required the braking power under the traffics.

• Journal of the Korean GEO-environmental Society
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• v.17 no.1
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• pp.49-54
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• 2016

An active layer distributed on surface of an extreme cold region causes a frost heave by repeating the freezing and thawing according to the seasonal temperature change. Since the height of frost heave is greatly affected by the thickness of active layer, an accurate evaluation of the thickness of active layer is necessary for the safe design and construction of the infrastructure in the extreme cold region. In this study, dynamic cone penetrometer, which is miniaturized in-situ penetration device, is applied for the evaluation of active layer depth distribution. As the application tests, two dynamic cone penetration tests were conducted on the study sites located in Solomon and Alaska. In addition, ground temperature variations were obtained. As the results of the application tests, the depth of interface between the active layer and the permafrost was evaluated from the difference in dynamic cone penetration indexes of the active layer and the permafrost, and a layer was detected around the interface considered as an ice lens layer. Also, the interface depths between the above zero and the below zero temperature determined from the ground temperature variations correspond with the interface depths evaluated from the dynamic cone penetration tests. This study demonstrates that the dynamic cone penetrometer may be a useful tool for the evaluation of the active layer in the extreme cold region.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.3D
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• pp.433-439
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• 2011

The frost depth(frost penetration) is used to install anti-frost heave layers in pavement designs. The freezing index is calculated by an annual accumulated value of multiplying the period of time with temperatures below zero, and the corresponding temperature. Therefore, the DAAT(daily average air temperature) calculation method may play an effect on the FI(freezing index). The Weather Observatory used to supply 4 average air temperatures per day, but currently supplies 8 per day. With this study, we divided the southern part(below FI=$350^{\circ}C{\cdot}day$) of the Korean peninsula into 6 areas according to site conditions(low embankment, embankment-cutting slope, and the cutting slope) and established a field measurement system for 15 positions to check the effects on the result of FI according to differing DAAT calculation methods. The air temperatures obtained by the field measurement system was used to calculate and compare the FI. As a result, the freezing index calculated based on the $DAAT_4(T_4)$ is normally greater by 3% than the one on $DAAT_8(T_8)$. In addition, the calibration equation for the freezing index using air temperatures was proposed through the research.

• Journal of Korean Society of Transportation
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• v.15 no.3
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• pp.7-23
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• 1997

우리나라의 전면적인 약 95%가 계절적 동결지역에 속하며 동상과 융해로 인해 도로등 지반구조물은 피해을 입는다. 본 논문에서는 국립건설시험소의 10년간 실측자료중 지역별로 대표하여 15개 도시 528개 지점을 선정하여 최대동결지수를 4개 그룹(250이하, 250∼400, 400∼600, 600이상)으로 분류하여 분석하였다. 또한 동결심도 계산에 동결지수외에 흙의 함수비와 전조밀도를 각각 추가로 고려하여 새로운 산정식을 제시하였다. 그리고 지역에 따른 과다산정을 막기 위하여 동결지수 분류별로 4그룹으로 세분화하여 경제적인 설계가 가능하도록 하였다. 새 제안식과 기존식을 비교하여 보았을 때 새 제안식이 기존식보다 전반적으로 크게 산정되나 그 지역의 함수비나 건조밀도를 추가로 고려하였으므로 보다 합리적인 산정식이라 할 수 있다.

• 한국방재학회:학술대회논문집
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• 2011.02a
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• pp.82-82
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• 2011

현재 도로 포장 설계시 동결심도의 결정은 30년간 관측한 기상자료 분석을 통해서 얻은 동결지수를 근거로 하여 동결심도를 산정한다. 그러나 기후 온난화 현상 등 변화된 기상조건과 대기온도를 근거로 작성된 동결지수와 대기온도에 따른 실제 포장 내부의 온도 변화를 반영하지 못하고 있다. 따라서, 본 연구에서는 설계시 산정된 동결심도와 실제 현장의 동결심도의 차이를 확인하기 위하여 한반도 북부지역을 동결지수에 따라 동결지수 $550{\sim}650^{\circ}C{\cdot}$일, $450{\sim}550^{\circ}C{\cdot}$일, $350{\sim}450^{\circ}C{\cdot}$일, $350^{\circ}C{\cdot}$일 이하로 구분하여 15개 지역을 선정하였고, 각 지역별로 절토부, 절성경계부, 저성토부(2m 이하 성토부) 구간으로 45단면을 구분하여 현장계측시스템을 구축하였다. 그리고 현장계측시스템으로부터 얻어진 대기온도와 포장층별 온도를 이용하여 현장 동결심도를 산정하고 동결심도 산정식의 동결심도와 비교하였다. 또한, 현장 동결심도를 이용하여 동결심도선도를 작성하였다.

• Journal of the Korean Geotechnical Society
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• v.16 no.1
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• pp.179-189
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• 2000

The purpose of this research is to complement the existing researches on landfill bottom liners behavior during the periods of freeze and thaw. Landfill-related researches have been typically focused on small-scale soil samples that are often compacted under conditions different from those used in the field. Although these tests have been invaluable in clarifying the problem of freeze and thaw, extending the results of such experimental studies to prototype landfills are questionable. In this investigation, the author utilized a large scale laboratory simulation allowing inclusion of the field depth of the cover systems, layered soil profiles, rainfall simulation, a cold climate and boundary conditions similar to those encountered in the landfill. The soil materials were stabilized soils (mixed clays, cements, and minerals) instead of clays. The bottom liners are made up of drainage layer (30 cm), stabilized layer (75 cm), and leach collection layer (60 cm). The stabilized layers are made up of supporting layer (45 cm) and low permeable layer (30 cm) - consisting of $P_A\; and\; P_B$ layer. As a results, depths of penetration increased by about 2~5 more centimeters at rainfall simulated designs than those at no rainfall simulated designs (that is design 3, design 5 and design 7) - it increased by about 20mm/day in the bottom liners and frost heaves also increased it by a few millimeters. Also, a few cracks appeared partly. According to these results, we can surmise that the compacted stabilized soil is more reliable than the compacted clay liners for construction of the landfill liners.