• International Journal of Highway Engineering
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• v.6 no.3 s.21
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• pp.55-64
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• 2004

Maximum dry unit weight, ${\gamma}_{dmax}$, is the most important engineering properties for subgrade soil. Existing models to predict ${\gamma}_{dmax}$ containing many parameters, seem to be rather complex. This paper presents new simple models to predict ${\gamma}_{dmax}$. for sandy soils, A number of sieve analysis and compaction tests for 36 types of sands were conducted to develop the regression-based models. Parameters used to estimate ${\gamma}_{dmax}$ are both the geometric mean and geometric standard deviation of the soils, or the particle-size distribution curve parameters. Maximum dry unit weights predicted by the models are in good agreement with the laboratory measurements for the soil samples obtained at 16 locations within the Korea.

• Proceedings of the Korean Society of Disaster Information Conference
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• 2023.11a
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• pp.251-252
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• 2023

본 연구에서는 오염물의 선택적 흡수가 가능한 반응재료의 분광정보 예측을 위하여 반응재료 배합 조건에 따른 분광정보와 최대건조단위중량의 상관관계를 평가하였다. 그 결과, 배합 조건에 따라 최대건조단위중량 증가하게 되면, 최대분광반사율은 감소하였고, 이를 바탕으로 분광정보 경향의 예측이 가능하였다.

• Proceedings of the Korean Society of Disaster Information Conference
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• 2023.11a
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• pp.337-338
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• 2023

본 논문에서는 유류 오염물의 흡수 반응이 가능한 반응재료에 대하여 지중 구조 재료로서의 적용성 검토를 목적으로 배합조건에 따른 다짐시험을 실시하였다. 다짐시험 결과, 주요 반응물질이 최적함수비에 미치는 영향은 미미하였으나, 최대건조단위중량의 영향인자로 평가되었다.

• Journal of the Society of Disaster Information
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• v.19 no.4
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• pp.950-957
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• 2023

Purpose: The response technology is needed to prevent the spill of highly toxic oil contaminants in advance. Therefore, this paper described the results of an experimental study to predict the engineering properties of the developed reactive material. Method: Compaction tests and spectral information acquisition experiments were conducted on the reactive materials, and the results were evaluated. In addition, the correlation between spectral information and maximum dry unit weight was analyzed to evaluate the possibility of predicting the engineering properties for reactive materials. Result: The compaction test results showed that the maximum dry unit weight was in the range of approximately 9kN/m³ to 10kN/m³. The spectral information confirmed that the maximum reflectance decreased as the polynorbornene decreased. Conclusion: It was confirmed that the maximum dry unit weight of the reactive material for absorbing oil contaminants can be predicted using the maximum reflectance according to the component ratio of the reactive material.

• Proceedings of the Korean Geotechical Society Conference
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• 1998.03a
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• pp.315-320
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• 1998

• Journal of the Korean GEO-environmental Society
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• v.18 no.1
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• pp.23-29
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• 2017

This study, to provide quantitative data related to compaction characteristics, identifies the compaction characteristics of various types of soil samplers, in relation to their particle-size distribution and plasticity degree, and the compaction characteristics of artificially created granular materials, in relation to their A & D compaction. The results of the experiments show as follows. $r_{dmax}$ of clay is less than those of both sand and gravel approximately by 10%. O.M.C of clay has turned out to be greater than sand and gravel approximately by 20% and 30%, respectively. Changes in the compaction characteristics can be observed clearly around 30~60% of sand and 30~50% of passing No.200 sieve. It has also been shown that the compaction characteristics related to LL and PL are similar to each other in changes, and that the compaction characteristics become less clear with higher percent of fine grained soil. The compaction characteristics of the artificially created granular materials and field materials have appeared almost similar to each other. $r_{dmax}$ is less approximately by 30% and O.M.C greater approximately by 20% in A compaction than in D compaction. As $r_{dmax}$ and O.M.C become greater, its rate increases.

• Journal of the Korean Geotechnical Society
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• v.27 no.3
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• pp.19-26
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• 2011

Compaction tests have been performed to investigate the compaction characteristics of sands and clays with organic mixture. Weathered granite soil, kaolinite, and granulated carbon were used as the alternatives of sand, clay, and organics, respectively. The soapy water which is a kind of surfactant solutions was also used as water substitute to see the engineering properties changes of each soil. As seen when water was used, the optimum moisture contents increased and the maximum dry unit weight decreased for the soil with surfactants as the percentage of the organic contents increased. Surfactants slightly improved the compaction efficiency at low compactive energy level for the weathered granite soil with organics. As the organic contents increased for clays with surfactants, the optimum moisture contents decreased and the maximum dry unit weight increased. Surfactants slightly improved the compaction efficiency of clays with organics at all levels of compaction energy.

• Journal of the Korean Geotechnical Society
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• v.32 no.2
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• pp.53-62
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• 2016

Among several factors controlling soil compaction, temperature is the factor that varies with region and season. Although earthwork is performed in many projects in the cold regions of the earth, studies on quantifying soil compaction associated with temperature are limited. This experimental study investigates the temperature effect on the soil compaction of cohesionless soil. Jumunjin sand was selected for the tests to represent cohesionless clean sand, which is widely used as an engineering fill at petrochemical projects such as northern Alberta of Canada and Russia. The laboratory test program consists of performing a series of standard proctor tests varying temperature of soil samples ranging from $-10^{\circ}C$ to $17^{\circ}C$. Test results indicate that soil specimen volume expansion occurred from bulking and its range was 0% to 6% with zero above temperature. For increasing temperature from $0^{\circ}C$ to $17^{\circ}C$, water content corresponding to maximum volume (minimum dry unit weight) was decreased and water content corresponding to minimum volume (maximum dry unit weight observed after reaching minimum dry unit weight) was slightly increased with increasing temperature. In zero below temperature, dry unit weight gradually decreased with increasing water content. In this case, no bulking effect was found and soil specimen volume increased due to the higher unit volume of ice.

• The Journal of Engineering Geology
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• v.14 no.2
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• pp.199-210
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• 2004

In this study, the physical and mechanical properties of the weathered shale soils distributed in the Hwasun area have been measured in the laboratory. The physical and mechanical properties of the weathered shale soils in the study area as follows: the specific gravity is 2.66 to 2.68, the liquid limit is 36.39 to 36.92(%), the plastic limit is 18.53 to 19.48(%), the plasticity index is 17.44 to 17.86 and soil classification is CL. The maximum dry unit weight and optimum moisture content as calculated by compaction test is 22.5 to 23% and 1.58 to $1.61t/\textrm{m}^3$, respectively. The result of direct shear testing show that cohesion in saturated and unsaturated conditions increases according to the increase of dry unit weight. Internal friction angle in an unsaturated condition increases with an increase of dry unit weight, but in a saturated condition, it increases after decreasing. When compares with engineering characteristics of tile weathered shale soils in the Daegu area (Kim et al., 1995), specific gravity is found to be similar, but the liquid and plastic limit of soil samples in this study area is slightly higher than those of soil samples in the Daegu area.

• Journal of the Korean Geotechnical Society
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• v.17 no.4
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• pp.27-37
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• 2001

본 연구에서는 지금까지 수행한 건조토 지반에 대한 말뚝의 수평거동 연구의 연속된 연구로서 지반내에 함수비가 존재하는 포화토 및 습윤토 지반에서의 수평거동에 대한 지반내 함수비의 영향성을 평가하고자 함이 목적이다. 말뚝의 수평거동을 고찰하기 위하여 각각 다른 함수비를 갖는 네 종류의 지반과 말뚝의 두부 및 선단 구속조건이 다른 네 종류의 말뚝조건으로 모형실험을 수행하였다. 본 연구에서 1회의 지하수 상승과 하강을 반복하는 모형실험결과에 의하면, 포화토와 습윤토 지반의 수평지지력은 건조토 지반에 비하여 각각 26%~45% 감소와 20%~36%정도 증가하는 것으로 나타났다. 말뚝두부 고정과 선단 자유조건의 경우, 동일 수평변위 1mm에서의 최대 휨모멘트는 건조토 지반에 비하여 25%의 함수비를 갖는 습윤토 지반에서 약 48% 증가하나, 34.06%의 함수비를 갖는 포화토 지반에서는 반대로 68% 감소하였다. 이는 지하수의 존재로 인한 입자간 인력에 의한 유효응력과 겉보기강도의 증가 그리고 단위중량의 증가로 설명할 수가 있다. 지속수평하중에 대한 수평변위와 최대 휨모멘트의 변화를 포화토 및 습윤토 지반에서 관찰할 수 있었다.