• Title/Summary/Keyword: rock-soil

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The Effects of the topographical, Soil and Meterological Factors on the Tree Height Growth in the Pinus thunbergii Stands (지형(地形), 토양(土壤) 및 기상인자(氣象因子)가 해송(海松)의 수고생장(樹高生長)에 미치는 영향(影響))

  • Son, Yeong Mo;Chung, Young Gwan
    • Journal of Korean Society of Forest Science
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    • v.83 no.3
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    • pp.380-390
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    • 1994
  • This study was conducted to investigate the effects of the topographical factors (16 items), physico-chemical properties of soil (13 items) and meteorological factors(9 items) on the height growth of Pinus thunbergii stands along the coastal area in Korea. According to the coefficients by partial correlation analysis in total area, it was found that tree height growth was considerably affected by local topography, soil hardness, soil B-horizental depth, effective soil depth, soil moisture, parent rock, soil texture, and etc.. And the soil factors were available $P_2O_5$, total nitrogen, base saturation, exchangeable $Ca^{{+}+}$, and etc.. In partial correlation analysis, annual relative humidity, annual precipitation, index of aridity, and etc. were found to be the most important factors influencing on tree height growth of Pinus thunbergii stands. In conlusion, the topographical, soil and meteorological factors have multiplex influence on the tree height growth in the Pinus thunbergii stands. They promise to provide the basis of improving not only the selection of suitable sites and the management of soil fertilizer but also the estimation of growth and yield. Hence these results would be used successfully for the design in the scientific forest working plan.

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Construction Characteristics and Physicochemical Properties of Soil Layers from Baekje Dongnamri Site in Buyeo, Korea (부여 동남리 백제유적 출토 토층의 물리화학적 성질과 제작특성)

  • Kim, Ae Ra;Lee, Chan Hee;Kim, Ran Hee;Bok, Mun Kang
    • Journal of Conservation Science
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    • v.29 no.3
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    • pp.209-221
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    • 2013
  • This study is to interpret the construction characteristics and the provenance of soil layers from the Dongnamri site in Baekje Kingdom of Buyeo, Korea. The soil layers is divided into present age layer, Baekje layer and lower part layer, and the soils formed in the Baekje Kingdom period is divided into the Baekje 1st layer and the Baekje 2nd layer according to temporal intervals. The soil layers gradually becomes darker in color and higher in mineral content towards the lower part layer. However, the particular distinction between layers of the soils could not be identified. Additionally, the soil layers show a similar characteristics of mineralogy and geochemical evolution regardless of the layers. This indicates that the sites were made with weathered soil from an identical bed rock, and the site show a similarity to the surrounding soil, indicating its possibility of being the original materials. However, through the analysis of particle size, the first and second Baekje layers occurred that these layers were formed by setting up the soil with high content of sand on the bottom and stacking the soil with high content of silt on top of it.

Changes of Soil Properties in Black Locust(Robinia pseudoacacia L.) Stand and Adjacent Stand (아까시나무(Robinia pseudoacacia L.)조림지와 인접 임분의 토양특성 변화)

  • Jung, Sung-Chul;Huh, Tae-Chul;Joo, Sung-Hyun
    • Current Research on Agriculture and Life Sciences
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    • v.21
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    • pp.39-47
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    • 2003
  • The object of this study was to analyze influence which Black locust afforestation affected to soil, to research change of soil environment of Black locust planted stand and adjacent stands through comparative analyzing physichemical property of soil of them. It was investigated that the soil texture of Black locust planted stand and the adjacent stands was mostly SL. and LS. According to this result I could know that transformation of soil texture by vegetation easily happened because transformation soil texture results from the parent rock. I could ascertain that difference existed between Black locust planted stand and the other stands in soil pH and Carbon content of planted stand of Black locust pH, contents of Available $P_2O_5$ Carbon, Total Nitrogen. In other words, pH and Carbon content of Black locust planted stand were lower than that of Oak forest, higher than that of Pine forest. These results showed that Black locust was which fix nitrogen. I could infer that Black locust afforestation made forest soil fertilized. In soil of Black locust planted stand and the adjacent stands, statistical value appeared highly in pH and existed in content of Carbon, Total nitrogen, too. And high interrelationship appeared in the order of pH, C/N Ratio, CEC, Total nitrogen content was in each stands. I suppose that the trespassing extent of Black locust to Oak forest and Pine forest which are adjacent to planted stand of Black locust is different because of low pH, lackness of Available $P_2O_5$ Carbon, and what not.

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A Study on the Applicable Methods of Investigation for Cutting Slope Design (깍기 비탈면 설계에서의 지질조사 기법의 적용성 분석)

  • Lee, Su-Gon;Choi, Kyeong-Chim;Kim, Jae-Heun
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.9 no.1
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    • pp.100-111
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    • 2006
  • This study was carried out to increase the efficiency of site investigation through the evaluation of the applicable methods of investigation for cutting slope design. In an effort to find out the applicability of the method employed during the slope investigation, some tests were carried out on 6 subjects i.e location of weak zones, characteristics of discontinuities, distribution of strata, in situ tests for geo-technical properties, laboratory test and estimation of weathering. The method was highly applicable and produced expected results during the test of weak zones, discontinuities and distribution of strata. In order to apply the method to in- situ test for geo-technical properties and laboratory test on soil and rock slope, a statistic analysis of the existing data were required in advance. However its design applicability on rock slope was good although actual cases of application were not many due to limitation of the cases for investigation. The method was frequently referenced but not actually applied for anti seismic design test and estimation of weathering.

Spectral Shape in Accordance with the Magnitude and Distance of Earthquakes and Its Effect on Multi-DOF Structures (지진의 규모와 거리에 따른 스펙트럼 형상과 다자유도 구조물에 대한 영향)

  • Kim, Jin Woo;Kim, Dong Kwan;Kim, Ho Soo
    • Journal of the Earthquake Engineering Society of Korea
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    • v.24 no.1
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    • pp.49-57
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    • 2020
  • In this study earthquake records were collected for rock conditions that do not reflect seismic amplification by soil from global earthquake databases such as PEER, USGS, and ESMD. The collected earthquake records were classified and analyzed based on the magnitude and distance of earthquakes. Based on the analyzed earthquakes, the design response spectrum shape, effective ground acceleration, and amplification ratios for each period band are presented. In addition, based on the analyzed data, the story shear force for 5F, 10F, 15F, and 20F were derived through an analysis of the elastic time history for multi-DOF structures. The results from analyzing the rock earthquake record show that the seismic load tends to be amplified greatly in the short period region, which is similar to results observed from the Gyeongju and Pohang earthquakes. In addition, the results of the multi-DOF structure analysis show that existing seismic design criteria can be underestimated and designed in the high-order mode of short- and medium-long cycle structures.

Applicability Estimation Compaction Method of Embankment using LWDT and Geogauge (LWDT와 Geogauge를 이용한 성토지반의 다짐관리 현장적용성 평가)

  • Lim, Seong-Yoon;Song, Ho-Sung;Ryu, Hee-Ryong
    • Journal of The Korean Society of Agricultural Engineers
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    • v.58 no.4
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    • pp.85-95
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    • 2016
  • PBT (Plate Bearing Test) is a commonly used compaction estimation used to provide basal support for embankments. This study presents the results from experimental evaluations PBT, LWDT (Light Drop Weight Tester) test and Geogauge test with embankment materials which consist in sandy soil, crushed stone and rock. The results of this study indicate that the regression analyze results (r) from test results between Young's modulus and $k_{30}$, $E_v$ are 0.385 and 0.111~0.496, estimated very lack of correlation. The Geogauge is frequency vibration from machine to underground. Geogauge can not measure to accuracy test results when it is used on ground of the rock or crushed stone. The regression analyze results (r) from $E_v$ and Dynamic modulus are 0.502~0.847, different estimated by calculate method, as it were, when calculate $E_v$, least square method are appeared more accuracy than gradient of secant.

Estimation of Absorbing Capacity from Rockfall Protection Fences (도로 낙석방지울타리의 낙석지지능력 평가 연구)

  • Hwang, Young-Cheol
    • Journal of the Korean GEO-environmental Society
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    • v.3 no.4
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    • pp.59-66
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    • 2002
  • Designs for rockfall protection systems must consider rock and soil types, the angle of the slope, conditions on top and the toe of the affected area. Rockfall protection fence is installed to block for falling rock from cut slopes and this is one of the most common rockfall protection measures. The capability of the fence is provided that sum of capability of poly vinyl chloride coated wire mesh, steel support and wire rope respectively. But in some case, the rockfall protection fence was not supported rockfall energy less than total capability of the fence through the full scale rockfall tests. Therefore, the objectives of this paper are to indicate the problems of fence capability and to improve the design specifications for the fence.

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Running Safety Analysis of Railway Vehicle Systems for Ground Vibration (철도 차량의 지반진동에 의한 주행안전성 평가)

  • Choi, Jun-Sung;Jo, Man-Sup;Lee, Jin-Moo
    • Tunnel and Underground Space
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    • v.16 no.4 s.63
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    • pp.288-295
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    • 2006
  • In this study, dynamic behavior of the vehicles is analyzed, while the track is subjected to lateral vibrations due to earthquake and blasting load. A computer program(WERIA, Wheel Rail Interaction Analysis) is used, which can simulate dynamic responses of vehicles subjected to lateral vibrations. The analysis considers two types of vehicles: I.e. power cars of KTX and Busan subway train. It can also consider the interaction with sub-structures such as tracks and soil. The creep force module is considered, and the running safety of railway vehicles subjected to earthquake and blasting loading is studied. Based on the results of this study, the running safety of the vehicles can be confirmed against lateral vibration.

Case of slope stability in weathered metamorphic rock (풍화된 변성암 사면의 안정대책 사례)

  • Kim, Jae-Hong;Park, Chal-Sook;Jeon, Je-Sung;Hong, Won-Pho
    • Proceedings of the Korean Geotechical Society Conference
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    • 2008.03a
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    • pp.1400-1405
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    • 2008
  • Execute surface of the earth geological survey for stability analysis of stealing cutting sides and investigated wide area nature of soil structure. Inflected DIPS that measure discontinuity's direction that develop to slope and is slope stability a wide use program for Stereographic Projection Method analysis that utilize geometrical correlation of stealing four sides and discontinuity surface. It is principle that angle of internal friction that is basis element of stability estimation applies direct shear test result on joint side, Examination is impossible by case execution, suppose by 30 angles that apply more conservatively in base rock slope sides usually and achieved analysis. When analyze, consider discontinuity's various adult that develop in research slope, after conduct first each discontinuity different assay falling into fault, joint, executed stability estimation which synthesize whole discontinuity data. When ailment element is recognized as analysis result, wished to present stability countermeasure way of most suitable to take into account of execution, stability, economic performance.

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Mechanics of the slaking of shales

  • Vallejo, Luis E.
    • Geomechanics and Engineering
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    • v.3 no.3
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    • pp.219-231
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    • 2011
  • Waste fills resulting from coal mining should consist of large, free-draining sedimentary rocks fragments. The successful performance of these fills is related to the strength and durability of the individual rock fragments. When fills are made of shale fragments, some fragments will be durable and some will degrade into soil particles resulting from slaking and inter-particle point loads. The degraded material fills the voids between the intact fragments, and results in settlement. A laboratory program with point load and slake durability tests as well as thin section examination of sixty-eight shale samples from the Appalachian region of the United States revealed that pore micro-geometry has a major influence on degradation. Under saturated and unsaturated conditions, the shales absorb water, and the air in their pores is compressed, breaking the shales. This breakage was more pronounced in shales with smooth pore boundaries and having a diameter equal to or smaller than 0.060 mm. If the pore walls were rough, the air-pressure breaking mechanism was not effective. However, pore roughness (measured by the fractal dimension) had a detrimental effect on point load resistance. This study indicated that the optimum shales to resist both slaking as well as point loads are those that have pores with a fractal dimension equal to 1.425 and a diameter equal to or smaller than 0.06 mm.