• Journal of the Korean Geotechnical Society
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• v.16 no.1
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• pp.243-250
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• 2000

The mechanical behavior of the underground box culvert constructed by the open cut method depends mainly on the earth pressure acting on it. In this study, the earth pressure on the underground box culverts constructed by the open cut method during and after the construction sequence was numerically analysed by using FLAC. The results are compared with those of the Marston-Spangler's theory, silo theory, and the model tests. The results showed that the vertical earth pressure on the upper slab of the box structure was not uniform. It was as large as the overburden in the middle part of the slab but was smaller or larger than that at its end part depending on the slope of the excavation, the depth of the cover, and the width of the side refill. The horizontal earth pressure on the side wail was much smaller than the earth pressure at rest and grew nonlinearly with the depth.

• Economic and Environmental Geology
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• v.2 no.3
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• pp.58-67
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• 1969

Songgwang lead zinc mine is located in about 12km to the north-east of Jeonju City. Geology of the mine and its visinity is consisted of Jeonju series belonged to so-called Okcheon system, Seodaesan tuff formation, Silla series, and the quartz porphyry intruded into these formations. Jeonju series comprising 3 formations; that is, of Sadaeri, Sindong, and Girinbong. Jeonju series is generally distributed in southern part of the area, striking NNW, and diping NE $30^{\circ}$, or NW $30^{\circ}$. It is deformed to form synclinorium and anticlinorium plunging to the north with low angle. In the northern part of the area, Jeonju series was cut by Sinpeongri-fault of NEE direction near Sinpeongri. In the north side of the fault, it is overturned and shows NEE or NWW strikes and NW $60^{\circ}$ dips. At the west of Songgwangri, it is cut by 3 thrusts; the two are almost parallel each other, and the third oneis manifested by the fact that the lower black shale zone thrusted over the upper limestone. Songgwangri thrust, so named, is a post-mineral fault and its plane represents a premineral slip plane. Enrichment of are took place along the bedding plane or fissure parallel to it, as seen in adit No. 1 or No. 2 along the floor of the thrust, and along the sheared zone or the brecciated zone oblique to the plane near the thrust in crystalline limestone of Sindong formation as observed in the underground levels of inclined slope. Ore minerals are chiefly zincblende, galena, pyrrhotite, arsenopyrite, acompanied pyrite and chalcopyrite, and contain Au and Ag. In earlier stage of mineralization, the limestone was recrystalized, and sulphide minerals were enriched in the· permiable zone said above by pyrometasomatism, and in later stage the limestone was affected chloritization and sericitization. However hydrothermal replacement was weak, so that enrichment did not took place. It seems that minerallizing materials came up through the premineral slip plane and injected, and replaced the limestone in permiable zone said above with sulphide are minerals. Then Songgwangri thrust took place and, the lower black shale zone thrusted upon crystalline limestone.

• Tunnel and Underground Space
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• v.15 no.5 s.58
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• pp.359-368
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• 2005

In case the overburden of a tunnel is too low to adopt NATM, cut and cover method generally can be chosen as alternative. However, in tunneling some area with very low or no overburden between two mountains, the cut and cover method requires additional construction of a couple of tunnel portals and the maintenance of portal slopes until backfilling is completed. As a solution for this problem, increasing the tunnel overburden by raising the ground level can be effective. This paper presents the case study for tunneling at C240 site in Taiwan High Speed Railway(THSR) in which soil-cement filling method was used for pre-banking before tunnel excavation. Cement content of filling material was $2\~4\%$ and thickness of filling a round was $130\~250\;mm$. The stability evaluation for the soil-cement slope and concrete lining of low cover tunnel was conducted by numerical analysis.

• Journal of the Korean Geotechnical Society
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• v.17 no.6
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• pp.111-121
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• 2001

Rockfall protection fences are used for diminishing rockfall damage in roads side slopes. In order to install the fences in effective way, the conditions of rock slopes and total predicted impact energy of fa11ing rock should be considered. However, the fences have been constructed without any consideration for lithology, height and slope angle of rock slope in Korea. In addition, the information about the performance of the protection fences, which should be evaluated by in-situ test or laboratory test in order to check out the practical use in the field, is not available. Therefore, in design manual for the rockfall protection fence, the specific details for the installation of this type of fence are not provided yet. The full sized rockfall in situ test was carried out for the calculation of falling energy of rock and the evaluation of the maximum energy absorbing capacity of fence. For this test, the rock slopes whose heights are about 20 m and dip angle of 65 degree, have been chosen. This is because those geometries are mean height and slope angle of most road cut slopes along Korean national highway. Based on the preliminary simulation procedure, four different sizes of concrete ball (0.7, 1.3, 2.3 and 4.3 ton) were prepared and flour different types of protection fence were constructed. The results of this test provide information about the maximum energy absorbing capacity of the fence, kinetic energy of rockfall and restitution coefficient, and these results can be utilized in the establishment of rockfall fence design and construction manual.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.18 no.3
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• pp.97-107
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• 2015

Research was initiated to investigate a vegetation characteristics of the species of ground cover plants mixed with herbeceous and woody plants on a cut slope. 4 different ground cover plants (Miscanthus sinensis var. purpurascens, Pennisetum alopecuroides, Festuca arundinacea and Zoysia japonica) were seeded at the same rate of $10.0g/m^2$ with herbaceous plants (Lotus corniculatus var. japonicus, Dianthus sinensis, Aster yomena, Chrysanthemum zawadskii and Coreopsis drummondii L) at the total seeding rate of $7.5g/m^2$ and native woody plants (Lespedeza bicolor Turcz, Indigofera pseudo-tinctoria and Albizzia julibrissin) at the total seeding rate of $7.5g/m^2$, respectively. This experiment was treated with 3 replications on a randomized block design. Data such as surface coverage rate(%), the germinating number, plant height and visual quality were analyzed. There were no statistic differences observed in the soil hardness and the soil moisture content while a significant difference was observed in the surface coverage rate and the germinating number. The surface coverage rate and the germinating number were significantly high in the Pennisetum alopecuroides plot when compared with the Miscanthus sinensis var. purpurascens plot, the Festuca arundinacea plot and the Zoysia japonica plot, respectively from the viewpoint of ground covers. Especially, the surface coverage rate was considerably low in the Festuca arundinacea plot. However, the surface coverage rate and the germinating number were no statistic differences observed in this treatment from the viewpoint of herbaceous and woody plants. Also, both of the plant height and visual quality were high in the Pennisetum alopecuroides plot when compared with the Miscanthus sinensis var. purpurascens plot, the Festuca arundinacea plot and the Zoysia japonica plot, respectively. We concluded that Pennisetum alopecuroides was the optimum plant from the treated ground covers mixed with native woody and herbaceous plants for the balanced emergence from the viewpoint of the ecological slope vegetation.

• Journal of the Korean Geotechnical Society
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• v.21 no.5
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• pp.93-101
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• 2005

The formation of slopes is unavoidable under the special circumstance of Korea where $7%$ of the whole area are composed of mountains and civil engineering projects such as road and site developments are increasing with industrial development and horizontal expansions of urban area. Stability of slopes is one of quite important issues under special meteorological characteristics that over two-thirds of annual average rainfall is concentrated in summer season and the localized torrential downpour is getting more frequent recently. As a result of these circumstances, partial slope failures by debris flow of the high water content soils occur frequently in cut soil slopes. In this case of debris flow slope failure, slope declination method is selected fur the stable recovery because it is impossible to recover entirely by existing recovery methods. Seeding or special grass planting methods are followed separately without exception. The method by which entire recover with bigger stability ratio would be possible and grass planting work would be done simultaneously is developed. For debris flow failure slopes, this study secured the safety of slopes by preventing the inflow of rainwater and scour using geosynthetics-reinforced embankment, and created nature-friendly slopes by planting trees on the slopes.

• Journal of the Korean GEO-environmental Society
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• v.11 no.12
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• pp.47-56
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• 2010

The construction of new roads and the consistent extension of already-existing roads or the line-shape revision of those roads are increased with the governmental investment to SOC facilities currently. Accordingly, the road cut slopes are in the trend of rapidly increasing. As the road slope has increased, a lot of human and property damages has entailed consequently and in the local case, numerous studies have carried out aiming at minimizing this damages caused by the rockfall and landslide. In general, standard falling rock prevention facility has employed for most of the local road slope based on "Guide for Installation and Management of Road Safety Facilities" published by MLTM(the Ministry of Land, Transport, and Maritime Affairs) but profound doubt has raised as to whether this rockfall prevention facility would function properly enough to prevent rockfall efficiently without any damages in case of actual occurrence of rockfall. In addition, it is a reality that in most cases, such work is relied on overseas technology as a whole as the local technical level is low and in case of rockfall prevention net, it is judged that a study on rockfall prevention net that is able to endure more powerful rockfall energy is required as the problem including net bursting is taken place as a result of enough bearing force being failed to be demonstrated due to its partial weak point(not uniformly made). Under this background, in this study, three kinds of model depending on mesh size of expanded metal that is considered to have an adoptability as rockfall prevention net, as target are selected and characteristics depending on mesh size of expanded metal is intended to be researched through a pull-out test performance by using pull-out test equipment rockfall prevention net.

• Korean Journal of Environment and Ecology
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• v.37 no.5
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• pp.337-346
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• 2023

Although wildlife bridge are built as a way to reduce habitat fragmentation caused by road construction, there is still a lot of debate about their effectiveness. Monitoring methods such as footprint traps and camera traps are used evaluate the effectiveness of wildlife bridge, but there is a limit to evaluate of effectiveness. In this study, the degree of use the wildlfe bridge was surveyed by striped field mouse that is likely use the wildlife bridge and surrounding as a habitat with capture-mark-recapture method.(Apodemus agraius). The distance and route of movement were identified by connecting the capture points, and the environmental factors on the use of the wildlife bridge implemented a generalized linear model(GLM) with the capture number of captured as a dependent variable. Consequently of capture, no individuals crossing the wildlife bridge, striped field mouse use the wildlife bridge as a habitat.The environmental factors affecting the use of mice were vegetation cover(1~2m, 2~8m, over 8m), vegetation construction, maximum diameter at breast height were positively correlated and slope was nagatively correlated. In conclusion, it is expected that the effectiveness of the wildlife bridge will be further improved by planting shrubs and trees and preventing high slope and cut slope increasing the utilization of the rat, such as being used as a food source in the ecosystem.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.10 no.2
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• pp.1-15
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• 2007

A variety of revegetation methods are being utilized and developed. However, most of revegetation methods used on highway slopes in Korea are based on foreign-introduced plant varieties to stabilize road surfaces and to administer afforestation for surface covering at an earlier phase. Therefore. it results in various problems. such as failure to achieve harmony with the surrounding vegetation and 10 cause re-denudation of slopes as the foreign-in introduced plant varieties wane out from 2~3 years after hydro-seeding, etc. In addition, some of the revegetation plants seeded in the earlier phase grow excessively high, thus causes successional problems, such as to inhibit the invasion of the secondary vegetation from the surrounding areas, etc. Therefore, in this study, 160 slopes located in the nationwide express highways have been investigated and analyzed in order to produce basic data for restoration of ecological environment in slopes created on a long-term basis by investigating and analyzing locational characteristics of cut and filled slopes in express highways, status of revegetation methods, characteristics of soil and plant-ecological environment. 1. Investigation on cut and embanked slopes in express highways was carried out in the total of 160 locations, which include 108 cut slopes and 52 embanked slopes. As a whole, the most frequently used revegetation method was seed spray, which was found to be used in the total of 55 target slops investigated. 2. Planting method of Wistaria floribunda applied to some of the blasted rock zones was found to cause damages as Wistaria floribunda trailed up the surrounding vegetation and the secondary invaded trees. In order to prevent this, this method must be used only in the lowest parts of large-sized slopes. Also, it will be required to administer continuous management and maintenance in the areas already planted with this plants. 3. The areas of blasted rock and ripping rock slopes were applied with coir net (net + seeding) method. However, many of these areas failed in achieving ground covering. Most areas where revegetation was in progress, they were covered with Eragrostis curvula(Weeping lovegrass) only. In areas with soil, such as decomposition of granite, where afforestation is difficult. In this slopes, soil base must be improved by hrdroseeding with thin-layer vegetation base application methods in order to achieve success in afforestation with native plants. 4. Woody species, rather than herb species, are more helpful in stabilization of slope surfaces. Therefore, it is important to be able to grow and protect woody species on highway slopes. Growth of woody vegetation is most largely influenced by soil depth. Thus, when hydro-seeding woody plants, it is recommended to apply at the upper layer of the slopes, which is capable to sufficiently provide the fundamentals required in plant growth.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.6 no.4
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• pp.296-301
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• 2005

This study was conducted to get the basic data on an effect of food waste compost for rock cut-slopese vegetation. Two foreign cool-season grasses and native plants were used for this experiment. Cool-season grasses were Festuca ruba and Lolium perene, Native plants were Amorpha fruticosa, and Indigofera pseudo-tinctoria. Amorpha fruticosa, Indigofera psendo-tinctoria, and Lolium perenne decreased in germination rate and plant height at NaCl concentrations of $0.4\%$ or over suddenly. Festuca rubra occurred to the sudden growth hindrance at NaCl concentrations of $0.2\%$ or over. Amorpha fruticosa and Indigofera pseudo-tinctoria appeared for germination of $45\%$ at all experiment plots. Lolium perenne increased in plant height as trial rate of food waste compost was abundant. Ground cover rate was the highest in Mixture III by $89.3\%$ and was fluctuated from $47.0\%$ after 30 days to $64.1\%$ after 45 days in Mixture 1. Descending order of ground cover rates in 4 treatments was Mixture III, Mixture IV, Mixture II, and Mixture I. As the growth