• Journal of the Korean Geotechnical Society
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• v.23 no.12
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• pp.43-52
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• 2007

This study analyzes the characteristics of creep deformation behavior of weathered granite soils used in road embankments. The creep strain under the unconfined compressive state demonstrated an excellent agreement with the theoretical analysis of the burgers substance. The elastic deformation showed a termination in its characteristics after a long-term period owing to the increase in applied loads. The primary creep strain was 0.0028 and concluded that the deformation completed within $3{\sim}5$ days after applying the loads. Also, the completing time of creep deformation in the embankment soils increased in proportion to the height of embankment soils. The secondary creep strain is about 50% of the primary creep strain.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.2 no.4
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• pp.39-47
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• 1982

Geotextile effects as reinforcement and vertical drain materials are studied through the laboratory model embankments on weak clays. The experiments are carried out in four stages; no woven fabrics between clay-crushed stone boundary, fabrics between boundary with no initial pretensioning of fabrics, and fabrics between boundary with two different initial pretensionings of fabrics. In all stages, vertical drains utilizing non-woven fabrics are installed in the clay layer in square pattern to accelarate the consolidation. The experimental model has plane dimensions of $32cm{\times}330cm$. The height for the clay container is 60 cm. The 47 cm height of crushed stone embankment is constructed over the 50 cm deep clay layer. The time dependent pore pressures are measured utilizing the 8 piezometers installed symmetrically on both sides of the wall at different heights. The time dependent deformations are measured utilizing the LED indicating lamp matrix inserted in the crushed stone embankment and the dialgauges put on top of the clay layer where the crushed stones are not laid. The measurements are carried out for 10 days which is equivalent to the time required for the primary consolidation. Through the experimental study, an analytical procedure is developed to predict the time dependent embankment settlement even if the top of the clay layer is reinforced with woven fabrics. This can be done through measuring the maximum pore pressures developed in the clay layer and comparing with the theoretical maximum pore pressures when no reinforcing fabrics are employed.

• Wind and Structures
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• v.20 no.4
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• pp.509-525
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• 2015

A three-dimensional aerodynamic model and a vehicle dynamics model are established to investigate the effect of noise barrier on the dynamic performance of a high-speed train running on an embankment in crosswind in this paper. Based on the developed model, flow structures around the train with and without noise barrier are compared. Effect of the noise barrier height on the train dynamic performance is studied. Then, comparisons between the dynamic performance indexes of the train running on the windward track and on the leeward track are made. The calculated results show that the noise barrier has significant effects on the structure of the flow field around the train in crosswind and thus on the dynamic performance of the high-speed train. The dynamic performance of the train on the windward track is better than that on the leeward track. In addition, various heights of the noise barrier will have different effects on the train dynamic performance. The dynamic performance indexes keep decreasing with the increase of the noise barrier height before the height reaches a certain value, while these indexes have an inverse trend when the height is above this value. These results suggest that optimization on the noise barrier height is possible and demonstrate that the designed noise barrier height of the existing China Railway High-speed line analysed in this article is reasonable from the view point of the flow field structure and train dynamic performance although the noise barrier is always designed based on the noise-related standard.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.1
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• pp.195-205
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• 2013

This study, using the MCC Model to consider consolidation, estimated the range within which no influences occur from lateral movement and its amount of the foundation pile and abutment on the soft ground. This study performed finite element analyses, with variations on the adhesiveness and internal friction angle, depth of soft clay, embankment height, consolidation parameters, and separation distance between the abutment and embankment. The abutment's horizontal displacement exhibits linear change with a longer separation distance, and changes into an exponential form as the embankment gets closer to the abutment. As the soft clay layer becomes 10 m deeper, the horizontal displacement tends to increase 1.5~3.0 times. However, it decreases at a rate of 0.3~0.95 when adhesiveness is increased by 10 $kN/m^2$ and internal friction angle is increased by $5^{\circ}$. The increase change rate in a lateral movement amount becomes greater if it is closer to the abutment when the abutment separation distance is long. When the distance is short, the change rate of horizontal displacement increases in similar a way, but it tends to be decreasing overall.

• Journal of the Korean GEO-environmental Society
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• v.8 no.5
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• pp.39-46
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• 2007

In this study, the centrifuge tests were performed to investigate the lateral flow behavior and stability of the ground improved by SCP. The centrifuge tests were fulfilled in the case of the back of abutment filled by EPS (case 1) and soil (case 2), and the potentiometer was installed on the abutment and embankment to measure the vertical and horizontal displacement at the top of abutment. As a result, the vertical displacement measured at the back of abutment was maximum 2.1 m, which was about 12% if compared with the height of embankment. In the case of the back of abutment filled by soil, the vertical and horizontal displacement measured at the top of abutment was 10 cm and 1.1 m, respectively, which exceeded the allowable horizontal displacement. On the other hand, in the case of the back of abutment filled by EPS, the vertical displacement of abutment did nor occur and the horizontal displacement was 1.4 cm. Therefore, the effect of SCP improvement with EPS method adopted to prevent the lateral flow and assure the stability of embankment on the soft ground was far superior.

• Magazine of the Korean Society of Agricultural Engineers
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• v.25 no.4
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• pp.29-37
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• 1983

This study was carried out not only to prepare available materials that can be utilized in basic planning of irrigation reservoirs, but also to contribute to the study on countermeasures for reasonable irrigation water development in Korea in the future, through the investigation for the structural characteristics of reservoirs and their change trend by an epoch. During this study 123 sites of sample reservoirs were analysed in their dimensions of physical constituent factors. The physical characteristics and their change trends revealed by this study are summarized as follows: 1. For the irrigation earth dam in Korea the correlation between dam volume (v) and dam height & length (H$^2$L) can be described as the formula of v=1. 434H2L~17, 300 (r=0. 933), from which embankment amount is assumed to be quickly estimated under determined dam height and length of the proposed reservoir. 2. The ratio of dam volume to dam height & length ranges approximately from 0.5 to 3 (1.7 in average), that of storage capacity to dam volume 2 to 10 (8.4 in average), that of irrigation area to full water surface area 5 to 20 (13 in average) and that of catchment area to irrigation area 2 to 5 (4 in average). Though correlation between dam volume and dam height & length is high, that between others is relatively low. 3. Average storage depth ranges approximately from 4m to l0m (6.6m in average), unit storage capacity 0. 4m to 0. 8m (0.54 in average) and shape factor of dam 5 to 20 (10.5 in average). 4. The more recently planned the reservoirs were, the less storage capacity, dam volume, full water surface and dam shape factor they have. 5. The more recently planned the reservoirs were, the larger storage depth and unit storage capacity they have.

• Journal of the Korean GEO-environmental Society
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• v.22 no.8
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• pp.13-19
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• 2021

In the case of construction on soft ground - such as national expressways sponsored by Social Overhead Capital (SOC) - many problems occur due to excessive settlement: therefore, an accurate settlement prediction has a major impact on the selection of improvement methods, project budget and construction period. Most of the settlement prediction methods currently used in projects apply Terzaghi's Theory of One-Dimensional Consolidation which assumes the uniformity of the depth of the soft ground. However, the results of soft ground settlement predictions vary when the target layer is divided into multiple horizontal layers. This study analyzed the change in the consolidation settlement behavior according to the horizontal division of soft ground as well as with different loading height.

• Proceedings of the KSR Conference
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• 2011.05a
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• pp.1774-1785
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• 2011

In this paper, Rigid Reinforced Roadbed(RRR) which is expected to have highly applicability to railroad roadbed, was introduced and field tests results were analyzed. Full scale model with 5m height concerning a single track railroad roadbed was constructed. The model had four different sections, which was to assess the effect of geogrid length, spacing, and connection method on deformation characteristics of RRR. Laser displacement meter, earth pressure cell, piezometer, and strain gauge were installed in order to analyze the behavior of reinforced embankment during construction. Horizontal displacements caused by compaction at each section were 20~30% below the displacement limit that of general reinforced retaining wall, which showed that RRR was very stable structure. Maximum tensile strength of reinforcement was withing 10% of the long-term design strength.

• Proceedings of the Korean Geotechical Society Conference
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• 2000.11a
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• pp.177-184
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• 2000

Geotube is a tube made of geotextile and hydraulically filled with dredged soil. This technological method has been widely used in the advanced countries of the world to build the shore protection embankment. The dredged contaminated sediments from the lake, river, and harbor can be pumped into the geotube by using the hydraulic pump. So, environments effects can be minimized and enhanced by using this method. This paper presents a field test result of a geotube in the land reclamation project for the Songdo New City construction site. The dredged silty clay was dredged by the dredging ship and hydraulically pumped into the geotube. The height of geotube was measured at every filling stage and also measured width and diameter of geotube with the elapsed time. The unit weight of soil and undrained shear strength of filled soil in a tube were measured at the various locations and heights of geotube with the elapsed time. Geotube technique can be effectively implemented for the silty clayey soil with using the dredging ship.

• Journal of Industrial Technology
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• v.33 no.A
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• pp.23-30
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• 2013

Tidal power generation is to produce electrical energy from fluctuations of the ebb and flow in a constructed embankment. More specifically, the sinusoidal variations of tidal flow, along with the periodicity and changes in the height of waves over time make the tidal power generation possible at a certain tidal level. This paper proposes a more practical efficiency test method for tidal power plant generator that utilizes the axis torque changing values rather than the retardation method which is commonly used. The proposed method was compared with the conventional method and the test result shows that proposed method provides a similar accuracy with the conventional retardation method and a better efficiency.