• 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.

• Geotechnical Engineering
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• v.12 no.6
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• pp.127-138
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• 1996

The in-situ consolidation behavior of drainage system-installed deposits has three dimensional characteristics. Therefore, for an approximate 2-D plane strain consolidation analysis, it is necessary to convert the 3-D spatial flow of actual cases into the laminar flow simulated by the 2-D plane strain model. . In this paper, in order to properly model the effect of three dimensional characteristics, an equivalent and efficient model has been applied in a finite element technique for the analysis of the drainage system-installed soil deposits. The equivalent two dimensional model involves equivalent permeabilities and drainage widths. To validate the equivalent two dimensional model, three dimensional analyses were per formed by using the ABAQUS program and the results of 3-D analyses were compared with those of the 2-D analyses. By using the proposed equivalent model, one may be able to appropriately predict the consolidation behavior of drainage system-installed soft deposits.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.09a
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• pp.519-526
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• 2010

The construction site for $\bigcirc\bigcirc$ transformer substation was located at a mountain valley. In order to prepare the site, the valley was first filled with crushed rock debris up to 63m. Since the main concern of this project is to minimize differential settlement of the foundation of transformer facilities, dynamic compaction was performed every 7m followed by reinforcement with EMP(Ez-Mud Piling). The EMP is one of bored piling methods, in which a hole is bored by means of air percussion and maintain by injecting Ez-Mud. Then a PHC pile (Pretensioned spun High strength Concrete pile) is embedded and finalized with a hammer. In this study, bearing capacities and long term behavior of a pile installed by EMP were investigated. To achieve these objectives, a series of tests such as static and dynamic load tests were conducted. In addition, a construction quality control standard was proposed based on the test results.

• Journal of the Korean Geotechnical Society
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• v.19 no.1
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• pp.21-29
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• 2003

In this study, practical guidelines to check the possibility of some lateral movement of piled abutment were investigated. In these tests, both the depth of soft clay and the rate of embankment construction are chosen to examine the effect on lateral soil movements. The depth of soft clay layer varies from 5.2 m to 11.6 m, and the rate of embankment construction has two types : staged construction(1m/30days, 1m/15days) and instant construction. Various measuring instruments such as LVDTs, strain gauges, pressure cells, and pore pressure transducers are installed in designed positions in ordo. to clarify the soil - pile interaction and the short and long term behavior f3. piled bridge abutments adjacent to surcharge loads. The validity of the proposed guidelines by centrifuge test was compared with the observed performance by lateral movement index, F(Japan Highway Public Corporation) and modified I index(Korea Highway Corporation). Based on the results obtained, the critical values off and modified I, as a practical guidelines, are proposed as 0.03 and 2.0, respectively.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.03a
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• pp.768-773
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• 2009

Measuring method being applied for off-shore works is performed by using data logger or manual measuring instrument with wiring the cable connected from the sensor up to the position where measuring is allowed.(upper part of embankment or marine structure) Measuring management by using existing measuring method may be acceptable on the condition that the ground deformation volume(vertical, horizontal) is generally minimal and the site condition is good. But loss of measuring instrument, sensor cable failure or cutting is taken place frequently due to significant change of ground behavior caused by an external force change(embankment, excavation) under very soft ground condition(N value below 0-4). In case of the marine works, in particular, loss rate of measuring instrument is highly represented due to the factors of working barge anchoring, constructional interference and natural disaster. In order to solve these problems, measuring management was performed with employing underground wireless system at the immersed tunnel site. Measuring data was obtained freely under the marine environment by using underground wireless communication and cable cutting potential by ground behavior could be reduced. Measuring cost savings and its installation convenience were maximized by way of off-shore tower installation or cabling and by minimizing constructional interference of off-shore working barge. This case of measuring management was accomplished successfully.

• Journal of the Korean Geotechnical Society
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• v.39 no.9
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• pp.25-33
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• 2023

To effectively improve soft soils, it is necessary to perform ground behavior characteristics and stability management through measurement activities when embankment of structures on soft soils is conducted. However, there are many differences between the actual ground behavior and the initial design plan. To address this issue, this study analyzed the measured settlement in the Yeongam-Haenam areas using the Hyperbolic method to predict the settlement based on the measurement data. From the completion time of the embankment in the target area, the final settlement was predicted through the change in the degree of consolidation by the measurement period. Furthermore, the final settlement according to the change in degree of consolidation was compared and analyzed through finite element analysis and field measurement.

• Korean Journal of Agricultural Science
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• v.29 no.2
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• pp.53-66
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• 2002

This study was performed to evaluation the consolidation behavior of agricultural reservoir in the very soft ground. The final settlement prediction methods by Terzaghi, Hyperbolic and Asaoka methods were used to compare with the degree of consolidation estimated by exess pore water pressure. The dissipated excess pore water pressure during embankment construction and peak excess pore water pressure on the completed embankment were suggested for the estimation of the degree of consolidation. It was concluded that the degree of consolidation estimated from dissipated excess pore water pressure was more reliable than that from the peak excess pore water pressure. The stability methods for agricultural reservoir was used to compare and analyze with various condition by limit equilibrium method.

• 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.

• Journal of the Korea Institute of Building Construction
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• v.1 no.1
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• pp.151-159
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• 2001

This study was performed to investigate the effect of time-dependent creep on the deformation. In the analysis, modified Cam-Clay model was adopted to describe the elastic-plastic behavior of clayey soil. In order to consider effect of creep, the secondary coefficient of consolidation $\alpha$ was supplemented to modified Cam-Clay model. To examine the reliability of the program which is developed in this study, the estimated values by this program were compared with the experimental results. The results of the analysis were in good agreement with the observed values in the field.

• Proceedings of the Korean Geotechical Society Conference
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• 2000.09a
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• pp.73-78
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• 2000

The reinforced soil has been widely used for constructing retaining walls and embankment with steep slope. However, the benefits of soil reinforcing are often-restricted by a lack of good quality backfill material. In this study, plane strain compression tests were carried out to study the effects of preloading on the behavior of geosynthetic-reinforced saturated clay. For the unreinforced and reinforced soil, drained and undrained shearing tests were peformed after anisotropic consolidation in a constant strain rate. A preoading test was carried out by preloading, creep, unloading, aging and undrained shearing after anisotropic consolidation(K=0.3, σ'₃=50 kPa). It was observed that a reinforced clay, Kanto loam, can have a great initial secant modulus in undraind condition by well compaction and over consolidation. The results shown that the increasing of drained strength should be used to apply a large preloading in the case of reinforced clay.