• Journal of the Korean Geotechnical Society
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• v.23 no.7
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• pp.27-36
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• 2007

A model test was performed to evaluate the stability of a new earth retention system with a prestressed wale. For the model test, the dimensional analysis of a full-scaled earth retention system with prestressed wales was performed. Details of the dimensional analysis of the new earth retention system were presented in this paper. Based on the results of the dimensional analysis, the model-scaled earth retention system with a prestressed wale was simulated. The lateral earth pressures on the wall, the lateral deflection of the prestressed wale, the sectional force on members of the prestressed wale system, and the loads of struts were measured during construction simulation. The measured results were evaluated and compared with those of the design criterion. From the measurements, the behavior of this earth retention system was investigated.

• Journal of the Korean Geosynthetics Society
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• v.14 no.2
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• pp.23-33
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• 2015

The earth pressure acting on underground structure was measured by application of the instrumentation system in the subway construction site constructed by the method of cut-and-cover tunnel. The measured earth pressure was compared with the earth pressure obtained from the existed theoretical equation, and the actual earth pressure diagram acting on the underground structure was investigated. As a result of investigation, the vertical earth pressure is mainly affected by the embankment height, and the lateral earth pressure is significantly affected by whether the existence of earth retaining structures or not. The measured vertical earth pressure is very similar to the theoretical earth pressure proposed by Bierbaumer. The measured lateral earth pressure is closed to the active earth pressure proposed by Rankine rather than the earth pressure at rest. The coefficient of earth pressure in soil deposit layer is about 0.35, and the coefficient in soft rock deposit layer is about 0.21. For design and construction the underground structures, therefore, it is reasonable estimation that the lateral earth pressure acting on structures installed in soil deposit layers is an average value between active earth pressure and earth pressure at rest. In rock deposit layers, the lateral earth pressure acting on structure is an active earth pressure only.

• Journal of the Korean Geotechnical Society
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• v.20 no.1
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• pp.83-90
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• 2004

Retaining walls with reinforced earth have been constructed around the world. The use of reinforced earth is a recent development in the design and construction of earth-retaining structure. It is believed that reinforced retaining wall has some advantages which make construction quite simple basically. It wilt take short construction time relatively, comparing, fur example with reinforced-concrete retaining wall. In addition, low price and easy construction will be good attractive points in practical point of view. In this study, five field-tests monitoring data for lateral pressures on geogrid-reinforced retaining wall have been compiled and evaluated. Based on field-tests it is found that horizontal displacements of the facing was measured to be about 0.19∼0.76% and that the maximum tensile strains of reinforcement was evaluated to be about 0.66∼1.98%. The maximum tensile strains, measured from each site, do not reach 5% of the practical allowable strain of the geogrid. And also it is found that the lateral pressure distributions of reinforced-earth retaining wall are close to a trapezoid shape like a flexible retaining wall system, instead of a theoretical triangular shape.

• Journal of the Korean Geotechnical Society
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• v.17 no.6
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• pp.163-171
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• 2001

It is important to pay careful attention to the backfill construction for the structural integrity of concrete box culvert. To increase the structural integrity of culvert good compaction by the dynamic compaction roller with big capacity is as effective as good backfill materials. However structural distress of the culvert could be occurred due to the excessive earth pressure by great dynamic compaction load. In this study, two box culverts were constructed with change compaction materials and construction methods. Two type of on-site soils such as subbase and subgrade materials were used as backfill materials. In most case, dynamic compaction rollers with 11 to 12 ton weights were used and vibration frequency were applied from 2000 to 2500 rpm for the great compaction energy. Backfill compactions with good quality soils were carried out to examine the effect of cushions on dynamic lateral soil pressure. Expanded polystyrene (EPS) and rubber of tire were adapted as cushion materials and they are set on the culverts before backfill construction. This paper presents the main results on the characteristics of dynamic earth pressures. Test result indicates that the amounts of increased dynamic pressures are affected with backfill materials, depth of pressure cell, and compaction condition. The earth pressure during compaction can give harmful effect to box culvert because the value of dynamic earth pressure coefficient $(\DeltaK_{dyn}=\DeltaK\sigma_h\DeltaK\sigma_v)$ during compaction is greater than that of static condition. It was observed that cushion panels of EPS(t=10cm) and rubber(t=5cm) are effective to mitigate dynamic lateral pressure on the culverts.

• Proceedings of the Korean Geotechical Society Conference
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• 1993.03a
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• pp.21-26
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• 1993

Using the well-known FLAC program an analylical parametric study was made to investigate the horizontal and vartical solution zone applied to the mountain water tunnel analysis. In the analyses two different heights(30m, 130m) of overburden soils measured from the center of a tunnel and three different coafflclants of lateral earth pressures(0.25, 0.75, 0.5) were adopted. Also the effected of plliar width between twin tunnels, having two different heighte of overburdon soils as well as different soil conditions, were analyzed.

• 한국지구물리탐사학회:학술대회논문집
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• 2003.11a
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• pp.198-205
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• 2003

We considered the variation of elastic wave velocity due to the anisotropy of rock materials and stress level for acoustic emission (AE) source location in cylindrical rock specimens. Elastic wave velocity and AE were measured for Keochang granite and Yeosan marble under various axial stresses and confining pressures. Partition approximation method was suggested and it was compared with the difference approximation method and the least square method.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.03a
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• pp.1210-1224
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• 2009

The present paper illustrates the outcome of the monitoring of the consolidation behavior of a soft foundation soil under a large submerged sand embankment. Measurements of settlements and excess pore water pressures showed a good agreement with predictions evaluated using the large strain consolidation theory. Soft soil improvement by means of deep mixing has been optimized. Moreover, the principles and developments of underwater geosynthetics applications are discussed.

• Journal of the Korean Geophysical Society
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• v.6 no.2
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• pp.57-69
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• 2003

In this paper the theoretical method to analyse the pore water pressures in the bed under the oscillating water pressure is developed. In the former researches the validity of the theoretical treatment for the one-dimensional problem has been verified. However, the one-dimensional treatment is not sufficient to obtain the precise information concerning the many practical problems. From this point of view, in this study, we derive the fundamental equations for the general three-dimensional sand layer under the oscillating water pressure. The validity of this theoretical method is verified by experiments for the two-dimensional problems.

• Atmosphere
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• v.20 no.3
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• pp.355-366
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• 2010

The tropopause pressure in the Arctic region is calculated by the conventional thermal and dynamical methods using 30-year reanalysis data. The tropopause pressures determined thermally and dynamically both show semiannual cycles with one peak in April and May, and another in October, contrary to the tropopause temperatures. Although tropopause levels are higher both in January and July, the level of the tropopause in January seems to be associated with the stratospheric temperatures while that of July seems to be associated with the tropospheric temperatures. During the 30-year period the most significant trend appears in April, and it is shown that the altitude of the Arctic tropopause has been rising. Although a potential reason for this trend is stratospheric cooling due to ozone depletion, significant tropospheric warming in April is considered to be another reason.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.11 no.2
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• pp.51-64
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• 1991

To evaluate the compaction - induced lateral earth pressure acting on retaining structures such as retaining walls, abutments, culverts, underground walls, etc., a new equation is developed using the newly proposed hysteretic model simulating soil's loading - unloading behavoir under Ko-condition. The lateral pressurds calculated by the new equation are found to agree well with those of field tests previously performed by other researchers.