• Proceedings of the Korean Geotechical Society Conference
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• 1990.10a
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• pp.9-24
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• 1990

Most tunnels in soft soils in urban areas are constructed by shield tunnelling method for environmental reasons. Ground surface settlements are caused by shield tunnelling so that auxiliary measures are often required. Simple methods to predict ground surface settlement are given. The use of the slurry or the earth pressure balance shield machine and the application of new methods of grouting with computer aided operation control systems decreases the ground surface settlement to 3 mm. The construction cost of tunnels is almost identical whichever type of shield machine is employed according to a statistical investigation.

• Journal of KSNVE
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• v.5 no.1
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• pp.67-73
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• 1995

In earth moving construction equipment used for rough and dangerous works, seat suspension system is the only means for reducing the vibration transmitted to the operator. Thus ISO(International Organization for Standardization) 7096 suggests a recommendation for the vibration characteristics of the seat suspension system in order to protect the human beings from excessive vibrationl. In this research, a new mechanical type seat suspension system is designed and a mathematical model, effective design parameters of the seat suspension system are determined and concept design strategy is presented.

• 한국지구물리탐사학회:학술대회논문집
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• 2011.10a
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• pp.109-112
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• 2011

• Proceedings of the Korean Geotechical Society Conference
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• 2008.03a
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• pp.521-532
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• 2008

Supporting system design and construction management for the soft and hard rock layers with fractured zones are very important theme for the safety of temporary retaining wall, surrounding ground and structures in the urban deep excavation for the construction of subway, railway, building etc. The prevailing design method of supporting system for the soft and hard rock layers in the deep excavation is mostly carrying out by simplification without proper consideration for the characteristic of rock discontinuities. Therefore the behaviors of rock discontinuities and fractured zones dominate the whole safety of excavation work in the real construction stage, serious disaster due to the failure of temporary retaining wall can be induced in the case of developing large deformations in the ground and large axial forces in the supporting system. This paper introduces examples of deep excavation where the soft and hard rock layers with fractured zones were designed to be supported by shotcrete and rock bolt, deformations of corresponding ground and supporting systems in the construction period and increments of axial force in the upper earth anchors and strut due to the these deformations were investigated through detailed analysis of measurement data, the results were so used for the management of consecutive construction that led to the safe and economical completion of excavation work. The effort of this article aims to improve and develop the technique of design and construction in the coming projects having similar ground condition and supporting method.

• Journal of the Korean Society for Railway
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• v.13 no.5
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• pp.521-527
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• 2010

The Paved Track is applied to reduce maintenance cost of conventional line. The Paved Track could be used in all types of lines including earthwork, bridge, tunnel and turnout sections. In case of earthwork section, the construction joint is the most critical factor to track durability. The construction joint does not affect to the track structure directly, but the gap due to discontinuity of slabs may affect to the long-term serviceability. To evaluate this problem, the accelerated track test has been performed on the construction joint and the middle part to of the real scale Paved Track. The purpose of this test is that evaluate the vulnerability of construction joint section comparing the trends of settlement and earth pressure under repeated loads of construction joint with those of the middle slab part.

• Proceedings of the Korean Geotechical Society Conference
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• 1994.09a
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• pp.1-59
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• 1994

The design and construction of strutted and anchored sheet pile walls in soft clay are reviewed based on experience gained mainly in Singapore during the last 10years where mainly strutted sheet pile walls diaphragm walls, and contiguous bored piles are used. It is important to consider in the design the high lateral earth pressures acting on the sheet piles below the bottom of the excavation when the depth of the excavation is large compared with the shear strength of the clay. The strut loads and the maximum bending moment in the sheet piles can in that case be much higher than indicated by a conventional analysis. Different methods to increase the stability have been investigated. With jet grouting, embankment piles and excavation under water it is possible to reduce significantly the maximum bending moment, the strut loads, and the settlements outside the excavated area as well as the heave within the excavation.

• Proceedings of the Korean Geotechical Society Conference
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• 2003.06a
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• pp.45-52
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• 2003

Construction and extension of road by industrialization are increasing. According to this, construction of large cutting slope is increasing. Therefore, many methods for slope stability by this are applied. Failure happens according to dip and dip direction of slope. It is actuality that is connoting unstable element. This slope include coaly shale. Stability of slope failure this study takes place by road extension running examination for stability property calculate. Use this and examined stability about stereographic projection and wedge failure. Apply suitable reinforcement countermeasure about unstable cutting slope and analyzed stability. Wish to consider effective and robust processing plan of great principle earth and sand side securing stability. Hereafter with these data, is going to utilize in reinforcement and failure prevention.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.353-364
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• 2011

This paper presents the ground behaviour of shield TBM lunching area during excavation. In order to perform this study, a scaled model test was carried out in the 1/45 scale for a field tunnel in practice where the tunnel had about 7.8 m diameter at Seoul Metro Line 9 construction site. The test to simulate earth pressure balance (EPB) shield TBM tunnelling at the lunching area was conducted with the developed small scaled shield TBM machine. Measurements were performed during simulation of excavation for total jacking thrust force, ground displacements and pressures. Based on the analysis of simulation results, the stability of ground was verified and evaluated. In particular, the suitable reinforcement range and methods are also suggested. In addition, these results are useful for engineers and technicians to select suitable and serviceable machine operation parameters and reduce environmental influence at all stages of tunnel construction.

• The Journal of Engineering Geology
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• v.16 no.1 s.47
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• pp.97-107
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• 2006

Or this study, prevailing design and construction methods of dam under various unfavorable conditions are summarized. for example, foundation treatment with large scale alluvium site or weathered rock mass, dam constructing techniques with unfavorable topographic conditions are studied for the better understanding of relating engineers. Also, zoning by using weak rocks and sand-gravel fill techniques are summed up.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.380-383
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• 2004

The coarse and fine aggregates that make up the majority of concrete are resources. But, the raw naturals that make up concrete are our earth's resources and there is not a replenishable stock. Also industrial waste and life waste leaped into a pollution source. Therefore, as construction continue, quarries are exhausted and new sources must be discovered. The purpose of this paper is to investigate an application of recycled coal ash plastics in the construction field. The study examined the physical and mechanical properties of recycled coal ash plastics aggregate. In the results, although the absorption and specific gravity of SLAs increases slightly as the fly ash content increases, the compressive strength and modulus of elastic of concrete made with SLAs remains relatively constant when mortar type and volume fraction are also held constant. These values are always lower than natural-weight aggregate concretes.