• Proceedings of the Korean Geotechical Society Conference
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• 2003.03a
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• pp.663-670
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• 2003

Urban tunnelling need to consider not only the stability of tunnel itself but also the ground movement regarding adjacent structures. This paper present 3-D behavior of adjacent structures due to tunnelling induced ground movements by means of field measuring data and nonlinear FEM tunnel analysis. The results of the analytical methods from Mohr-Coulomb model are compared with the site measurement data obtained during the twin tunnel construction. It was found that the location and stiffness of the structure influence greatly the shape and pattern of settlement trough. The settlement trough for Greenfield condition was different from the trough for existing adjacent structures. Therefore the load and stiffness of adjacent structures should be taken into account for the stability analysis of the structures.

• Proceedings of the Korean Geotechical Society Conference
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• 1999.10a
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• pp.365-370
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• 1999

In this paper, dynamic response analysis on the ground movement applied traffic load by 2D finite element procedure has been studied. In particular, The paper deal with pointing acceleration method that applied AFIMEX Code as like 2D-FLUSH using equivalent linear method. As the result, it is found that dynamic response analysis by pointing acceleration method expressed ground movement by traffic load exactly.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.5
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• pp.1799-1804
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• 2010

In regard to fill loading structures such as bridge abutments and retaining walls on soft ground, the soft ground undergoes excessive deformation, which causes the lateral movement of the ground, resulting in increased risk of much damage. In this study, a centrifuge model test was conducted to check the possibility of lateral movement of a bridge abutment during back filling in a field, and a numerical analysis considering the lateral movement of the bridge abutment under the influence of the counterweight fill method applied during construction was carried out by using MIDAS/GTS as the FEM(Finite Element Method) program. The results of this study showed that the lateral movement of the abutment can exceed the allowable lateral movement value(15mm), and that the counterweight fill method was effective for the stability of the lateral movement.

• Journal of Korean Association for Spatial Structures
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• v.14 no.1
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• pp.69-76
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• 2014

When we excavate an underground to build basement, the ground anchors are needed to prevent collapse of neighboring ground, subsidence and movement. Ground anchor construction required shore sheet piles, wales and struts as to maintain secure excavation. Existing box-type bracket using head part of ground anchor can not be possibly adjustable to the boring angle because the brackets are manufactured with unified angle in a factory. Also, box-type brackets have imperfection and instability caused by inequable force. In this study, a new bracket system is proposed. The bracket's side plate is reinforced and the angle of boring can be controlled. To investigate the structural performance of presented brackets, FEM analysis has been performed by using ANSYS commercial program. As a result, this bracket shows sufficient stability for all angle case and the strength is increased about 24% than existing bracket.

• Tunnel and Underground Space
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• v.7 no.2
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• pp.136-142
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• 1997

The behaviour of ground movement during the construction of two parallel tunnels in weathered zone and soft rock has been investigated. All the influencing factors for the behaviour of twin tunnel such as tunnel size, ground conditions, tunnel depth, pillar width and initial state of ground stresses were examined The results of FEM nonlinear analysis were compared with some of model test results in weathered zone to verify the numerical method. It was found that minimum interference was obtained in the parallel construction case when the twin tunnel distance (pillar width) is just over the twice of tunnel diameter. Guide line for the interference of twin tunnelling has been introduced for the ground of weathered zone and soft rock.

• Journal of Korean Tunnelling and Underground Space Association
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• v.5 no.4
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• pp.313-322
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• 2003

This research work presents 3-D behavior of adjacent structures due to tunnelling induced ground movements by means of field measuring data and nonlinear FEM tunnel analysis. The results of the analytical methods from Mohr-Coulomb model are compared with the site measurement data obtained during the twin tunnel construction. It was found that the location and stiffness of the structure influence greatly the shape and pattern of settlement trough. The settlement trough for Greenfield condition was different from the trough for existing adjacent structures. Therefore the load and stiffness of adjacent structures should be taken into account for the stability analysis of the structures.

• Geomechanics and Engineering
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• v.20 no.4
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• pp.275-285
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• 2020

Excavation usually induces considerable ground settlement in soft ground, which may result in damage of adjacent buildings. Generally, the settlement is predicted through elastic-plastic finite element method and empirical method with defects. In this paper, an analytical solution for predicting ground settlement induced by excavation is developed based on the definition of three basic modes of wall displacement: T mode, R mode and P model. A separation variable method is employed to solve the problem based on elastic theory. The solution is validated by comparing the results from the analytical method with the results from finite element method(FEM) and existing measured data. Good agreement is obtained. The results show that T mode and R mode will result in a downward-sloping ground settlement profile. The P mode will result in a concave-type ground settlement profile.

• Journal of the Korean Geotechnical Society
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• v.24 no.8
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• pp.35-41
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• 2008

Laminar-shear-boxes are widely used to simulate free-field seismic ground response by using a l-g shaking table or geo centrifuge in geotechnical earthquake engineering. This study numerically modeled and compared the ground responses in the free field, rigid box, and laminar shear box by using a 3-D FEM program. It is found from the numerical simulations that the laminar shear box can simulate the free field ground movement more precisely than the rigid box. However, the laminar shear box underestimated the surface acceleration of the free field ground. It also showed low-frequency characteristics probably because the stiffness and inertia effect of surrounding ground are neglected.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.932-939
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• 2005

Recently, the lateral displacement of the passive piles which installed under the revetment on soft ground is very important during the land reclamation work along the coastal line. The revetment on the soft clay develops the lateral displacement of the ground when the revetment loading is exceeded a certain limit. The lateral displacement of ground causes an excessive deformation of under structure itself and develops lateral earth pressure against the pile foundation as well. Especially passive piles subjected to lateral earth pressures are likely to have excessive horizontal displacement and large bending moment, which induces structural failure of pile foundation and harmful effects on superstructure. The subject of study is to investigate the later displacement of pile foundation during the construction of container terminal at the south port of Incheon. Actual field measurement data and finite element method(FEM) by AFFIMEX Ver 3.4 were used to analyze the displacement of pile and the vertical settlement of soft ground. This analysis was carried out at each sequence of construction work.

• Journal of the Korean GEO-environmental Society
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• v.23 no.9
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• pp.25-31
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• 2022

Attaching shelf to retaining structure leads to a decrease in the total lateral earth pressure. This decrease enables the retaining structures to become more stable, to have small displacement, and to exhibit lower bending moments, the relief shelves effects are analyzed using FEM in order to understand how they stabilize cantilever wall in this study. Several models are varied by changing location and width of shelves to realize earth pressure and displacements of retaining wall. The displacement is getting smaller because earth pressure acting on shelf increases as shelves locations are lower and width is longer. The ground settlement variation effects caused by relief shelves are studied also. The ground settlement increases abruptly where shelf location is between of 0.5H and 0.625H, and settlement decreases suddenly where shelf width is between b/h=0.375 and b/h=0.500. The shelf significantly reduces earth pressure and movement of the wall. This decrease in the lateral pressure increases the retaining structure stability.