• Journal of Korean Tunnelling and Underground Space Association
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• v.8 no.1
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• pp.21-30
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• 2006

In case of an urban tunnel, the displacement of ground base controls the tunnel design because it is built on shallow and unconsolidated ground many times. There are more insufficiency to describe the ground movement which coincides in the measured result of the situ because the design of an urban tunnel is dependent on the method of numerical analysis used to the existing elastic and elasto-plastic models. We studied about the predict ion for the ground movement of a shallow tunnel in unconsolidated ground, mechanism of collapse, and settlement. Also this paper shows comparison with the existing elastic and elasto-plastic model using the unlinear analysis of the strain-softening model. We can model the real ground movement as the increasement of ground surface inclination or occurrence of shear band by using strain-softening model for the result of ground movement of an urban NATM tunnel.

• Korean Journal of Applied Biomechanics
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• v.16 no.1
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• pp.119-128
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• 2006

This study was performed to see ground reaction force with different soccer studs with twelve players in Human Performance Laboratory(University of Calgary). Running speed was $4.0{\pm}0.2m/sec$ in straight running as well as vcut running. By using four different kinds of shoes; three different pairs of soccer shoes and one pair of jogging shoes, I reached a conclusion as following. In case of right and left ground reaction force, on the assumption that the positive magnitude of power is inversion and the negative is eversion, vcut running did not occur any inversion, which in the aspect of kinetic mechanics, thought to be decelerating movement. Because when eversion happens, it arises component force of power on heading direction about 8.6 times more than in the movement of straight running. In case of front and rear ground reaction, on the assumption that the positive magnitude of power is suspension power and the negative is propulsion, vcut movement is thought to be decelerating movement in the aspect of kinetic mechanics. Because on heading direction, this movement occurs component force of power about 1.8 times more suspension and 2.2 more propulsion than in the straight running movement. In case of vertical ground reaction, on the assumption that the first peak is the magnitude of power in impact and the second peak is the magnitude of power in active, we judged that the straight running movement performed more efficiently than the vcut movement in the aspect of kinetic mechanics. On the next study, I suppose that vcut running would make up an interesting subject in the aspect of improving kinetic performance ability.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.1802-1807
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• 2004

When a construction company builds a high structure, many piles should be driven into the ground by a hammer whose weight is 7,000 Kg in order to make the ground under the structure safe and strong. So, it is essential to determine whether a pile is penetrated into the ground enough to support the weight of the structure since ground characteristics at different locations are different each other. This paper proposes a visual measurement system for pile rebound and penetration movement including vibration using a high-speed line-scan camera and a specially designed mark to recognize two-dimensional motion parameters of the mark using only a line-scan camera. A mark stacking white and black right-angled triangles is used for the measurement, and movement information for vertical distance, horizontal distance and rotational angle is determined simultaneously

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.3
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• pp.1359-1369
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• 2012

In the case of using pile foundation to support bridge abutments on soft ground, the soft ground often causes serious troubles such as lateral movement of bridge abutments by lateral surcharges. In this paper, we investigated and measured the amount of strain of a bridge abutment in the south-western part of Korea. To check the stability and possibility of lateral movement of the bridge abutment, we used the four analysis methods and compared those results; lateral movement index, index for decision of lateral movement and infinite element analysis method. We performed soil and ground tests to fine the causes of the strain and lateral movement. After reviwing several types of repair methods, we suggested the anker reinforcement method along with surcharge process method as a proper repair and rehabilitation of the bridge abutment. Our investigation by through the infinite element analysis method confirmed the effectiveness of the anker reinforcement method allong with the surcharge process method.

• Journal of Korean Tunnelling and Underground Space Association
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• v.14 no.5
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• pp.485-501
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• 2012

This study aims to experimentally investigate ground settlement and ground movement around the square pipe by its penetration in sandy ground. A series of laboratory model tests were carried out with a small-scale auger equipment for penetration of a square pipe as well as a newly designed test box with a sand raining equipment. From the experiments, it is shown that a square pipe induces ground movement evenly around it in a low overburden condition. However, as the overburden becomes higher, ground movement by a square pipe is concentrated mainly above it. Especially, horizontal strain above the square pipe was mainly dominated by its penetration. In addition, sand surface movement is the smallest in case of the dimensionless penetration rate equal to 0.2. When its penetration rate of the square pipe is fixed, the rotation speed of auger controls surface movement whether it is settlement or heaving. Therefore, the selection of an optimal dimensionless rate for the square pipe is a key design factor to minimize ground settlement in a trenchless construction.

• Proceedings of the Korean Geotechical Society Conference
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• 2001.10c
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• pp.103-122
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• 2001

For prediction of ground movement per the excavation step, observational results of ground movement during the construction was very different with prediction during the analysis of design. step because of the uncertainty of the numerical analysis modelling, the soil parameter, and the condition of a construction field, etc. however accuratly numerical analysis method was applied. Therefore, the management system through the construction field measurement should be achieved for grasping the situation during the excavation. Until present, the measurement system restricted by ‘Absolute Value Management system’only analyzing the stability of present step was executed. So, it was difficult situation to expect the prediction of ground movement for the next excavation step. In this situation, it was developed that ‘The Management system TOMAS-EXCAV’ consisted of ‘Absolute value management system’ analyzing the stability of present step and ‘Prediction management system’ expecting the ground movement of next excavation step and analyzing the stability of next excavation step by‘Back Analysis’. TOMAS-EXCAV could be applied to all uncertainty of earth retaining structures analysis by connecting ‘Forward analysis program’ and ‘Back analysis program’ and optimizing the main design variables using SQP-MMFD optimization method through measurement results. The application of TOMAS-EXCAV was confirmed that verifed the three earth retaing construction field by back analysis.

• Proceedings of the Korean Geotechical Society Conference
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• 2002.03a
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• pp.263-270
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• 2002

During deep excavation, changes in the state of stress in the ground mass around the excavation and subsequent ground losses inevitably occur. These changes in the stress and ground losses are reflected on surrounding ground in the form of ground movements, which eventually Impose strains onto nearby structures through translation, rotation, distortion, and possibly damage. A substantial portion of the cost of deep excavations in urban environments is, therefore, devoted to prevent ground movements. Prediction of ground movements and assessment of the risk of damage to adjacent structures has become an essential part of the planning, design, and construction of a deep excavation project in the urban environments. This paper presents excavation-induced ground movement characteristics as well as important issues related to excavation-induced building damage assessment.

• Journal of Korean Port Research
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• v.12 no.2
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• pp.337-348
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• 1998

Since 1970s, though many effective construction methods have been established to solve soft ground problems which had occurred in the off shore land reclamation and on shore highway construction, lateral movement of structure on soft ground is still a big problem to engineers. In this study an applicability of criteria for determining the lateral movement of the structure in soft ground is examined and most measured data is obtained from 140 bridge abutments in highway construction sites. Characteristics and effectiveness of existing methods that used for deciding amount of lateral movements of abutment are analyzed using the obtained data. From the analysis, a proper method to prevent lateral movement is proposed. This method is confirmed on several case histories which were constructed on marine clay.

• Journal of the Korean Geotechnical Society
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• v.22 no.8
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• pp.13-24
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• 2006

A site investigation has been performed for bridge abutments constructed on soft ground, which are deformed laterally by backfill. As the result from the evaluation of lateral movement in bridge abutment, the foundation piles were not considered as the passive pile at the design stage and the period for soft ground improvement was not proper. In order to prevent lateral movement of bridge abutment, the pile slab is proposed as a countermeasure. This method can effectively prevent the lateral flow of soft ground, since the overburden surcharge due to backfill on soft ground would be effectively delivered to bedrock through the piles in soft ground. The instrumentation system is designed and installed to investigate the behavior of bridge abutment on soft ground reinforced by pile slab. The instrumentation results show that pile slab effectively resists to the lateral movement of bridge abutment due to backfill. Also, the surcharge loads due to backfill are transmitted to the bedrock through piles. It confirms that the pile slab effectively resists to the lateral movement of bridge abutment due to backfill and the applied design method is reasonable.

• Journal of the Korean Society of Industry Convergence
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• v.8 no.3
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• pp.161-168
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• 2005

This study is analysis for adjacent structures and ground movement by deep excavation work. Underground Inclinometer has shown that deformation of increment is minor within to allowable limit. According to the measurements result of slope and crack for adjacent structures, a detached house showed bigger than hospital structure to deformation of increment. Variation of underground water level didn't effect so much to ground and adjacent structures movement because underground water flows in rock and didn't give the water press to propped walls. Measurement data of strut variation is within tolerance limit. Because excavation site's wall was strengthened suitably. This study will contribute in establishment of measurement standard and information-oriented construction during deep excavation in multi-layered ground including rock masses.