• Earthquakes and Structures
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• v.27 no.1
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• pp.41-55
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• 2024

There are obvious differences between the characteristics of offshore ground motion and onshore ground motion in current studies, and factors such as water layer and site conditions have great influence on the characteristics of offshore ground motion. In addition, unlike seismic response analysis of offshore superstructures such as sea-crossing bridges, tunnels are affected by offshore soil constraints, so it is necessary to consider the dynamic interaction between structure and offshore soil layer. Therefore, a seismic response analysis model considering the seawater, soil layer and tunnel structure coupling is established. Firstly, the measured offshore and different soil layers onshore ground records are input respectively, and the difference of seismic response under different types of ground motions is analyzed. Then, the models of different site conditions were input into the measured onshore bedrock strong ground motion records to study the influence of seawater layer and silt soft soil layer on the seabed and tunnel structure. The results show that the overall seismic response between the seabed and the tunnel structure is more significant when the offshore ground motion is input. The seawater layer can suppression the vertical seismic response of seabed and tunnel structure, while the slit soft soil layer can amplify the horizontal seismic response. The results will help to promote seismic wave selection of marine structures and provide reference for improving the accuracy of seismic design of immersed tunnels.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.587-590
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• 2005

This study investigates the efficient construction scheme of the immersed tunnel focusing on the hydration heat. In this respect, some alternatives in curing, temperature condition and removing of the forms are compared together to meet the required criteria. It is addressed that the strict construction stage analysis considering the placing scheme of concrete is one of the key factors to trace the realistic structural behavior for the hydration heat.

• Journal of Korean Tunnelling and Underground Space Association
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• v.12 no.6
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• pp.429-441
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• 2010

In this study, fire resistance of a fireproof material sprayed upon an immersed tunnel was experimentally evaluated under $HC_{inc}$ and IS0834(duration of 4 hours) fire scenarios. Under $HC_{inc}$ fire scenario, the maximum inner temperatures of a concrete specimen at the depth of 0, 25 and 50 mm from the interface between the structure and the fire-proofing layer were $311^{\circ}C$, $194^{\circ}C$ and $142^{\circ}C$ respectively. Similarly, the corresponding maximum temperatures under IS0834 fire scenario were $332^{\circ}C$, $222^{\circ}C$ and $179^{\circ}C$ respectively. From the results, it was revealed that the two different fire scenarios assumed in this study have almost the same fire capacity as each other in the maximum temperature concept. In addition, a structural analysis of the immersed tunnel under $HC_{inc}$ fire scenario was carried out to verify the effects of the fireproof material on its structural stability. Material loss and deterioration of a concrete specimen without any fire-proofing measure was also experimentally evaluated to obtain input parameters for the structural analysis under such a severe fire scenario. From the results, it was confirmed that the application of fireproof measures to the immersed tunnel is essential for its structural stability even under a severe fire scenario.

• Construction Engineering and Management
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• v.11 no.3
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• pp.29-31
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• 2010

• Computational Structural Engineering
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• v.23 no.5
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• pp.13-16
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• 2010

• Magazine of korean Tunnelling and Underground Space Association
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• v.21 no.1
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• pp.32-48
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• 2019

• Wind and Structures
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• v.5 no.2_3_4
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• pp.347-358
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• 2002

Mean surface pressures and overall wind loads on hemispherical domes immersed in a boundary layer were obtained by numerical simulation. The effects of alternative turbulence models, Reynolds Number and surface roughness were examined and compared with earlier studies. Surface pressures on dual hemispherical domes were also calculated for three wind orientations ($0^{\circ}$, $45^{\circ}$, and $90^{\circ}$) to evaluate flow field interactions. Calculated values were compared to wind-tunnel measurements made in equivalent flow conditions.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.1291-1298
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• 2005

Shotcrete for the support of tunnel can contact with groundwater. The hazardous components in the groundwater cause the corrosion of shotcrete. Also, the hazardous components may deteriorate the engineering properties of shotcrete, such as compressive strength, bond strength, and flexural strength. The more the effect of the hazardous components on the shotcrete may increase, the more the stability of tunnel structure may decrease. It was analyzed to find the hazardous components in the ground water. The uniaxial compressive strength test, XRD, SEM were conducted to evaluate the durability and corrosion of shotcrete. These tests were performed on shotcrete specimens at 2, 4, 8, and 16 weeks. The specimens were immersed in various chemical solutions including hazardous components after the specimens were made at the construction site.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.1689-1692
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• 2008

In this research, these days extension of electric power station plant and new building plan is tending to more bigger size and much more cooling water for discharge, therefore submarine structure for discharge has needed various types and the large one. The domestic power plant was applied to once-through CW system structure that pipe line type, immersed PC-box culvert type and submarine headrace tunnel type of discharge structure. It is possible that the future structure type of submarine discharge is expected by a case research of application and plan.

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 2006.09a
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• pp.113-116
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• 2006