• Journal of Korean Tunnelling and Underground Space Association
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• v.18 no.3
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• pp.319-329
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• 2016

Underground structures such as subsea tunnel having large section should be stable against seismic loads. In general, underground structures show more stable behavior due to the limited dynamic motion and force, and considerable energy dissipation; however, severe damage was reported from recent earthquakes. Therefore, more sophisticated and analytic approach is required to investigate the seismic response of underground structure like subsea tunnel. In this study, seismic analysis of virtual Honam-Jeju subsea tunnel are performed. Consequently, stresses and forces of tunnel lining increased at fractured and/or weak rock zones. Stresses and forces of tunnel lining also increased at large section under axially deformed condition; however, decrease under transversely deformed condition.

• Journal of Korean Tunnelling and Underground Space Association
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• v.13 no.5
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• pp.413-430
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• 2011

Consideration on the explosion resistant design of infrastructure has increased in the recent years. The explosion load is caused by gas explosion or bomb blast. In this study an analytical model is developed, whereby the tunnel structure is divided in several elements that are schematized as single degree of freedom mass-spring-dashpot systems on gas explosion. Using this simple model a sensitivity analysis has been carried out on tunnel structure design parameters such as explosive peak pressure, duration of the load, thickness of structure, burial depth. Finite element method was used to investigate the dynamic response and plastic zone of a tunnel under gas explosion. And it was found from the comparison of the analysis results that there are slight differences in the response of the intermediate wall between the single degree of freedom mass-spring-dashpot model and FEM.

• Tunnel and Underground Space
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• v.16 no.4 s.63
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• pp.347-356
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• 2006

We analyzed case studies doing in-depth inspection of tunnel to maintain safety of existing tunnel in constructing new tunnel near to a existing tunnel with single track. Futhermore, We accomplished in-depth inspection of existing tunnel and numerical analysis. We suggested remedies to security safety of existing tunnel. We applied line drilling and pre-large hole boring method not to have an effect on existing tunnel and convinced the safety of existing tunnel from blast-vibration and blast-noise of numerical analysis. We planed to install basset system to measure displacement of existing tunnel according to excavating new tunnel.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.1585-1592
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• 2008

산업사회의 발전에 따라 사회 기반시설분야도 복잡다양해지고 특히 도시기능이 활발해지면서 지금의 도심지에는 지하철, 상수도, 하수도, 전력구, 통신구, 지하보차도, 지하상가, 지하주차장 등 여러 가지 용도의 지하공간이 요구되고 있으며, 이러한 지하 구조물을 축조하는데 있어 도로상에 차량 증가로 인한 교통 혼잡이나, 지하매설물의 장애로 인하여 기존의 개착식 공법으로 시행하지 못하고 지하터널공사로 시행하는 경우가 빈번하다. 기존 국내 외 터널공법 관련문헌과 현재 사용되는 터널공법의 실제 시공에 관한 정보를 수집하여 장 단점, 시공시 주의사항, 적용조건등의 조사내용을 바탕으로 RPS 공법을 고안하였다. 소규모 지하구조물을 구축하기 위한 RPS 공법은 출발갱내에서 상부에 파이프 루프를 시공한 후 광폭 유압 패널이 장착된 철제 선도관을 추진시켜 선도관을 원압잭에 의하여 압입한 후 P.C. 콘크리트 구조물을 거치하고 원압으로 압입 추진토록 하였다. 또한, 대규모 지하구조물 축조시에는 구조물 예정상단부에 지반조건에 따라 파이프 루프공법 또는 소구경 Semi-Shield 공법을 이용하여 루프를 시공함으로써 상부의 침하를 방지하고, 측벽은 광폭유압 패널을 이용하여 여굴의 최소화 및 곡선부 시공을 용이하게 하였다.

• Journal of Korean Tunnelling and Underground Space Association
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• v.21 no.1
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• pp.93-113
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• 2019

The behavior of the 3 hinged precast arch structure was investigated by comparing field measurements with numerical analyses performed for precast lining arch structures, which are widely used for the open-cut tunnel. According to the field measurements, the maximum vertical displacement occurred at the crown with upward displacements during the backfilling up to the crown of the arch and downward displacements at the backfill height above the crown. The final crown displacement was 19 mm upward from the original position. The horizontal displacement at the sidewall, which had a maximum horizontal displacement, occurred inward of the arch when compacting the backfill up to the crown and returned to the original position after completing the backfill construction. According to the analysis of displacement measurements, economical design is expected to be possible for precast arch structures compared to rigid concrete structures due to ground-structure interactions. Duncan model gave good results for the estimation of displacements and deformed shape of the tunnel according to the numerical analyses comparing with field measurements. The earth pressure coefficients calculated from the numerical analyses were 0.4 and 0.7 for the left and the right side of the tunnel respectively, which are agreed well with the eccentric load acting on the tunnel due to topographical condition and actual field measurements.

• Magazine of korean Tunnelling and Underground Space Association
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• v.19 no.3
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• pp.13-22
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• 2017

• 방재와보험
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• s.111
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• pp.6-11
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• 2006

인명피해를 넘어 터널 내부의 설비와 구조물의 파손에 이르는 피해정도가 대형화되는 추세이다. 이에 장대화되고 있는 국내 도로터널의 현황 및 방재설비 기준에 대한 문제제기를 통해 효율적 방재시스템 구축과 화재시 안전기준의 개정을 살펴봄으로써, 직.간접적인 피해를 최소화하는 노력이 필요하다.

• Journal of Korean Tunnelling and Underground Space Association
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• v.7 no.3
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• pp.219-226
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• 2005

The result that analyze for 6 years a groundwater influx quantity of total 60 catch-pit established in subway line 5 appeared with $0.77m^3/min$. When comparing design approaches of the catch-pit with design approaches of the box structure $2m^3/min$ and the tunnel structure $3m^3/min$, it is found that it has a surplus. Red sedimentation substance contains large portion of Fe. The earth retaining structure of a tunnel and groundwater containing more portion of Fe than other area rue the major factor of this substance. In case of white sedimentation substance, the most frequently founded ingredient is CaO, which is occurred in case grouting injection materials for ground reinforcement is transmitted into a tunnel system by ground water. This substance is doesn't affect safety of a tunnel.

• Journal of Korean Tunnelling and Underground Space Association
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• v.14 no.2
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• pp.107-116
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• 2012

The experiment was performed to analyze the intersectional ventilation efficiency by intersection structure and Jet Fan in network-form road tunnel. For this, the size of real road tunnel was reduced by 1/45. To apply traffic inertia force when driving, blower fan was used to form an airflow in model tunnel and the intersectional efficiency was also investigated by measuring the speed at local point of the tunnel. To improve the reduction of ventilation caused by the structure character, Jet Fan was installed to optimize ventilation efficiency in tunnel.

• Explosives and Blasting
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• v.21 no.4
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• pp.11-21
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• 2003

An experimental study was carried out in order to reduce the period and cost of construction of Missiryung tunnel, which is a relatively long one 3.6 km long. An allowable vibration level for curing concrete was established based on the extensive case studies done over the world. and assessment was performed on the possibility of constructing concrete structures like lining during tunnel blasting. Attenuation relationships were obtained by processing more than 130 measurement data from a series of tunnel blasting in the site. A Guideline for safe construction work was suggested. To verification, low small concrete blocks with a constant standoff distance were installed in the floor of the tunnel After the blocks were exposed to blast vibrations for 28 days, compressive strength tests were performed on 20 specimens taken from the blocks. It was shown that the suggested guideline was appropriate for the safe construction work at the site.