• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2000년도 춘계학술대회논문집B
• /
• pp.619-624
• /
• 2000

The purpose of present study is to investigate for reducing micro pressure waves generated according to train speeds $(240km/h{\sim}380km/h)$ through tunnels with countermeasures as followings; the hood configuration in tunnel entrance. We developed hoods for tunnel of 0.5 km length in the condition of tunnel cross-section area of $107m^2$ on the slab track. According to the results the maximum micro-pressure wave is reduced by 41.2% for the slit hood installed at the entrance of the tunnel and reduced by 47.7% for the slit hood installed at the entrance of the tunnel and the $45^{\circ}$ slanted portal at the exit of the tunnel

• 한국지반공학회:학술대회논문집
• /
• 한국지반공학회 2006년도 추계 학술발표회
• /
• pp.497-508
• /
• 2006

Busan-Geoje Fixed Link, total length of 8.2km, consist of bridge and immersed tunnel connects Gaduk island, Busan and Jangmokmyon, Geoje, in extension of the $58^{th}$ local road. The immersed tunnel, a total length of 3.7km within Busan-Geoje Fixed Link, was planed first timein domestic but the deep water depth like maximum of 50m with offshore conditions and the 35m thickness of soft clay layer under the immersed tunnel, migth be some problems like the differential settlement during or after works. So it was designed to install SCP(Sand Compaction Pile) column partially to improve the soft ground under the immersed tunnel. In this paper, it is presented to illustrate the design including ground condition under the immersed tunnel, improvement design, upheaval shape and ratio due to SCP test construction.

• Geomechanics and Engineering
• /
• 제21권2호
• /
• pp.207-213
• /
• 2020

Umbrella Arch Method (UAM) often employed in the tunnel construction under poor rock mass conditions in Korea. Insertion of steel pipes at the periphery of the tunnel and infiltration of grouts along the pipes into the rock masses increases tunnel stability. There are two major effects of grouts expected at the tunnel face: 1) increase of face stability by enhancing the frictional resistance of discontinuities and 2) decrease of permeability along the rock masses. Increase of resistance and decrease of permeability requires a certain curing time for the grout. In Korea, we require 24 hours for curing of grout, which means no progress of excavation for 24 hours after infiltration of grouts. This step delays the tunnel construction sequences. To eliminate such inefficiency, we propose MTG (Method for Tunnel construction using Grouting technology), which uses extended length of steel pipes (14 m) compared to conventional pipe roof method (12 m). The merit of MTG is the reduction of curing time. Because of the approximately 2 m extension of the length of steel pipe, blasting can be done after infiltration of grouting. For this paper, we conducted experiments on the shear strength behaviors of grout infilled rock joint with elapsing of curing time and blasting induced vibration. The results show that blasting induced vibration under MTG does not influence the mechanical features of grout material, which indicates no influence on the mechanical behaviors of grout, contributing to the stability of tunnels during excavation. This result indicates that MTG is a cost effective and fast construction method for tunneling in Korea.

• 한국ITS학회 논문지
• /
• 제11권6호
• /
• pp.145-154
• /
• 2012

본 논문은 고속도로 터널구간을 대상으로 교통사고특성을 다각적으로 분석하여 다양한 독립변수를 선정하고 종속변수를 건, 건/km, 건/백만대km로 다양화하여 다중선형회귀모형을 개발하였다. 그리고 개발된 모형들은 상호 비교 검토하여 최종적으로 교통사고영향요인으로 구성된 신뢰성 있는 교통사고예측모형을 결정하였다. 교통사고예측모형은 모형의 $R^2$, F값 등 검정통계량 수준, 다중공선성, 잔차분석 등 모형검증과정이 수행되었고 터널구간의 교통사고특성 반영여부 등을 검토하여 최종적으로 터널길이에 따라 총 2개의 모형을 선정하였다. 선정된 종속변수는 ln(건/백만대km)이며, 독립 변수는 연평균일교통량(AADT), 종단구배, 터널높이로 구성되었다. 추정모형은 RMSE, MAE를 이용하여 예측한 값과 실제 관측값과의 차이를 분석하여 터널구간의 교통사고를 설명하는데 적합한 모형으로 파악되었다.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2007년도 춘계학술대회 논문집
• /
• pp.1770-1773
• /
• 2007

Fire accident in tunnel is one of the most critical railway accidents, together with overturning of train by derailment and train crash. Tunnel structures contribute to minimize the cost and time of transport, but in case of railway fire accident occurring bring serious damages of human life caused by narrowness of shelter, poisonous smoke and high temperature raised at the inside of tunnel. For that reason, at the beginning of plan of tunnel, the optimum design for rescue of passengers is needed. For the detail and most suitable design for rescue of passengers, many tunnel designer substituted simulation program for mock examination by its high cost and effort. In this study, simulation program techniques, such as Fluent and Simulex, are applied for verifying the rescue design of passengers reduced the risk when fire accident occurred at tunnel utilizing of case study for planned railway tunnels shows 1,245m length in Iksan-Sili area.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2004년도 추계학술대회 논문집
• /
• pp.234-239
• /
• 2004

Recently, the tunnel structures are increasing. And the tunnels are to be large diameter tunnel and long. Therefore, inspection, repair, and maintenance of tunnels are an extremely important part of infrastructure management, with particular technical and safety considerations arising from the very nature of underground construction. To inspect surface state of tunnels, concrete structures, it must generally use method of conventional visual inspection, but this method is very not objective. To measure the width, length, position, direction of a crack, it is very difficult, when the tunnel is long span and high rise. Thus, to make up for this demerits, in this paper is proposed the Tunnel Scanning System that we can check conditions of the tunnel structures quickly, detect the detailed data objectively, count automatically the width of a crack by the original software and follow the trend of long tenn changes in the condition of a tunnel.

• 한국유체기계학회 논문집
• /
• 제18권1호
• /
• pp.5-10
• /
• 2015

The "Ondong tunnel" is not used now where is one of the tunnels in the Janghang line which is from Cheonan to Iksan. The length of the tunnel is 214 m. The location of the fire source is center of the tunnel and the pool fire with heptane is for the fire source. Tests are carried out for the various fire sizes, the height and obstructed/open condition of the fire source. Temperature on the top of the tunnel is measured. Even if the fire size is same, the maximum temperature on the ceiling of the tunnel for the elevated fire source is very larger than the maximum for the ground fire source. As the fire size is lager the maximum temperature on the ceiling is higher. These test results can be very useful for design and guidelines of fire detectors in tunnels.

• 대한안전경영과학회지
• /
• 제25권2호
• /
• pp.129-138
• /
• 2023

This study attempted to analyze the comparative advantage in terms of disaster safety costs in verifying the effectiveness and economic feasibility of the high-performance water-bulwark system in the pole tunnel, which was recently promoted as a part of the acceleration of vehicles. The tunnel to be analyzed was divided into a short tunnel(Anyang, Cheonggye) and a long tunnel(Suraksan, Sapaesan). As a result, it was analyzed that 25% of the improvement effect would occur if one lane was secured by applying the Water-Bulwark System. It was analyzed that this is because the time value cost, which accounts for a large proportion of the traffic congestion cost of short tunnels and pole tunnels, differs depending on the congestion time and traffic volume, not the length of the tunnel.

• 한국재난정보학회 논문집
• /
• 제4권2호
• /
• pp.10-27
• /
• 2008

When the ground is excavated adjacent to the existing tunnel, which is loaded by the surcharge on the ground surface, the tunnel stability would be very sensitive to the deformation of the ground induced by the horizontal displacement of braced wall. The stability of the existing surcharged tunnel could be controlled by pre-loading on the braced wall. In this paper, it was investigated, if it would be possible to keep the existing surcharged tunnel stable by preventing the horizontal displacement of a braced wall by imposing the pre-loading during the ground excavation. For this purpose, large scale model tests were performed in a scale 1/10 at the test pit which was 2.0m in width and 6.0m in height and 4.0m in length. Isotropic test ground was constructed homogeneously by wet sand. Model tunnel was constructed in the test ground. Surcharge was loaded on the ground surface above the tunnel. During the tests, the behavior of model tunnel and model braced wall was measured. Numerical analyses were also performed in the same condition as the tests. And their results were compared to that of the model tests. Consequently, the effect of a surcharge could be compensated by imposing the pre-loading on the braced wall. The existing tunnel and the braced wall could be kept stable by preventing the horizontal displacement of the braced wall through pre-loading, although the tunnel is surcharged.

• 한국터널지하공간학회 논문집
• /
• 제3권2호
• /
• pp.3-12
• /
• 2001

본 논문은 절리암반 터널의 안정성 해석을 위한 2차원 개별요소모델링방법에 대한 개선방안을 제안하였다. 먼저, 절리군과 터널의 상대방위를 고려하여 터널단면상에서 불연속거동이 가능한 절리군을 구별하는 기준을 제시하였다. 이 기준에 따라 불연속거동이 가능한 절리군은 개별요소(암석블록)의 변이 되도록 하고 그 외 절리군은 암석블록의 탄성특성을 보정하는 방법을 제시하였다. 또한, 주어진 절리의 기하학적 특성에 대해서 절리의 방위편차와 유한길이를 고려한 복잡한 모델과 절리의 평균방위와 무한길이를 고려한 단순한 모델의 특성을 분석하였다. 그 결과, 후자의 모델이 일관성 있는 터널의 국부적 파괴양상과 명료한 암반의 불연속거동을 보여줌으로써 터널설계목적에 적절함을 확인하였다.