PURPOSES : This study aims to deduce the appropriate interval of cross passage for small vehicle exclusive roads within urban underground roads to ensure safety.
METHODS : This study evaluated evacuation safety by fire and evacuation simulations. The simulation was applied to a passenger-caronly urban underground road, which was performed in the entry/exit section with a gradient of 6.0% and the mainline on level grade. The values of the variables for the simulations were determined to be close to the actual situation based on of the statistics and the results of previous studies. In the simulation scenario, the cross passage interval was visible. The evacuation safety was evaluated by comparing the “evacuation completion time” and the “smoke diffusion time.” Evacuation safety can be desirable when the evacuation completion time is shorter than the smoke diffusion time.
RESULTS : According to the results of the simulation, the desirable cross passage interval is 180 m for the entry/exit sections with a 6% gradient in passenger-car-only tunnels. This criterion may be prolonged to an interval of 210 m and a width of 0.9 m for the construction reduction, based on the results of the statistical analysis.
CONCLUSIONS : According to the results of this study, the risk indices of the “Small Vehicles Road Tunnel Fire Safety Facility Installation and Management Guidelines” may be supplemented by the tunnel class and the gradient of the entry/exit section. In addition, the guideline may provide an improved interval of evacuation cross passage and the width of the cross passage door by the safety index.
PURPOSES : In this study, the luminance of night road markings was measured in a tunnel of length 200 m or less. The purpose of the project is to evaluate the consistency of night road markings.
METHODS : In this study, field measurements were conducted to achieve the purpose of this study. Five tunnels with lengths of less than 200 m were selected to measure the luminance value of the road markings. The analysis of the difference in road markings between the inside and outside points of the tunnel and the analysis of alternative tunnels and points were used to assess the consistency of road markings in tunnels.
RESULTS : The average luminance of the tunnel’s night road markings was 9.7, and the standard deviation was 3.0. The analysis of variance for the tunnel and point indicated that the p-value was less than 0.05 and was inconsistent.
CONCLUSIONS : In conclusion, consistency was assessed by measuring the luminance value of the short tunnel of length 200 m in the Cheongju Sangju Expressway, and it was confirmed that the luminance of the road markings was not consistent with the tunnel and point. Finally, it is necessary to control night lightings on roads outside the tunnel or adjust lighting facilities in the tunnel to enhance the consistency of luminance.
PURPOSES : The purpose of this study was to investigate the behaviors of the middle slab in a double-deck road tunnel subjected to construction equipment loading from such as a concrete pump car, concrete transmixer, and lifting crane.
METHODS: The major construction processes of a middle slab include concrete placement, concrete transportation, and lifting of materials near the emergency passageway section. During the concrete placement, the middle slab is subjected to construction loading due to the presence of the concrete pump car and fully loaded concrete transmixer. During the concrete transportation, the middle slab is subjected to loadings from both the fully loaded and empty concrete transmixer. The emergency passageway section of the middle slab is subjected to crane loading during lifting work. The magnitudes and geometries of these construction loadings are determined and the stresses and deflections of the middle slab under these loadings are analyzed using finite element models of the middle slab. The behaviors of the middle slab under the design truck loadings are also analyzed to compare the results with those under construction loadings.
RESULTS : The stresses and deflections of the middle slab under construction loadings are comparable to those under the design truck loadings. Higher stresses can be observed when the concrete transmixers cross paths at the expansion joint section of the middle slab. The behaviors of the middle slab under the construction loadings during concrete placement are very similar regardless of the section types of the middle slab such as the normal, expansion joint, and emergency passageway sections.
CONCLUSIONS : When the middle slab is designed, the construction loadings should be considered to determine the primary design loads and to verify the usability of a variety of construction equipment.
The objective of this study is to analyze the behavior and failure mode of the brackets that support middle slabs in the double-deck tunnels by conducting laboratory experiments. In the double-deck tunnels, the middle slabs are supported by the brackets connecting to the tunnel lining. The brackets are subjected to the loads due to the weight of middle slabs and traffic moving on the middle slabs. Since the damages of brackets are directly associated with the safety problems such as falling down of middle slabs, the appropriate design of brackets is one of the most important factors when designing double-deck tunnels. In this study, the reinforcement design of concrete bracket was performed based on the concrete structure design guide, and the load capacity was evaluated by conducting laboratory loading tests. A small scale concrete bracket specimen was fabricated using the scale factor of 0.5. The reaction wall is normally needed to simulate the tunnel lining in this kind of test; however, two brackets were attached symmetrically to a column, which was assumed to be tunnel lining, to be able to conduct the tests without using the reaction wall. When the bracket specimen was fabricated, the lining part was fabricated first and after curing of the lining part, two brackets were fabricated at the same time at both sides of the lining part. In the tests, the loads were applied to both brackets simultaneously using a loading frame and the displacements were measured at different locations. The main behaviors of the bracket systems such as the vertical displacements of brackets and the displacements at the interfaces between the brackets and lining were measured and the horizontal displacements of the specimen were also measured at the bottom of the lining part to confirm if there was any slip or rotation of the specimen during the tests. The experimental analysis results showed that the initial damage of the specimen was observed at the interface between the bracket and lining with appearing the gap and the failure of the specimen was reached with cracking in the brackets. The load capacity (safety factor) of the bracket specimen to the initial damage based on the design load was 2.5 and to the failure was 3.3.
In this study, Determine weight of damages, which were excerpt from analyzing inspection reports in Road Tunnel, using AHP technique. The result of weight of damages using AHP. is a slight difference from current weight one. So we need to think about this conclusion as new weight of damages in road tunnel.
In the Gangwon province, severe freezing damage to road tunnels are occurred due to freezing condition such as snowfall, cold waves and icing. As a result, serious damage occurs on the lining and road surface of the tunnel entrance and exit. Therefore, it is necessary to develop appropriate mitigation methods to protect damage to people and property by freezing. In this paper, we introduce that the trend of research for reducing the freezing damage and the required performance to be secured for the maintenance of road tunnels in cold region and the future research plans.
The airborne chlorides environment by de-icing salts of the Suam road tunnel in motorway were examined. It was found that higher airborne chlorides were detected inside road tunnel than outside. Therefore, there is a need to appreciate that RC structures inside tunnel might be exposed to salt attack environment.
In the Gangwon province, severe freezing damage to road tunnels are occurred due to freezing condition such as snowfall, cold waves and icing. As a result, serious damage occurs on the lining and road surface of the tunnel entrance and exit. Therefore, it is necessary to develop appropriate mitigation methods to protect damage to people and property by freezing. In this paper, we introduce that the trend of research for reducing the freezing damage and the required performance to be secured for the maintenance of road tunnels in cold region and the future research plans.
The airborne chlorides environment by de-icing salts of the Suam road tunnel in motorway were examined. It was found that higher airborne chlorides were detected inside road tunnel than outside. Therefore, there is a need to appreciate that RC structures inside tunnel might be exposed to salt attack environment
In the winter season, a many problems such as water leaks, icicles, etc. has occurred by freezing phenomenon at the road tunnels. Therefore, in order to reduce property damage caused by cold environment, it is necessary to establish a mechanism of freezing and thawing of tunnel structures. In this study aims to introduce the method for freeze damage reduction and suggest the plan for practical use of it.
In this study, discover vulnerable elements of Road Tunnel by database and analyzing inspection reports. And provide the data so that can explore ways to improve and feedback.
Based on the study of chloride migration coefficient and hydration heat evolution, it was found that the use of ternary blended cement was effective to achieve desired service life and minimum crack index. On the other hand, a high level of compressive strength is required for marine concrete mix design.
최근 도심지와 산간지역에 설치되는 도로터널의 경우 터널개소의 증가와 장대화로 화재 사고가 점차 증가되고 있어 터널의 방재시설 강화가 요구되고 있다. 하지만 터널화재 발생시 대규모 인명피해가 발생될 수 있는 연기질식사 방지를 위한 연구는 부족한 실정이다. 본 연구에서는 화재발생시 연기확산을 차단하여 질식사 최소화 및 대피시간을 확보 할 수 있는 에어커튼 시스템을 개발하였다. 에어커튼 시스템은 방재설계 사례를 기준으로 시뮬레이션(CFD)을 통한 최적화 방안(분사각도, 분사량 등)을 도출하였으며, 실내 Lab Test 및 실제 도로터널서 화재실험을 실시한 결과 차연성능을 발휘하였다. 이론적/실험적 검증을 통한 에어커튼 시스템 도입을 통하여 도로터널의 인명피해를 최소화 할 수 있는 새로운 방재시설로 발전되길 기대한다.
The newly-developed self-mobilizing space frame system is the equipment possible to adjust frame width and height per various road tunnel sizes. Main purpose of this system is to maintain road tunnels without blocking lanes. Therefore, it does not affect traffic and completes maintenance work quickly as compared to current method.
산악터널과 달리 도심지 지하도로는 대부분 평야지대에 위치하고 충적층이 두껍게 분포하고 있으며 특히 터널 입․출구부는 병렬터널로 분기되는 지점인 동시에 하향굴착을 하는 관계로 터널 시․종점의 위치선정에 따라 공사비에 미치는 영향이 매우 크게 된다. 또한 병렬터널의 필라폭(PW)은 지하 보상비와 직결 되기 때문에 병렬터널의 안정을 확보하면서 동시에 최소의 필라폭(PW)으로 터널을 계획하여야 한다. 국내 도로터널의 필라폭(PW)은 일반적으로 1.5D(D: 터널 최대폭)를 기준으로 하며 일부 터널의 경우 입․출구부 극히 한정된 구간에서만 1.5D(D : 터널 최대폭)이내의 필라폭을 적용한 사례가 있으나 보상비 문제가 아닌 선형계획측면에서 불가피하게 발생한 사례들이다. 본 논문은 NATM형식으로서 국내최초 도심지 지하도로 설계사례를 통해 선형 계획단계에서부터 지하 보상비 및 지반특성을 함께 고려하여 적정 필라폭을 설계한 사례를 소개하고 도심지 병렬터널의 적정 필라폭 결정방법에 대해 기술하였다. 적정 필라폭 결정은 설계 및 시공사례 분석과 수치해석을 통한 강도 감소법과 강도/응력비 방법을 이용하였으며 터널간 초근접으로 인해 필라의 안정성이 불량한 터널 입․출구부는 안정성 확보를 위한 보강 방법을 제시하고 수치해석을 통해 안정성을 확인하였다.
본 연구는 준설선을 이용하여 가덕수도를 횡단하며 준설공사를 하는 동안에 선박들의 안전한 통항방안을 제시하는 것을 목적으로 한다. 부산-거제간 연결도로 건설공사 중 가덕수도의 해저로 횡단하는 침매터널을 건설하기 위해서는 준설작업이 필요하다. 이에 따라 불가피하게 준설선이 가덕수도 항로를 횡단하며 준설을 해야 한다. 이는 상대적으로 가덕수도를 통항하는 선박들의 잠재적인 위험상황으로 충돌 등의 해양사고가 발생할 가능성이 있다. 따라서 이에 대한 선박의 안전통항방안을 모색하고 대책을 제시하였다. 먼저 해상교통량을 추정하고 교통혼잡도를 평가한 결과 장래(2009년)까지 주간 중에 통항량이 최대통항능력에 대비하여 20%미만으로 예상되었다. 그리고 항로설계원칙의 검토를 통해 임시항로를 설정하여 준설공사를 3단계로 나눠 실시하는 대안을 제시하였다. 끝으로 부산신항 VTS 센터의 역할을 강조하였다.