PURPOSES : This study was conducted to investigate the stress distribution and resulting effects in the joint between CRCP and JCP when temperature deformation occurs. METHODS : The tie bars, CRCP and JCP pavements, and lean concrete base were created as three-dimensional finite element models using ABAQUS, a general-purpose finite element analysis program. Contact stress analysis was performed between rebar and JCP and between JCP and lean concrete base layer. In the section where stress concentration occurred, the degree of damage was estimated using the CDP model. RESULTS : Since the domestic CRCP does not have a separation layer between the base layer and the surface layer, it was found that when connected to a JCP where the base layer and the surface layer are completely separated, stress concentration occurs around the tie bar at the connection point. Analysis results using the CDP model showed that 25 to 32 mm around the reinforcing bar exceeded the elastic range of concrete. CONCLUSIONS : At the point where CRCP and JCP are connected, local stress concentration is inevitable because the friction and bonding conditions with the base layer and the degree of curling deformation restraint by CRCP rebars are different, and design improvement is expected through life cycle cost and long-term measurement analysis.

PURPOSES : In this study, the initial behaviors of shoulder concrete slabs and tiebars at the longitudinal construction joints between the shoulder JCP and mainline CRCP are investigated. METHODS : The strains of concrete and tiebars were measured at the longitudinal construction joint between the CRCP and JCP. Measurements were performed using data accumulated over a month after concrete placement. The contact conditions were investigated by comparing the strains at each location. RESULTS : The longitudinal construction joints between the shoulder JCP and mainline CRCP exhibited the composite behavior of bonding and friction, and a virtual neutral axis was formed inside the JCP. At the connection of the shoulder concrete, the strain and temperature of the concrete were inversely proportional. The tiebars connecting the CRCP and JCP exhibited different behaviors depending on the bonding conditions around the tiebars of the construction joints. In the presumed state in which the bonding condition was maintained, the concrete temperature and tiebar strain were directly proportional; however, the presumed state of the separation condition exhibited an inversely proportional relationship. In the 24-h behaviors of the tiebars, the effects of the horizontal and curling movements overlapped, and the strains of the measured tiebars increased at the minimum and maximum temperatures of the shoulder JCP. CONCLUSIONS : The strains in the tiebars and concrete slabs primarily depended on the boundary conditions (bonding and friction) of the longitudinal construction joint between the shoulder JCP and mainline CRCP.

PURPOSES : This study prioritizes the potential technology for establishing an efficient traffic control in the ramp junction of urban deep underground tunnels in the future. We considered most of the applicable technologies that ensure traffic safety at the on-off ramp junction. METHODS : This study proposes a methodology to prioritize the applicable technology for establishing efficient traffic control in the ramp junction of an urban deep underground tunnel using an analytical hierarchy process (AHP). First, an AHP structure was developed. Second, an individual survey was conducted to collect the opinions of road and transportation experts. Based on the survey results, weights were estimated depending on the relevant criteria of the developed structure. The estimated weights were verified using the consistency index (CI) and consistency ratio (CR). In addition, a sensitivity analysis was performed to confirm the reliability of the estimated weights. Finally, the potential technology for an efficient traffic control in the ramp junction of an urban deep underground tunnel was prioritized. RESULTS : In the first level of hierarchy, traffic demand control had the highest priority, and ramp metering, section speed control, and shoulder lane control were selected in the second level of hierarchy. CONCLUSIONS : These results implied that prioritizing would be useful in establishing traffic operation strategies for traffic safety when constructing and opening deep underground tunnels in urban areas in the future.

PURPOSES : The purpose of this study is to derive specific road design elements for safe urban underground and to adopt measures for minimizing traffic delays and to maintain efficient operation. METHODS : In this study, a qualitative study was conducted using Focus Group Interview (FGI) method to identify significant connection characteristics and develop connections to urban underground roads. Finally, this study analyzes design elements necessary for traffic safety and efficient traffic operation. In addition, relevant case studies were performed with keywords from the FGI method results. Therefore, major design elements were analyzed for urban underground road connection and connection analysis for traffic simulation-based verification. RESULTS : The main characteristics of the connection between the underground roads of the downtown area were divided into three types: traffic flow characteristics, geometric characteristics, and driver behavioral characteristics. From the review of 16 leading studies (10 domestic papers and 6 international papers) according to the characteristics, the main design factors for “traffic flow characteristics” include the traffic volume, design speed, heavy vehicle ratio, and lane change. The important design elements for “geometric characteristics” include the separation distance, number of lanes, slope, lane and shoulder width and the design factors for “driver behavioral characteristics” showed reaction time, driver vision, and driving speed. CONCLUSIONS : The FGI method identified the main characteristics of connections to the underground roads. In addition, the relevant empirical and theoretical research data were considered in case studies, and the design elements were derived and separated spatially based on the features of each design element, establishing a point-specific design element guideline.

PURPOSES : This paper is to deliver an engineering design guide currently unavailable that highway engineers can refer to when they need to determine the safe distance between the starting point of the underground highway in a metropolitan area and the access points of the adjacent highway. METHODS : The distance between two different highway points should be sufficiently far to support the number of lane changes that drivers may take comfortably at the cruising speed in critical traffic conditions. RESULTS : The proper distance for the selected case study is calculated to be 160 and 200 m at the cruising speeds of 40 km/h and 50 km/h, respectively, without significant increase in potential conflicts estimated by the combination of the VISSIM and SSAM analysis. CONCLUSIONS : The proposed design method can be referred in urban metropolitan areas where no specific design guide is yet available, and it would prevent the unnecessary increase in construction costs and encourage private-public partnership highway businesses.

본 논문에서는 포스트텐션 콘크리트 포장(PTCP: Post-Tensioned Concrete Pavement)과 줄눈 콘크리트 포장(JCP: Jointed Concrete Pavement)이 접속되는 터미널 조인트의 시공시 초기 줄눈 폭 설계에 대하여 연구하였다. PTCP와 JCP 사이의 줄눈 폭은 소음과 승차감에 직접 영향을 미치는 요소이다. 초기 설계 줄눈 폭이 지나치게 크면 소음과 승차감을 저하시키고, 줄눈 폭이 지나치게 작게 되면 온도 상승시 슬래브의 팽창과 블로우업 발생으로 압축응력이 과도하게 작용하여 줄눈부 파손을 야기할 수 있기 때문이다. 본 연구는 온도변화에 따른 터미널조인트의 줄눈 폭의 연구를 위하여 PTCP와 JCP가 시공된 동해고속도로 주문진현장에서 2010년 8월과 11월에 줄눈 폭 데이터를 측정하고 분석하여 최적의 줄눈 폭 설계방안을 제시하였다.

본 연구에서는 콘크리트포장 확장접속부의 추적조사를 통해 시공 및 설계상의 문제점을 확장구간의 평탄성 저하, 진동이 콘크리트에 미치는 영향, 접속부의 접속불량의 관점에서 분석하였다. 기존 측대 일부분만 절단한 경우 접속부에 윤하중이 반복 집중되어 종종 과도한 벌어짐과 단차로 이어지는 것이 목격되었다. 또한 팻칭된 부분에 균열이 재 발생되는 모습도 관찰하였다. 2004년 같은 시기에 신설 준공된 구간과 평탄성을 비교한 결과 확장 준공된 구간의 평탄성 값이 다소 높게 나타났다. 확장구간 설계 시 3차선 4차선으로 확장하는 경우 기존 구간에 설치된 타이바의 내력이 부족해지는 경우에 대해 설명하였다. 현행 타이바를 시공하는 방법에 의한 타이바의 정착강도가 소요강도의 57%에 불과하므로 대안을 제시하였다.

공동구용 수직구 접속부는 부등침하 발생, 지하수위 저감, 지진 등 동하중에 의한 상대변위 발생 등의 문제점이 야기되고 있다. 현재 국내에서는 수직구 접속부 시공 시 지반안정화를 위한 각종 공법을 적용하고 있으나, 접속부에 대해 직접적인 보강/차수 기술 적용은 전무한 실정이다. 따라서 본 연구에서는 공동구용 수직구 접속부에서 야기되고 있는 문제점을 상쇄할 수 있는 공동구용 수직구 접속부 보강/차수 장치 시제품을 개발하였다.

Shield tunnel-shaft joint has caused problems in use which has different soil condition and boundary condition according to structure type. For solving this problems we developed joint reinforcing and inflow water cut-off system which can ensure stability of shield tunnel-shaft and reduce costs of maintenance.

In this study, We could foresee the consolidation settlement at the bridge transition part by APDL(Ansys Parameter Design Language) technique, which is properly applied to the three dynamic interaction analysis. A series of the automatic numerical procedure applied to predict of a plastic settlement by train driving.

In this study, ultrasonic detection device was applied to investigate connection part of concrete structure. Result of test, the internal void of connection part can be detected and it was possible to adopt the ultrasonic detection method to the maintenance of concrete structure.

본 연구는 개선된 한국형 도로용량편람 작성 작업의 일환으로 고속도로 연결로 접속부에 대한 분석방법에 관해 검토한 것으로 1992년에 작성된 우리나라의 도로용량편람(92KHCM)과 최근에 발표된 미국의 도로용량편람(USHCM2000)의 분석방법론을 비교 검토하여 국내에서의 적용가능성을 타진하고 최적의 분석방법을 정립하고자 하였다 이를 위해 본 연구의 대상구간을 설정하고 기존 방법론을 이용하여 현장 관측치와 비교 평가한 후 수집된 자료들을 분석토록 하였다. 자료의 수집 및 분석 결과 접속차로 1개만을 고려한 92KHCM의 경우 평가에 사용된 모형식에 의한 추정치와 실제 관측치가 다소 차이를 보였으나 접속차로 2개를 고려한 2000USHCM 의 경우 계산치와 관측치가 거의 일치함을 알 수 있었다. 이를 통해 2000USHCM에서의 분석방법론이 보다 합리적인 면이 많이 내포되어 있음을 확인 할 수 있었다. 또한 서비스 수준의 판정기준으로 영향권의 밀도가 사용되어 졌으며 이전의 속도에 비해 교통량의 증가에 따른 민감도가 우수함을 알 수 있었다. 본 연구에서의 분석대상 구간은 독립적인 합류부에 국한하였으나 추후 본 연구는 보다 광범위한 자료의 수집을 통해 연속적인 분류 합류 연결로 접속부에 대한 연구로 확대가 되어야 할 것으로 판단된다