Incheon Bridge Research Articles

Impacts of Marine Construction on Tidal and Residual Characteristics: An Example from the Incheon Bridge

Impacts of Marine Construction on Tidal and Residual Characteristics: An Example from the Incheon Bridge

대형 국책 프로젝트 성과 달성을 위한 PMC(Project management Consultant) 도입의 필요성에 관한 연구

Recently, global construction companies are turning to PMC, a high value-added business. However, domestic construction engineering companies are still conducting projects focused on detailed design and construction supervision. This study aims to investigate the necessity of introducing PMC by analyzing the cases of completed projects in which PMC was introduced among domestic construction projects. Among the large-scale national projects in Korea, examples of the application of global standard PM include nuclear power plant projects in the 1970s, Gyeongbu High Speed Rail, Incheon International Airport, Incheon Bridge and Yongsan United States Forces Korea Base Relocation Plan (YRP) projects. However, these projects are PMC projects carried out by advanced global companies in Korea. There is an implication in that the necessity of introducing PMC for the successful completion of large-scale national projects was analyzed through the case analysis of these projects.

An Investigation of the Ship Safety Distance for Bridges across Waterways Based on Traffic Distribution

For ship passage safety, a bridge across a waterway is a risk for accidents. However, no standard for the safe distance between a bridge and a ship is available in Korea. The UK MCA considers the 90% confidence interval of traffic distribution as the acceptable passage range, using it for measuring the separation between offshore wind farms. In this study, an optimal ship safety distance is proposed by evaluating traffic distribution at the Incheon and Busan harbor bridges and analyzing the confidence intervals. The results, based on the Z-score, reveal that at the Incheon bridge, all but one ship for 2-way departure were in circulation within the 95% confidence interval range, whereas at the Busan harbor bridge, six ships for arrival and two ships for departure were outside the 95% range. Based on the results of this study, the design of bridges across waterways can incorporate traffic distribution corresponding to each port.

A Study on the Standard of Ship Safety Distance on Bridge Crossing Navigable Waterways based on Traffic Distribution

Currently, there are bridges in the navigational waters where ships pass through from all parts of the world. However, this is a risk factor for ships that pass through the lower part of the bridge. It cause accidents between bridge and ships. In this study, AIS(Automatic Identification System) data were collected for one month at Incheon bridge which is bridge crossing navigable waterways for the purpose of analyzing the safety distance between bridge pier and ships. The marine traffic survey was conducted by ship’s length and type and based on the results, the survey was conducted on the traffic distribution by divided two-way and one-way passing ship. As a result of traffic distribution, The average deviation for the passage centerline was about 0.05 to 0.08 times the main span width and the traffic distribution was analyzed to be the most similar to the lognormal distribution. In this study, the separation distance between bridge piers and ships was analyzed according he confidence intervals, referring to the UK MCA. As a result, the most suitable safety distance according to confidence interval was that the two-way was chosen as 3.4 times of ship’s breadth and the one-way was chosen as 2.8 times of ship’s breadth by maximum ship’s breadth. According to the above results, the distance according to the confidence interval was chosen as the safety distance and the ship safety distance between ship impact protection and ship’s route was 0.18 times route width for two-way traffic and 0.23 times for one-way traffic.

A Comprehensive Probabilistic Model of Traffic Loads based on Weigh-in-Motion Data for Applications to Bridge Structures

In various efforts to assure safety and serviceability of a bridge structure throughout its lifetime, it is essential to accurately estimate the traffic load effects. Although traffic loads involve large uncertainties and can vary significantly with site-specific traffic environments, bridge design codes and maintenance strategies do not utilize a probabilistic model that can reflect the actual environments and uncertainties of the target bridge. Rapid developments of weigh-in-motion (WIM) technologies now make it possible to collect various types of data describing the characteristics of vehicles and traffic patterns. Based on actual WIM data collected in South Korea, this paper develops a comprehensive probabilistic model describing the characteristics of vehicles and traffic flow so that the traffic load effects of a target bridge can be assessed using a Monte Carlo simulation approach. To describe the characteristics of vehicles and traffic flow in the WIM data, several important random variables are first identified. These key random variables are then incorporated into a comprehensive probabilistic model based on fitted probability distributions and theories of transportation engineering. The developed model is successfully verified by comparing the daily maximum total loads estimated using actual WIM data with those estimated using artificial WIM data generated from the model. Furthermore, bridge traffic load effects, e.g., moment and tension, are estimated using the influence lines of an actual cable-stayed bridge in South Korea (the Incheon Bridge) and are compared with those from the live load model of a design code. Finally, a brief parametric study is performed to explore the possibility that a probabilistic model developed by the proposed approach can be used as a generic probabilistic traffic load model capable of estimating the site-specific traffic loads through customizations based on partial measurements and available information regarding the target bridge.

사장교의 최적 초기형상 및 무응력길이 결정을 위한 간략해석법

고정하중을 받는 사장교의 최적 초기형상 결정을 위한 간략해석법을 제시한다. 이 방법은 비선형 유한요소 해석을 수행하지 않고 최적의 초기형상을 구현할 수 있으며, 최소의 휨모멘트를 발생시키는 무응력길이를 제공한다. 초기형상 해석 후 여타의 하중조합 또는 시공단계해석을 수행하기 위해 무응력길이를 변화시키지 않고 Newton-Raphson 반복법을 수행하는 무응력길이법을 이용한다. 수치예제는 제작캠버를 포함한 인천대교 2차원 모델이며, 제시된 해석법과 상용 유한요소해석 프로그램 MIDAS의 초기형상 해석결과를 비교 분석한다. 주로 케이블의 장력과 주부재의 휨모멘트 및 변위를 관찰하였으며, 두 해석결과는 축방향 변위를 제외하고 모든 결과 값이 서로 잘 일치함을 확인할 수 있었다. A simplified analysis method is first proposed in order to determine an optimized initial shape of cable-stayed bridges including all unstrained element lengths without using complicated nonlinear FE analysis. The unstrained-length based FE method is then presented using the unstrained lengths by the simplified analysis. To demonstrate validity and accuracy of the proposed method, Incheon bridge model having the fabrication camber is constructed and initial shaping analysis is performed using the presented method and commercial finite element analysis program, MIDAS. Resultantly it is shown that the initial solutions by the proposed algorithm are well optimized and in good agreement with those by MIDAS except for axial displacements of the main member.

A Study on Safe Vessel Traffic Speeds Based On a Ship Collision Energy Analysis at Incheon Bridge

A Study on Safe Vessel Traffic Speeds Based On a Ship Collision Energy Analysis at Incheon Bridge

A Philosophical Approach to Project Management: Project as a Phenomenon and the Case of Incheon Bridge

Project as an object of project management inevitably conceives a certain end goal to attain, which represents human dreams, hopes, and visions for the future. This paper attempts to offer a philosophical interpretation of project as a phenomenon that is open toward changeable and uncertain time and space that allows creative human intervention from the moment of its conception through its realization. A case study of Incheon Bridge, a national project in Incheon, South Korea, will elucidate how the phenomenal understanding of project can help project management create a sustainable source of future profits.In the first half of the paper, I will articulate a philosophical interpretation of project as a phenomenon. First, project will be conceived and situated within the world of phenomena that originate from the human mind. Secondly, the benefits of interchange between philosophy and project management studies will be shown to extend our understanding of various realms of human life including politics, economics, society, culture, diplomacy, and education. Ultimately, recasting project as a phenomenon will help broaden the conceptual reach of project management as a general process of realizing human dreams.In the second half of the paper, I will substantiate my conceptual argument with a case study of Incheon Bridge, an internationally acclaimed PM case. The success of Incheon Bridge project owes to the mechanism of translating a philosophical understanding of project as a phenomenon into a concrete matrix of numeric, which helped transparently visualize the whole PM process and further transform Incheon Bridge as a sustainable source of future profits.

Estimation of Extreme Wind Speeds in Korean Peninsula using Typhoon Monte Carlo Simulation

국내 서해대교, 인천대교와 같은 장대교량은 대부분 빈번하게 태풍에 의해 영향을 받는 해안에 위치하였으며, 교량의 길이가 긴 만큼 풍하중에 의한 영향이 다른 하중에 비해 상대적으로 크기 때문에 내풍 안정성을 확보하기 위해 정확한 설계풍속을 산정하는 것이 매우 중요하다. 본 연구에서는 태풍의 기후학적 특성 인자로 중심기압깊이, 태풍이동속도, 태풍이동방향, 최단접근거리를 결정하였으며, 태풍의 기후학적 특성들의 확률 분포를 추정하고, 바람장 모형과 중심기압상승 모형을 적용하여 몬테카를로 시뮬레이션을 실시하였다. 분석결과, 대체적으로 제주도와 남해안 지역의 재현기간 풍속이 크게 나오며 고위도로 갈수록 작아지는 특징을 나타냈다. 이와 같은 특징이 나타난 가장 큰 원인은 고위도 분석지점 표본 태풍의 중심기압이 저위도 분석지점 표본 태풍의 중심기압보다 높기 때문으로 판단되며, 또한 우리나라에 해상에서 육지로 이동하면서 쇠퇴기를 겪어 점차 약해지기 때문인 것으로 분석되었다. 또한, 시뮬레이션 결과를 도로교 설계기준 100년 재현기간 풍속(10분 평균, 지상 10m, 지표조도 II)과 비교한 결과, 태풍시뮬레이션의 결과가 낮게 나타났으며, 이러한 점을 볼 때 도로교 설계기준의 기본 풍속이 높게 산정되어 있다고 판단되며, 기상자료 분석과 같은 추가적인 연구를 통해 기본풍속 조정에 대한 연구가 수행 되어야 할 것으로 사료된다. The long-span bridges such as Incheon Bridge and Seohae Grand Bridge are located on the coastal region effected frequently by strong wind of typhoons. In order to ensure the wind-resistant performance of the structure, estimation of the proper design wind speed is very important. In this study, stochastic estimation of design wind speed incurred by typhoons is carried out. For this purpose, we first established probability distribution of climatological parameters such as central pressure depth, distance of closest approach, translation speed and heading to build statistical model of typhoons, which are employed in Monte Carlo simulation for hypothetical typhoons. Once a typhoon is generated with statistically justified parameters, wind speeds are estimated along its path using wind field model. Thousands of typhoons are generated and their peak wind speeds are utilized to establish the extreme wind speeds for different return period. The results are compared with design basic wind speeds in Korean Highway Bridge Design Code, showing that the present results agree well with similar studies while the existing code suggests higher design wind speed.

Numerical Simulation for Reducing the Flood Damage of Green Park Using MIKE URBAN

In this study, to resolve flood damage in flood-prone areas around Incheon Bridge landfill, numerical analysis was performed according to change of coefficient of runoff considering underground rainfall storage in surrounding parks and facilities to reduce non-point source pollutants. Use of rainfall retention facility to improve urban flooding reduced peak flow and effectively prevented flooding in the subject areas. In the result according to change of coefficient of runoff considering facilities to reduce non-point source pollutants, control of initial rainfall led to reduce peak water level and secure delay time. Based on the study result, to properly install underground retention storage and apply coefficient of runoff according to facilities to reduce non-point source pollutants within the subject areas, providing accuracy of various parameters necessary for future analysis and measurement data will help design effective multi-functional parks with minimized flood damage and prepare measures to prevent disaster.

Ship Collision Risk Assessment and Sensitivity Analysis for Sea-crossing Bridges

본해상교량 프로젝트의 설계단계에서 선박충돌 문제는 주로 교량 하부구조의 단면 결정에 관여하게 되며, 위험도 평가와 충돌 시뮬레이션 등을 통해 설계를 수행하게 된다. 선박의 충돌위험은 다양한 확률모델에 의해 평가되며 대체로 AASHTO Guide(2009)의 Method II와 유사하다. 그러나 해당기준에서 사용되는 일부 요소는 내륙수로에 국한되어 있거나 지역적인 요인이 강하여 설계자의 판단이 요구되므로 관련 기준이나 연구결과 등을 참고하여 결정해야 한다. 본 연구에서는 2010년 선박운항데이터를 사용하여 인천대교에 대한 위험도평가를 수행하고 기존 하부구조 및 방호구조물에 대한 위험도 및 내충돌 성능을 검토하였다. 그리고 AASHTO Guide의 Method II를 기준으로 하여 위험도평가에 필요한 요소들의 추정 방법과 적용 사례, 관련 연구결과에 대한 고찰을 수행하였다. 이로부터 위험도평가에 필요한 요소들의 적절한 가변영역을 정의하고 해당 구간에 대한 민감도 분석을 수행하였으며 설계단계에서 설계자가 주의하여 적용해야 하거나 지역적인 데이터의 직접 분석이 필요한 요소들이 확인되었다. 이번 연구는 해상교량에 대한 선박충돌을 고려한 설계시 위험도 분석과 관련하여 기본적인 참고자료가 될 것으로 판단된다. In the design phase of sea-crossing bridge projects, ship collision problem is mostly participated in decision of substructure section and it would be performed by risk assessment and impact simulations. Ship collision risk is assessed by probability model which is similar to method II of Guide Specification and Commentary for Vessel Collision Design of Highway Bridge(AASHTO, 2009). However, several factors used in the applicable code are limited to inland waterways or have many local characteristics. Accordingly, it should be needed judgement of engineer or referred to related criteria, research finding. In this study risk assessment for In-cheon bridge and review of existing substructure's impact risk and resistance capacity are performed using the 2010's ship passage data. And then consideration regarding to presumption and applied instance of factors needed for risk assessment and related research findings are performed on the basis of AASHTO Guide's Method. As a result of study, adequate variable region of factors needed for risk assessment is defined and sensitivity analysis for appropriate region is performed. Consequently, factors that should be applied carefully or needed for direct analysis of local data are confirmed. This research could be fundamental material to risk assessment related to design for sea-crossing bridge taken into account ship collision.

An Evaluation of a Mass-Casualty Incident which Developed after a Bus Fell Off the Incheon Bridge

An Evaluation of a Mass-Casualty Incident which Developed after a Bus Fell Off the Incheon Bridge

서해안 미고결 지층의 퇴적이력 및 퇴적환경

The west seacoast has approximately 83% of tidal flat in Korea. Gyeonggi-do and Inchon has 35.1%. This study was carried out to understand depositional environment and properties of tidal deposits that distributed in the Gyeonggi bay. On the basis of observation and description on mineralogical, geochemical, physical properties, detailed sedimentary unit has been respectively distinguished Based on. stratigraphic position, facies and unconformity, the intertidal zones are classified into four sedimentary units, and bedrock over the units has been developed in the order of Unit 4Unit 3Unit 2Unit 1. The intertidal sediment deposits of Gyeonggi Bay were compared with those of west coast. In Cheongra area all strata of Unit 4-Unit 3-Unit 2-Unit 1 appear. In Yeongjong-do Unit 2-Unit 1, in Incheon Bridge and Songdo area Unit 4-Unit 3-Unit 1 are observed. In Daesan area Unit 4-Unit 3-Unit 1 are observed. Average clay mineral content ratio is 8.2% in Cheongra area, 2.9% in Yeongjong Island, 18.4% in Incheon Bridge, 24.6% in Songdo area.

콘크리트 주탑의 시간 의존적 거동을 고려한 인천대교의 비선형 해석

최근의 토목분야의 프로젝트에 있어 장대교량의 건설이 주를 이루고 있으며, 장대교량의 여러 형식 가운데서도 사장교가 현재 계획, 설계 중인 프로젝트에서 상당한 비중을 차지하고 있다. 사장교가 대형화 및 장경간화 됨에 따라, 구조물의 경량화를 위하여 강재를 사용한 사장교가 건설되어 왔다. 그러나 많은 사례에서 주탑은 구조적, 경제적인 이유로 콘크리트로 시공되고 있다. 콘크리트는 재료적 특성상 크리프와 건조수축에 의한 장기거동의 영향을 크게 받는데, 이러한 특성으로 인하여 응력의 재분배와 시공 중 구조계의 변화 등 해석상 고려해야 할 부분이 많아진다. 본 연구에서는 철근콘크리트의 비선형성을 고려한 유한요소해석 프로그램 RCAHEST를 사용하여 콘크리트 주탑을 채택한 사장교 중에 국내 최장의 강사장교인 인천대교를 선택하여 해석을 수행하였다. 실제 시공된 교량의 시공단계해석과 완공 후 시간해석을 통하여 콘크리트 주탑만의 시간 의존적 효과가 사장교 전체계에 미치는 영향을 파악하였다. Recently, building of long span bridge is increasing and cable stayed bridges have large portion in civil projects. As the spans of bridges become longer, steel cable-stayed bridges have been constructed mainly for slim structure. But in many case, pylons are constructed by concrete for the stability of structures and the economy. Concrete is greatly influenced by the long-term behavior like creep and drying shrinkage, so analysis of stress redistribution and structural change in construction is required. In this study, as a cable stayed bridge with concrete pylon, Incheon Bridge is analyzed by nonlinear FEM analysis program RCAHEST. Through this analysis, time dependent effect of concrete pylon to whole cable stayed bridge system is studied.

Construction and Geometry Control of Incheon Cable-Stayed Bridge

The Incheon Bridge is a continuous span steel deck cable-stayed bridge with six traffic lanes in dual direction. Its total length is 1480 m including an 800 m centre span. The pylon was designed as an inverted Y-shaped concrete structure of 238 m in height. The pylon consists of four parts, namely the lower part, cross beam, middle part and upper cable anchorage part. The pylon was constructed by being divided into 57 lots of 4 m height, and auto-climbing form was applied. The cross beam was prefabricated at the factory to save construction time and was erected by using a floating crane. In order to control the geometry and secure the stability during construction, temporary tie and struts were installed and tensioned. For the superstructure erection, the side span was fabricated as four large blocks, which weighed 27 000 kN at the factory and was erected on temporary bents by using a 30 000 kN floating crane. The centre span was fabricated as a 15 m long block weighing 3000 kN and erected by a derrick crane along with the stay cables. A total of 208 cables were installed in a semi-fan shaped arrangement and four cables were stressed simultaneously. An integrated geometry control system was developed and applied for geometry control and cable adjustment during the erection. Four systems, namely, data integrated management system, structural analysis system, error adjustment system and measurement system, were employed. Approximately 6 to 7 days of cycle time was achieved for the superstructure erection within the allowable limits of geometry and cable tension. This paper presents the construction and geometry control system applied in the Incheon cable-stayed bridge.

MAXIMIZATION OF SOCIAL WELFARE CONSIDERED TOLL AND TAX (Incheon International Airport Expressway VS Incheon Bridge)

Based on case study of the Incheon International Airport Expressway that is the first private capital road in South Korea and the Incheon Bridge that will be open for traffic in 2010, we knew the maximization of social welfare considered toll and tax on a point of view social surplus. And considered the strategy situation that Incheon International Airport Expressway and the Incheon Bridge should be calculated the expecting response of competitor under the alternative (choose the toll or tax) is not yet determined each other, what is the best alternative plan, how much the quantity of each social surplus, and what strategy will be maximize social welfare appling the game theory based on Nash Equilibrium.