• 국제학술발표논문집
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• The 3th International Conference on Construction Engineering and Project Management
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• pp.914-919
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• 2009

The research investigates for the relationship between the operating performances of the make-ready process and project production performance. To this end, the researchers proposed a metric of PCR (Percentage of Constraint Removal) to measure the make-ready performance. The study measured the production performance in two ways: production planning reliability and progress performance. We hypothesized that how well the make-ready process is performed has an impact on the degree of production performance. The statistical analyses are used to investigate that how operating performance of the make-ready process affects project production performance. The results of the regression analysis support our hypotheses (p<0.25) and correlation coefficients for the relationship between project production performance and make-ready performance are also significant (p<0.05).

• 국제학술발표논문집
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• The 6th International Conference on Construction Engineering and Project Management
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• pp.371-375
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• 2015

Design-Build (DB) has gained in popularity in roadway projects due to its defining advantage to improve communication and fast-track project delivery. However, very little is known about the impact of change order frequency and occurrence timing pertaining to DB projects. The study analyzes their impacts on project time and cost performance by conducting a rigorous numerical analysis drawing on 530 3R (rehabilitation, reconstruction, and resurfacing) projects completed between 2002 and 2011 in Florida by using a multiple linear regression. The results indicate that DB outperformed Design-Bid-Build in project cost as well as time. Critically, the regression analysis signifies that earlier change order occurrence caused more unfavorable impacts on schedule and cost. The proposed analyses and models will lead to the improved ability of agencies to quickly and more reliably estimate the potential change order impacts on schedule and cost.

• 한국건설관리학회논문집
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• 제10권1호
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• pp.78-90
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• 2009

오늘날 고속도로 운영은 IT를 기반으로 하는 복잡한 Digital Infrastructure이다. 이러한 IT의 활용은 점점 많아지고 있는데, 예측 불가능한 운영위험이 발생할 경우 IT의 편리함만큼이나 피해가 예상외로 커질 수 있다. 고속도로 운영 위험은 도로의 운영이 중단되어 도로이용자들이 서비스를 제공받지 못하는 것이다. 운영위험은 예상하지 못한 과다한 운영관리비 및 유지관리비의 발생으로 계획된 운영비를 초과하는 것이며, 운영수입의 손실을 가져온다. 그 결과 이용자 안전의 위험과 운영자의 부실을 초래하게 되는데, 기존의 연구는 이를 추정할 수 있는 방법에 대한 연구가 미흡한 실정이다. 따라서 본 연구에서는 디지털화된 고속도로에서 대규모 정전사태가 발생할 경우 추가로 발생되는 운영비 항목을 구체적으로 제시하고 각 항목에 대한 예상 가능한 위험비용을 시뮬레이션 추정을 하고자 하였다. 이를 근거로 하여 운영위험을 방지하기 위한 비용예산과 운영계획 측면에서 방안을 제시하고자 하며, 향후 운영의 건전성을 확보할 수 있는 기초자료로 활용을 도모코자 한다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 추계 학술발표회
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• pp.49-59
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• 2010

Earthquake-induced liquefaction on saturated loose sand is well known in the world. Since Saemangeum Dike Project has a plan to be reclaimed with dredged sand on wide river, possibility of liquefaction should be checked. Section Dongjin5 was selected to evaluate possibility of liquefaction. Estimating method follows as 1) determination of PL value with SPT results, passing curve, and soil properties, 2) prediction for maximum earthquake acceleration, 3) calculation for FL value on depth with Korean specification for highway bridges, 4) visualization for possibility of liquefaction on all of project area with GIS 5) comparison with Japanese specification for highway bridges, Youd and Idriss method, and Andrus and Stokoe II method for verification, 6) ascertainment for the potential liquefaction with cyclic triaxial test. 7) establishing for countermeasure if needed. From the results, even though most of area covered with sand, no potential liquefaction exists except some areas. Those need to soil improvement with grout or attaching measurement on substructure.

• 국제학술발표논문집
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• The 5th International Conference on Construction Engineering and Project Management
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• pp.576-582
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• 2013

Typical highway infrastructure systems include roadway pavement, drainage systems, tunneling, and other hardware components such as guardrails, traffic signs, and lighting. Tunnels in a highway system have provided significant advantages to overcoming various natural challenges including crossing underneath bodies of water or through mountainous areas. While only a few tunnel failure cases have been reported, the failure rate is likely to increase as these assets age and because agencies have not emphasized tunneling asset management. A tunnel system undergoes a deterioration life cycle pattern that is similar to other infrastructure systems. There are very few agencies in the United States implementing comprehensive tunnel asset management programs. While current tunnel asset management programs focus on inspection, maintenance, and operation safety, there is an increasing need for the development of a comprehensive life cycle tunnel asset management program. This paper describes a conceptual framework for a comprehensive tunnel asset management program. The framework consists of three basic phases including a strategic plan, a tactical plan, and an operational plan to provide better information to the decision makers. The strategic plan is a basic long term approach of tunnel asset management. The tactical plan determines specific objectives and the operational plan actually applies asset management objectives in practice. The information includes operational condition, structural condition, efficiency of the system, emergency response, and life cycle cost analysis for tunnel capital improvement project planning.

• 기술사
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• 제34권1호
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• pp.23-26
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• 2001

Seohae Grand Bridge is a part of the new West Coast Highway(353km) under construction, which connects Inchon and Mokpo. It is the longest bridge in Korea (7.31 km), and has 97 spans of 60m each precast segmental approach bridges, 2 main spans of 165m each free cantilever segmental bridge(500m), and 1 stay cable bridge of 990m In total length. During the seven year long construction period, many new construction technologies and methods were utilized for the first time in Korea, and gave invaluable opportunities to experience and master these in completing the project on time with safety and precision. I am proud of being a member of this project, and wish to express deep appreciations to those who participated in the project.

• Journal of Construction Engineering and Project Management
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• 제7권1호
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• pp.30-36
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• 2017

Most local agencies such as counties and small cities continuously express difficulties in making technically and financially defensible decisions on their pavement infrastructure maintenance and rehabilitation. Unlike pavement systems managed by state highway agencies, the total lane-miles of many local pavements are significantly short and they are managed by a limited number of staff who typically have multiple responsibilities. Most local agencies also do not have historical pavement performance data and the lack of a systematic decision making framework exacerbates the problem. A structured framework and an easily accessible decision support tool that reflects their local requirements, practices and operational conditions would greatly assist them in making consistent and defensible decisions. This study fills this gap by developing a systematic pavement treatment selection framework and a spreadsheet based tool for local agencies. It is expected that the proposed framework will significantly help local agencies to improve their pavement asset management practices at the project level.

• 국제학술발표논문집
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• The 2th International Conference on Construction Engineering and Project Management
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• pp.820-829
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• 2007

This paper presents an evaluation of feasibility studies conducted to justify investments in infrastructure projects. An analysis of a previous feasibility study for a highway construction project is presented in this paper with an emphasis on the estimates and forecasts presented in that study in order to weigh expected benefits from the project against expected costs. The forecasted numbers are compared with actual data collected during the operation phase about the usage of the facility. The comparison reveals a huge difference between estimated numbers and actual numbers. Based on the lessons learned from the analyzed case study, recommendations are presented to improve feasibility studies for infrastructure projects including: peer review of feasibility studies; before-and-after feasibility studies; and defined scope and methodology for feasibility studies. Decision makers are advised to take outcomes of feasibility studies for infrastructure projects with extreme caution as some studies may provide erroneous and misleading input to their decisions regarding investment in infrastructure projects.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2006년도 정기 학술대회 논문집
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• pp.922-927
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• 2006

There is a concern with worldwide deterioration of highway bridges, particularly reinforced concrete. The advantages of fibre reinforced plastic(FRP) composites over conventional materials motivate their use in highway bridges for replacement of structures. Recently, an FRP deck has been installed on a state highway, located in New York State, as an experimental project. In this paper, a systematic approach for analysis of this FRP deck bridge is presented. Multi-step linear numerical analyses have been performed using the finite element method to study the structural behavior and the possible failure mechanism of the FRP deck-superstructure system Deck's self-weight and ply orientations at the interface between steel girders and FRP deck are considered in this study. From this research, the results of the numerical analyses were corroborated with field test results. Analytical results reveal several potential failure mechanism for the FRP deck and truss bridge system The results presented in this study may be used to propose engineering design guideline for new and replacement FRP bridge deck structure.

• Geomechanics and Engineering
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• 제21권6호
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• pp.565-570
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• 2020

Large tonnage pile foundation load test system is designed in this paper by using pre-stressed technique to optimize the design of anchor pile reaction beam system, in which project pile can be successfully taken as anchor pile. The test results show that the cracks and excessive deformations of the prestressed anti-force device designed in this study have not occurred, and the prestressed tendons of the anchor pile ensure that the anchor pile will not be pulled and fractured, and the prestressed tendons can be reused, thus ensuring the safety and reliability of the test. This test method can directly test bearing capacity of long rock-socketed piles, and analysis bearing behaviors from test results of sensors which embedded in the pile. Through test studied, authors summarized the vertical bearing characteristics of long rock-socketed piles and the main problems that should be paid attention to during design and construction, and provided reliable solutions.