• International Journal of Highway Engineering
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• v.16 no.4
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• pp.51-62
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• 2014

PURPOSES: This research is a basic study for application method in korea of energy harvesting technology, and it is a research to find out the direction of architectural planning through analyzing cases of interseasonal heat transfer system applied buildings. METHODS : In this paper authors investigate application necessity of energy harvesting technology, we analyzed energy use status of building section through analyzing domestic energy consumption status and analyzed domestic renewable energy generation potential. Also we study the features of energy harvesting technology, interseasonal heat transfer system, and case study on interseasonal heat transfer system applied buildings. RESULTS : On the basis of case study on interseasonal heat transfer system applied buildings, we analyzed feasibility study and classified into four sections(economic, environment, design, applicability), and suggested directions of architectural planning. CONCLUSIONS: Economic renewable energy for public and commercial buildings(hospitals, offices, schools, factories) can be provided effectively using Interseasonal Heat Transfer.

• International Journal of Highway Engineering
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• v.15 no.2
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• pp.47-55
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• 2013

PURPOSES : This study aimed to evaluate the feasibility of AASHTO86 design method for Bonded Concrete Overlay. METHODS : The Feasibility of AASHTO86 design method for Bonded Concrete Overlay is investigated based on the following study : i) Sensitivity analysis of designed service life of Bonded Concrete Overlay by major design input for AASHTO86 guide. ii) Comparison of actual Bonded Concrete Overlay life and predicted Bonded Concrete Overlay life by AASHTO86. iii) Finding the stress component influence the potential distress of Bonded Concrete Overlay based on 3-d FEM analysis. iv) Exploring the limitation of AASHTO86 in the aspect of design input. RESULTS : Sensitivity analysis showed that the condition of existing pavement significantly on the Bonded Concrete Overlay life. Also the overlay thickness affect the Bonded Concrete Overlay life. The comparison of actual Bonded Concrete Overlay life and predicted Bonded Concrete Overlay life showed relatively good agreement when the early distress sections are excluded in comparison. Bonding stress occurred at the interface may be larger than the bond strength used in the specification of Bonded Concrete Overlay construction. CONCLUSIONS : Bonded Concrete Overlay life predicted by the AASHTO86 may not be reliable. Number of points to improve the reliability in the design of Bonded Concrete Overlay are suggested in this study.

• Proceedings of the Korea Multimedia Society Conference
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• 2003.11a
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• pp.342-345
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• 2003

자동운전과 안전운전 구현을 위한 첨단 차량 및 도로 시스템(AVHS : Advanced Vehicle & Highway Systems)의 한 분야인 충돌 방지 시스템을 완성하기 위해서는 차량간의 상대 거리, 차량의 속도, 차선의 굴곡 정도, 경사도등을 사용해서 종합적으로 상황 판단을 내려야 한다. 본 논문에서는 이들 요소들중에서 차선의 굴곡도 판단을 근사 추론을 이용하여 실험하였다. 근사추론을 이용한 것은 차선의 굴곡도를 계산형으로 파악할 때의 단점인 계산 시간 오버헤드(overhead), 또 그에 따른 실시간 처리의 어려움, 고가의 장비필요성 등을 극복하기 위해서이며, 실험은 Fuzzy Logical Inference 기법을 사용하였다. 본 연구에서는 실제 도로상에서의 계산된 굴곡도와 실험된 시스템 결과와의 유사성과 그 시스템의 사용 가용성(feasibility)을 검정하였다.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.04a
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• pp.449-454
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• 1999

Pavement concrete subjected to severe environmental condition may be vulnerable to frost attack practically where de-icing chemicals are used. This study focused on the investigation of durability characteristics of pavement concrete incorporation polypropylene fibers and application feasibility of these into the pavements of local roads and highway. A series of labortory tests were performed with main experimental variable such as fiber types, fiber contents. and type of concrete mix. The test of compressive strength was executed as primary tests, before the durability tests such as a scaling resistance were performed. De-icing salt resistance test was progressed by recycling freeze and thaw in the presence of a 4% calcium chloride solution. The deteriorated surfaces were rated by visual inspection and the loss weight were measured at every 5 cycles.

• Computers and Concrete
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• v.1 no.3
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• pp.355-369
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• 2004

This paper presents a study of four finite element techniques that can be used to model slabon-beam highway bridges. The feasibility and correctness of each modeling technique are examined by applying them to a prestressed concrete I-beam bridge and a prestressed concrete box-beam bridge. Other issues related to bridge modeling such as torsional constant, support conditions, and quality control check are studied in detail and discussed in the paper. It is found that, under truck loading, the bending stress distribution in a beam section depends on the modeling technique being utilized. It is observed that the behavior of the bridge superstructure can be better represented when accounting for composite behavior between the supporting beams and slab.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2005.03a
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• pp.380-387
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• 2005

Little has been understood about the seismic behavior of curved bridges due to the different structural characteristics compared to straight bridges. In this study, a simple numerical model, widely used for seismic analysis, is modified for a more realistic estimation of the seismic behavior. The seismic response of curved bridges obtained with the modified simple numerical model was compared with the result using a more sophisticated model to verify the feasibility. Seismic analyses were performed on three-span continuous curved bridges, which is a structural system widely used in highway structures. Numerical model of the three-span continuous curved bridges were subjected to seismic loads in diverse directions. From the result of the analysis. it was found that the direction of the seismic load have significant effect of the seismic behavior of curved bridges when the central angle exceeds 90 degrees.

• International Journal of Highway Engineering
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• v.16 no.4
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• pp.97-110
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• 2014

PURPOSES: This study is to find the substantial shortcomings embedded in the government policies and practical administrative processes associated with the Korean Transportation Database (KTDB) and to propose preliminary approaches to overcome. METHODS: Administrative and socioeconomic issues on inefficiency in public and private investment and redemption was found from the literature review. Through the interview of sets of experts and practitioners, a set of faultiness embodied in the administrative procedure utilizing and managing KTDB was found and analyzed. RESULTS: This study found the erroneous administrative elements categorized into four groups: faulty socioeconomic data supporting local governors's optimistic will yielded overestimation of future traffic demand; faulty data incidentally introduced in KTDB burdened traffic demand analysis; unavoidable misuse of KTDB worsened the unstability of KTDB; and apathy to manage the KTDB data deviated systematic management. The proposed includes the alteration of the administrative and technical systems to overcome those shortcomings. CONCLUSIONS : Erroneous administrative elements associated with KTDB should be concerned prior to indicating subsequential faultiness in demand analysis.

• International Journal of Highway Engineering
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• v.8 no.3 s.29
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• pp.155-162
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• 2006

Deflections of jointed concrete pavements at test road are monitored during 48 hours. And methods of calibration with respect to curling deflections are suggested. Relations between deflection ratio of center to joint at test time and deflection ratio of center at test time to center at reference time are described by regression. From deflections at test time, deflections transformed to reference time which gives minimum deflections in a day are estimated through regression curves and concluded to propose as a alternative method of curling calibration with more data accumulation.

• International Journal of Highway Engineering
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• v.15 no.2
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• pp.57-63
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• 2013

PURPOSES : This study was performed to investigate a feasibility of job-site use of recycled concrete aggregate exceeding 3% of absorption rate. Test variables are coarse aggregate types such as natural aggregate, job-site processed recycled aggregate, and recycled aggregate processed from the intermediate waste treatment company. METHODS : First, aggregate properties such as gradation, specific gravity and absorption rate were determined. Next a basic series of mechanical properties of concrete was tested. RESULTS : All strength test results such as compression, flexure and modulus were satisfied for the minimum requirements. Finally up to first 48 elapsed days the shrinkage strains of concretes made from both recycled aggregates (in case of volume-surface ratio of 300) appeared to be greater than 26% of the companion concretes made from natural aggregates. CONCLUSIONS : Drying shrinkage result is ascribed to greater absorption rate and specific gravity of those specimens made from recycled aggregate. This may be reduced with an addition of admixtures.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2007.04a
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• pp.39-42
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• 2007

It is necessary to estimate the dynamic characteristics of stay cables ie., the natural frequencies and the damping ratios of the stay cables to design cable damper for appropriate mitigation of cable vibrations and/or to estimate the tension of cables in service. In this study, a cable exciting robot for evaluating dynamic characteristics of stay cables has been developed, and the feasibility of the developed system has been demonstrated through a field test on the stay cable installed at the test yard of Highway and Transportation Technology Institute (HTTI). The dynamic characteristics of the stay cable were estimated based on acceleration data as well as displacement measured by digital image processing technique.