• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.15 no.4
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• pp.91-103
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• 2016

The work zone traffic management is of keen interest because the unstable traffic stream in work zones leads to not only less productive traffic operational efficiency but also negative impacts on traffic safety. A promising method to address such issues is variable speed limit systems(VSLS). VSLS is expected to increase in throughput and to enhance safety by diminishing the crash potential. In addition, the usefulness of VSLS has been demonstrated by significant amount of existing literature. The objective of this study is to identify the effectiveness of VSLS based on a meta analysis technique. Throughput and travel speed were used as measures of effectiveness for VSLS in terms of the operational efficiency and safety respectively. Results showed that approximately 16.4% increase in throughput and 16.5% decrease in travel speed were obtainable by VSLS. The outcomes of this study would be useful in developing technologies and polices for better operation of VSLS.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.3
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• pp.1123-1130
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• 2013

This paper aims to estimate work zone base capacity by the number of lanes for urban freeway. To do this, data were collected from the field survey and the database system maintained by traffic control center, and analyzed with four different methods such as the average maximum observation flow rate, headway, regression analysis, and parameter inspection. The work zone base capacity for urban freeway is estimated based on the average maximum observation flow rate and headway method, which are more reliable methods compared to others. The average capacity is 1,650pcphpl when the design speed is 80km/h. The capacity of four lanes one-way work zones was about 1,700pcphpl, while one of 2 lanes one-way work zones was about 1,600pcphpl. The capacity reduction rates for each are 0.15 and 0.2, respectively. The smaller the number of lane is, the more base capacity is reduced. For verification of results, we estimate the capacity by simulation analysis using PARAMICS, and compare with analytical results by a statistical method. This research can be used for efficient and systemic management of work zone in the urban freeway.

• Korean Security Journal
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• no.25
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• pp.147-164
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• 2010

A variety of work zone including road single-sharing construction add surrounding disorder and increase inconvenience of vehicles and pedestrians and furthermore danger of traffic accidents, which sometimes result in human life damages. Traffic delay due to vehicles and users generating in the course of using large-scale multiplex facilities bring about a great economic loss. Now, a lot of regulations and laws related to traffic safety system on construction sites etc. are established, but can not display efficacy desirably. It brings about continuous economic loss due to human life accidents and delay. For the purpose of solving the problems, it is necessary to import systems such as traffic inducement Security (Japan) and traffic controller (CANADA, USA) This article suggest how improve civil safety and reduce Social cost. therefore This thesis aims at analyzing advanced cases of foreign countries, looking into Korean status, and presenting importing ways of traffic inducement Security appropriate to Korea. It is reasonable to grant grade1, grade2, and technical experts to traffic inducement Security who pass regulated educations and examinations. In addition, by reversing regulations and laws, it is necessary only those who have the licenses of traffic induction guarder etc. can establish construction sites and disordered places on roads. Theory educations for education time must include basic educations and expert educations. Basic educations must include understanding regulations and laws and understanding affairs. Expert educations must include traffic control, safety educations, understanding of traffic accidents, operation of traffic control facilities, and traffic accident settlements. Traffic affairs educations must include traffic induction affairs in sites (hand signals, safety material establishment, traffic accident settlements, and urgent treatments).

• Korean Journal of Construction Engineering and Management
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• v.17 no.5
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• pp.120-129
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• 2016

The user cost is an important analysis item which should be considered together with life-cycle of facility, administrator cost and discount rate in LCCA for efficient asset management of SOC facilities. Especially, a significant delay cost occurs often for users in the road field due to a work zone for cleaning and maintenance, and in such case, the administrator should consider the administrator cost as well as the user cost for more rational decision making. However, the user cost has not been considered in most decision making steps until recently and relevant studies also have not been carried out actively. In this study, the methodology to estimate the user cost and delay cost required in the decision making step using the traffic flow model and the direct benefit estimation model in the traffic facility investment evaluation guideline is suggested. And, the traffic flow model was estimated on 4 national highway sections where maintenance was actually carried out in 2014 using VISSIM and, the user cost and the delay cost were estimated based on the suggested methodology. The analysis result showed that the average user cost of $17,569,000KRW/km{\times}day$ occurred on Section A with approximately 30,000 AADT before a work zone occurred, and in case the first lane was blocked for maintenance, the delay cost of $10,193,000KRW/km{\times}day$ (158%) on average occurred additionally. The delay cost of $1,507,000KRW/km{\times}day$ (115%) and $1,985,000KRW/km{\times}day$ (119%) occurred on Sections B and D with approximately 20,000 AADT respectively and the delay cost of $262,000KRW/km{\times}day$ (105%) occurred on Section C with approximately 10,000 AADT. This result of this study was estimated based on the simulation of traffic flow model so that there is a limitation in its actual application. A study ot develop a highly appropriate model using actual observation data and improve the possibility to apply it through the verification using the simulation will be necessary in future.