• Journal of Korean Society of Transportation
• /
• v.34 no.6
• /
• pp.535-547
• /
• 2016

This study aims to identify factors that affect the degree of injury severity sustained in traffic crashes on work zone of Korean expressways. To this end, decision tree method was applied to identify influential factors on injury severity and compare characteristics of those factors between work zone and non-work zone. The results from the comparison show that the risk of severity was low when traffic volume and heavy vehicle ratio are high because the factors lower the overall section speed. On the other hand, when the traffic volume and the heavy vehicle ratio are low, the section speed increased and the tendency for high injury severity was confirmed. These findings are expected to help transportation planners and engineers understand which risk factors contribute more to severe injury in the work zones such that they can effectively prepare and implement safety countermeasures.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.7 no.1
• /
• pp.127-136
• /
• 2008

In these days, frequency of constructions on e freeway are increasing according as growing of the importance of e road maintenance and the road management. Work zone on the freeway where vehicles pass with high speed needs control method of lane closure and construction equipment. Because there are seldom researches in domestic study about reflecting characteristics of domestic road, sometimes we have applied for foreign cases to our traffic circumstance but it is not proper to apply for standard of other countries in our cases. foreign nation has different country square, condition of road, and level of people mind. Therefore, this study shows traffic accident characteristics in freeway work zones in Korea. At first, this study collected traffic accident data which include for 3 years $2003{\sim}2005$ in the whole freeway in Korea and then divided the data to five parts - level of the accident, type of the construction work, type of the accident, reason of the accident, according to geometric. According to comparing with non-work zones accident, this study found traffic accident characteristics in freeway work zones in Korea and suggested some alternative ideas for safety of work zones.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.19 no.2
• /
• pp.48-61
• /
• 2020

The objective of this study is to estimate traffic capacity based on the heavy-vehicle ratio in a two-lane freeway work zone where one lane is blocked by construction. For this, closed circuit television (CCTV) video data of the freeway work zone was collected, and the congestion at an upstream point was observed. The traffic volume at a downstream point was analyzed after a bottleneck was created by the blockage due to the upstream congestion. A distribution model was estimated using observed-time headway, and the road capacity was analyzed using a goodness-of-fit test. Through this process, the general capacity and an equation for capacity based on the heavy-vehicle ratio passing through the work zone were presented. Capacity was estimated to be 1,181~1,422 passenger cars per hour per lane (pcphpl) at Yeongdong, and 1,475~1,589pcphpl at Jungbu Naeryuk. As the ratio of heavy vehicles increased, capacity gradually decreased. These findings can contribute to the proper capacity estimation and efficient traffic operation and management for two-lane freeway work zones that block one lane due to a work zone.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.15 no.5
• /
• pp.83-94
• /
• 2016

Providing a voice alarm to drivers approaching a work zone could be an effective alternative to mitigate the potential safety problems of the work zone. This study conceived a voice alarm with a direction sound speaker and a field test was conducted that evaluated the feasibility of the voice alarm at a highway work zone. During the field study, we carried out on-site driver surveys to obtain drivers' perception and preference, collected approaching speeds, and measured sound level during the off-peak 2-hour for two days, respectively. The results showed that while the voice alarm has the potential to be an effective tool in improving safety, the alternative appeared to have the negative effect of noise. Further refinement to a voice alarm with a directional speaker is required to improve feasibility, and the results are expected to be utilized as basic data useful for the refinement.

• International Journal of Highway Engineering
• /
• v.11 no.3
• /
• pp.111-120
• /
• 2009

Recently, pay adjustment regulation (PAR) has been developed to induce better performing road pavements around the country. This regulation was successfully applied during rehabilitation of highway flexible pavements for the first time, and their results are the focus of this paper. For highway pavements, a lot has been defined by typical amount of works a day. This lot was further divided into several sublots depending on field conditions. According to AASHTO Quality Assurance Guide Specification, pay factors for each lot were statistically determined with field measurements of five performance indicators. And composite pay factors were calculated by accounting for the impact of individual performance indicators on a long-term performance of pavement. In 2008, the PAR was tested with asphalt overlays conducted at all six local headquarters of Korea Expressway Corporation. Also, concerns raised during implementation are discussed in this paper. Limited data used in this study showed that if all performance indicators fall within the construction limits with less variances final construction costs may increase by 50%, whereas 10% reduction in construction costs could be necessary if key performance indicators such as density do not meet the construction quality requirements.

• Journal of Korean Society of Transportation
• /
• v.31 no.4
• /
• pp.58-66
• /
• 2013

Due to the characteristics of urban freeways such as heavy traffic and high speed, work zone on urban freeways causes the increase of not only the likelihood of crash occurrence but also traffic congestion caused by lane drop, lane change, acceleration/deceleration, and etc. This paper aims to determine the proper length of transition area that satisfies two criteria, mobility and safety, to make the operation of work zone more efficient. For the analysis, three different scenarios were developed by the number of lanes and the proper length of transition area were determined by changing the length from 100m to 500m in 100m increments. The results showed that the proper length of transition area for 3- and 4-lane freeways is 300m, whereas the proper length of 2-lane freeways is 200m. The results indicated that the different length of transition area based on the number of lanes is more desirable and efficient.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.18 no.3
• /
• pp.46-57
• /
• 2019

Generally speeding appeared to be the most contributing factor of fatalities occurred in work zones, and highway agencies in South Korea have concerned of the safety of workers and drivers in the poor circumstances. In this study, a portable variable message signs (PVMS) system as an alternative of control speeding in work zones was implemented. This study evaluated the safety effectiveness of the PVMS based on speeds and the compliance with the speed limit. Linear regression and logistic regression models were adopted to quantify the safety effect of the PVMS between the 'before' and 'after'. The results showed that most of points had statistically significant speeds reduction experience after PVMS installation. Also, the percentage of vehicle exceeding the speed limit by 10 km/h or more was decreased significantly between 50 and 80% in the 'after' periods compared to the 'before' periods. Therefore, the PVMS would be contributed to benefit safety in work zones which there is a difference in design speed of the adjacent normal section.

• 도로교통
• /
• s.73
• /
• pp.86-97
• /
• 1997

• Journal of Korean Society of Transportation
• /
• v.34 no.4
• /
• pp.354-372
• /
• 2016

This study identified factors affecting the crash severity at freeway work zones. A nice feature of this study was to take into account the characteristics of work zone traffic management in analyzing traffic safety concerns. In addition to crash records, vehicle detection systems (VDS) data and work zone historical data were used for establishing a dataset to be used for statistical analyses based on an ordered probit model. A total of six safety improvement strategies for freeway work zones, including traffic merging method, guidance information provision, speed management, warning information systems, traffic safety facility, and monitoring of effectiveness for countermeasures, were also proposed.

• Proceedings of the KOR-KST Conference
• /
• 1998.10a
• /
• pp.116-125
• /
• 1998

도로공사로 인해 차선의 일부가 폐쇄된 경우에 이용하는 차선에 따라서 운전자의 통행패턴은 달라진다. 공사구간이 없는 경우 운전자의 차선변경은 제한적이나마 각 차선의 밀도에 의해서 좌우되는 것으로 나타났다. 또한 차선폐쇄지점 전방에서는 차선변경할 확률은 폐쇄지점까지의 남은 거리에 따라서 음지수함수를 따르는 것으로 확인되었다. 또한 논문에서 공사구간에서의 차선변경행태와 교통량, 밀도, 속도를 산정하였으며, 공사로 인한 차선별 지체시간을 산정하였다.