차선테이프의 재료별 성능평가를 통한 현장적용 연구

안덕순 한국도로학회 2021 한국도로학회논문집 Vol.23 No.6

PURPOSES : The purpose of this study is to preliminarily examine the field applicability of modular pavement marking tape (PMT) to increase the lane awareness of motorists on existing roadways. METHODS : A pavement marking tape (PMT) comprises an adhesion layer and a paint coating layer. The adhesion layer is prepared using gussasphalt-based materials that have properties similar to those of existing asphalt materials. Thermal adhesion is performed to adhere the tape to the pavement. For the paint coating layer, polyurea materials are selected after reviewing the existing materials suitable for pavement lane marking. To conduct field evaluations on the adhesion layer, monitoring is performed after the pilot deployment of the PMT is completed. Twelve samples are prepared to investigate the optimal ratios for the mixture of paint coating layer materials. The durability of the PMT is examined using a turntable road-marking test system (RPA) with a wheel load on the samples. A total of 50,000 RPA, equivalent to P4, is performed. The performance is evaluated by capturing the retroreflectivity measure, which is used as an indicator of the pavement marking performance. The PMT is utilized on a roadway segment with significant heavy vehicle traffic, and continuous monitoring is performed to examine its performance in the field. RESULTS : Based on a visual inspection of the adhesion layer material, no significant issue is observed in terms of the adhesion performance of the PMT. Furthermore, the overall retroreflectivity obtained from the RPA exceeds 300 mcd/m2·lux. It is discovered that the optimal ratios for the mixture of polyurea and binder for the paint coating layer are 4:6 and 2:8, respectively, which results in a retroreflectivity that is 90% or above the initial retroreflectivity. Using a prototype of the PMT for field tests, a performance evaluation is conducted by analyzing the retroreflectivity measured after 2 and 7 weeks from the prototype deployment. The retroreflectivity measured for the first 2 weeks after the deployment appears acceptable for field use. However, the retroreflectivity is reduced significantly when it is measured 7 weeks after deployment, resulting in the necessity for a more reliable material that can retain long-term durability. CONCLUSIONS : The lane awareness of a motorist is crucial for accident mitigation under not only nighttime driving, but also severe weather conditions. In this regard, modular PMT is expected to increase the lane awareness of motorists, thereby improving the quality of lane marking materials. In this study, various exploratory field tests are conducted to analyze the field applicability of the PMT. It is noteworthy that the results presented herein are obtained from preliminary performance evaluations of the PMT. Hence, further investigations pertaining to the long-term durability of PMTs must be conducted using advanced test equipment such as an accelerated pavement tester.

차선테이프의 재료별 성능평가를 통한 현장적용 연구

안덕순 한국도로학회 2021 도로 : 도로학회지 Vol.23 No.3

PURPOSES : The purpose of this study is to preliminarily examine the field applicability of modular pavement marking tape (PMT) to increase the lane awareness of motorists on existing roadways. METHODS : A pavement marking tape (PMT) comprises an adhesion layer and a paint coating layer. The adhesion layer is prepared using gussasphalt-based materials that have properties similar to those of existing asphalt materials. Thermal adhesion is performed to adhere the tape to the pavement. For the paint coating layer, polyurea materials are selected after reviewing the existing materials suitable for pavement lane marking. To conduct field evaluations on the adhesion layer, monitoring is performed after the pilot deployment of the PMT is completed. Twelve samples are prepared to investigate the optimal ratios for the mixture of paint coating layer materials. The durability of the PMT is examined using a turntable road-marking test system (RPA) with a wheel load on the samples. A total of 50,000 RPA, equivalent to P4, is performed. The performance is evaluated by capturing the retroreflectivity measure, which is used as an indicator of the pavement marking performance. The PMT is utilized on a roadway segment with significant heavy vehicle traffic, and continuous monitoring is performed to examine its performance in the field. RESULTS : Based on a visual inspection of the adhesion layer material, no significant issue is observed in terms of the adhesion performance of the PMT. Furthermore, the overall retroreflectivity obtained from the RPA exceeds 300 mcd/m2·lux. It is discovered that the optimal ratios for the mixture of polyurea and binder for the paint coating layer are 4:6 and 2:8, respectively, which results in a retroreflectivity that is 90% or above the initial retroreflectivity. Using a prototype of the PMT for field tests, a performance evaluation is conducted by analyzing the retroreflectivity measured after 2 and 7 weeks from the prototype deployment. The retroreflectivity measured for the first 2 weeks after the deployment appears acceptable for field use. However, the retroreflectivity is reduced significantly when it is measured 7 weeks after deployment, resulting in the necessity for a more reliable material that can retain long-term durability. CONCLUSIONS : The lane awareness of a motorist is crucial for accident mitigation under not only nighttime driving, but also severe weather conditions. In this regard, modular PMT is expected to increase the lane awareness of motorists, thereby improving the quality of lane marking materials. In this study, various exploratory field tests are conducted to analyze the field applicability of the PMT. It is noteworthy that the results presented herein are obtained from preliminary performance evaluations of the PMT. Hence, further investigations pertaining to the long-term durability of PMTs must be conducted using advanced test equipment such as an accelerated pavement tester.

The Effects of Pavement Markings on High-risk Drivers’Speeds

이종학,노관섭,김종민,최재성 한국도로학회 2013 한국도로학회논문집 Vol.15 No.1

PURPOSES : Speeding is often the primary contributor to fatal crashes. Surprisingly, driving behaviors are indirectly affected by personal factors such as law-abidance, risk sensitivity, and situational adaptability. This research aims to verify the effectiveness of pavement markings at reducing the speeds of high-risk drivers. The purpose of this study is to establish how drivers (including law-abiding or law-breaking, high-risk or low-risk) react to different pavement markings in a driving simulator. METHODS : The five different pavement markings were selected from markings used in other nations. The forty-two drivers were then surveyed, via questionnaires, and placed into the corresponding groups. Finally, statistical analysis was conducted to determine the extent of speed reduction for each pavement marking. RESULTS : Higher speeds were linked to the high-risk drivers. Furthermore, after analysis of the mean difference of average speeds by pavement marking, it was determined that Dragon’s Teeth had the greatest speed reducing effect on these drivers. CONCLUSIONS : Perceptual countermeasures are unlikely to strongly affect high-risk drivers’ perception of speed on the curves. This statistically demonstrates that Dragon’s Teeth have a subtle effect on reducing speeds in the driving simulator. This study’s significance lies in the improved understanding of high-risk drivers in terms of road facilities. It approaches the effects of various patterns of pavement markings for high-risk drivers.

휘도 대비를 이용한 악천후 도로 노면표시 시인성능 평가

이석기,박원일,박기수,김용석 한국산학기술학회 2023 한국산학기술학회논문지 Vol.24 No.11

Visibility of pavement markings is directly related to the contrast between the luminance of markings and that of pavement. However, the current national standard uses the retro-reflective coefficient as a visibility index, but this index only covers the visibility of the markings, not the pavement. This study proposes using the luminance contrast as a visibility index. The luminance contrast corresponding to adverse weather conditions was quantitatively evaluated. The study results were a luminance contrast ratio of 8.02 in normal weather, 0.70 in foggy weather, 0.60 in rainy weather, and 0.71 in wetness after rain. The luminance of markings was 3.82 in normal weather, 1.98 in foggy weather, 3.67 in rainy weather, and 2.07 in wetness after rain. Luminance of a marking in rainy and wet conditions was lower than that of the background pavement, so it is almost impossible to achieve the functional requirement of markings. The study results show the refinement of the visibility index in the road standard to incorporate adverse weather conditions. As a further study, extended experiments need to be carried out to incorporate various marking types and weather conditions.

기상조건 변화에 따른 노면표시 비드의 최적 배합비율 산정

이승규,이승현,최기주 한국도로학회 2012 한국도로학회논문집 Vol.14 No.3

Lane markings such as edgelines, centerlines, and lines that delineate lanes generally provide drivers with the various information for safe driving. Drivers can easily recognize the lane markings through the color differences between the markings and road surfaces during the daytime. However, it is a bit difficult for drivers to perceive them during the nighttime due to the lack of artificial lights. Although the glass beads with the 1.5-refractive index have been used to improve the visibility of the lane markings during the nighttime, it is still difficult for drivers to recognize the lane markings properly, especially during the rainy nighttime, which may often lead to traffic accidents. To improve the retroreflectivity and visibility of the lane markings during the rainy nighttime, the high refractive beads with the 2.4-refractive index are essentially required, but they do not work appropriately during the dry nighttime. Thus, the mixed materials with the 1.5, 1.9, and 2.4-refractive beads should be considered for the satisfactory implementation of the lane markings. This study reveals the best mixing rates of the beads by conducting benefit-cost analysis under various weather conditions in Korea. The analysis results show that the lane markings with the 100% of the 2.4-refractive beads provide the highest visibility of lane markings regardless of the roadway conditions, but the benefit-cost (B/C) ratio of the bead mixture is merely 0.46. The best mixing rate of the beads, from the highest B/C ratio viewpoint, was identified as the mixture with a 80% of 1.5-refractive beads and a 20% of 2.4-refractive beads. Some limitations and future research agenda have also been discussed. 노면표시에 도포된 굴절률 1.5 유리알은 야간 우천 시 효과적인 재귀반사를 수행하지 못하여 교통안전에 심각한 문제를초래하고 있다. 이를 극복하기 위해 습윤상태에서 효과적 재귀반사를 수행하는 굴절률 2.4인 우천형 bead와 건조 시 최적의 재귀반사를 수행해 내는 굴절률 1.9 bead를 혼합한다. 그러나 고성능의 굴절률 1.9와 2.4 bead는 기존 1.5 유리알에 비해 상당한 고가이므로 전량 사용하기에는 상당한 비용이 소요된다. 따라서 현장 설치 시에는 서로 혼합하여 사용하는 것이바람직하며, 최적 성능과 소요 비용을 고려한 적정 배합비율을 찾아내는 것이 중요하다. 본 연구에서는 다양한 비율로 혼합된 bead를 국내 고속도로의 길가장자리선에 설치하였을 때 발생되는 각각의 비용 및 편익에 따른 경제성 분석을 수행하였다. 분석 수행결과, 다양한 강수량 변화에도 높은 시인성을 유지하는 대안은 굴절률 2.4가 100% 구성된 차선으로 나타났으며, 경제성이 가장 높게 확보되는 대안은 굴절률 1.5가 80%, 2.4가 20%로 구성된 차선으로 B/C는 약 1.92 수준으로 도출되어 국내 고속도로 길가장자리선의 적용 시 가장 효과적인 대안인 것으로 확인되었다. 아울러 연구의 한계와 몇몇 장래 연구과제가 토의되었다.

일반도로 중앙분리대 측 백색 실선 도입 타당성 분석 연구

김다예,홍경식,이호원 한국도로학회 2018 한국도로학회논문집 Vol.20 No.3

PURPOSES: This study analyzes feasibility for application white pavement markings in the roadways with median barrier. METHODS : By reviewing numerous relevant laws, standards, and operational cases, the white pavement markings' excellence was demonstrated. Driver’s behavior was analyzed through a virtual driving experiment using driving simulator and field tests. RESULTS: First, white pavement markings are superior to yellow pavement markings in terms of visibility, economics, and safety. Second, as a result of virtual driving experiment, the color of line in the roadway with median barrier didn’t affect the driver’s behavior such as the average vehicle speed, the distance bias in the lane and the separation distance from the centerline. Third, field test demonstrated that the driver tended to recognize the median barrier as an obstacle. In addition, the central driving ratio in the lane was increased due to improving the visibility of line at night in case of the white pavement markings. CONCLUSIONS : The application of white pavement markings in the roadways with median barrier can enhance traffic safety by improving the visibility of line at night.

악천후 도로 시인성 개선을 위한 발광 차선 적용성 평가

이석기(Sukki Lee),박원일(Wonil Park),박기수(Kisoo Park),김용석(Yongseok Kim) 한국산학기술학회 2023 한국산학기술학회논문지 Vol.24 No.3

도로 교통사고로 인한 재산상의 피해 및 심리적 상실감을 감안 시 교통사고 방지를 위한 시급한 대책이 절실한 실정이다. 안개나 강우 등 기상 악천후는 도로 교통사고를 유발하는 주요 원인 중 하나이기 때문에 악천후 대응이 가능한 안전시설 설치로 사고를 미연에 방지할 필요가 있다. 본 연구는 도로 노면표시의 시인성을 향상시킬 수 있는 대안 기술로 발광 물질을 활용한 도로 노면표시의 현장 적용성을 평가한 연구이다. 현재 도로 노면표시 재료로 가장 빈번하게 사용되는 글라스비드 인입 재귀반사식 노면표시와 대비하여, 정상 기상 및 악천후 기상조건 환경에서 휘도를 척도로 시인성을 비교하였다. 평가결과, 차량 전조등이 없는 경우는 정상, 안개, 강우 조건 각각에 대해 4.57배, 4.73배, 4.1배의 시인성 향상을 나타냈으며, 차량 전조등이 있는 경우는 세 가지 조건에서 각각 1.07배, 1.39배, 1.02배의 시인성 향상을 나타냈다. 본 연구는 발광 재료를 사용한 노면표시가 현재 글라스비드에 비해 다양한 기상조건에서 우수한 시인성을 나타냄을 실증실험을 통해 규명하였고 기상악천후에 따른 시인성 저하 정도를 정량적으로 규명하였다. 향후 발광형 노면표시에 대한 비용효과적인 현장 적용 방안이나 장기 내구성에 관련한 추가적인 연구가 필요할 것으로 본다. Considering the property damage and psychological disorder resulting from traffic accidents, urgent remedies are highly required for preventing them. Adverse weather such as fog and rain conditions has been regarded as one of the critical factors of a traffic accident, so weather-responsive road safety facilities need to be installed. This study examined the applicability of pavement markings by utilizing a phosphorescent substance for visibility enhancement in response to adverse weather conditions. The markings were compared with widely used glass-bead encapsulated retro-reflective pavement markings to evaluate the visibility performance in terms of luminance using real road-scale facilities for adverse weather simulation. As a result, the visibility was improved by factors of 4.57, 4.73, and 4.1 under clear, fog, and rain conditions in the absence of vehicle headlights and by factors of 1.07, 1.39, and 1.02 in the presence of vehicle headlights, respectively. From study results, we validated the superior visibility performance of the photoluminescence lane marking compared to glass-bead encapsulated pavement markings. We also quantitatively evaluated the visibility degradation due to adverse weather compared to normal clear weather conditions. We recommended a cost-effectiveness study for site selection and long-term material robustness for future studies.

시뮬레이터를 이용한 감속유도 노면표시의 효과 연구

노관섭,이종학,김종민,장혜란 한국도로학회 2010 한국도로학회논문집 Vol.12 No.3

The purpose of this study is to establish how drivers react on different pavement markings in a driving simulator for speed reduction. For this,forty one people between the ages of twenty and seventy took part in this experiment. A study analyzed which patterns are effective to reduce a speeding. As a results‘, Peripheral Transverse Lines II’were the most effective treatment for reducing driving speeds in the driving simulator. This study carries an important meaning when presenting the effectiveness of speed reduction for perceptual countermeasure based on the human factors. Further research will be required to determine the long term effectiveness of these countermeasures due to concerns over drivers becoming too accustomed to implemented markings. Also, the color contrasts (for example, dark asphalt with white markings) can be considered. 본 연구는 시뮬레이터를 이용하여 속도감속 노면표시 유형별로 감속 효과가 어느 정도인지에 대한 연구를 수행하였다. 이를 위해서20~70대의 다양한 연령층으로 구성한 41명이 실험에 참여하였다. 구간별 기법에 따른 속도현황을 살펴보면, 노면표시 시작지점 및곡선시작점에서 Peripheral Transverse Line Ⅱ의 속도 감속효과가 가장 좋은 것으로 나타났다. 본 연구는 도로이용자의 인간공학적고려 요소를 바탕으로 운전자 시각특성을 고려한 감속유도기법 개발에 있어서 그 효과를 검증했다는 점에서 의의가 있다. 향후 연구로는 감속유도 노면표시가 장기적으로 운전자에게 효과적인지에 대한 검증이 필요하며, 색의 대비(예 : 흰색 노면표시에 검은색 아스팔트)에 따른 속도감속 효과가 있는지에 대한 연구도 필요하다.

Correlations between Refractive Index and Retroreflectance of Glass Beads for Use in Road-marking Applications under Wet Conditions

신상열,이지인,정운진,최용규 한국광학회 2019 Current Optics and Photonics Vol.3 No.5

Visibility of road-surface markings is one of the critical issues that should be secured for self-driving cars as well as human drivers. Glass beads are taking on the role of retroreflectors, and therefore are considered a necessity in modern pavements. In this context, retroreflectance is sensitively dependent not only on the refractive index of glass beads but also on that of the surrounding medium. This implies that the optimum refractive index of glass beads immersed in water, i.e. under wet conditions, is different from that of glass beads surrounded by air, i.e. under dry conditions. A refractive index of approximately 1.9, which is known to maximize retroreflectance under dry conditions, actually exhibits much poorer retroreflectance under wet conditions. This suggests that glass beads with optimal refractive index for wet conditions need to be installed together with those for dry conditions. We propose a facile but practical model capable of calculating retroreflectance of glass beads surrounded by an arbitrary medium, here water in particular, and experimentally verify its capability of assessing the refractive index of commercial glass beads. Changes in retroreflectance according to the mixing ratio of glass beads with different refractive indices are also discussed, in an effort to propose the proper use of glass beads produced for dry and wet conditions.

A Novel Method to Integrate Speed and Emissions Characteristics in Pavement Marking Design

홍승민,정소영,오철,박세리 대한토목학회 2018 KSCE JOURNAL OF CIVIL ENGINEERING Vol.22 No.12

Pavement marking is a popular method to reduce freeway off-ramp speed. The objective of this study is to develop a methodology for selecting the optimal pavement marking design that will improve traffic safety and reduce emission levels in the freeway offramp. Six pavement marking pattern scenarios on a freeway off-ramp were examined through the following sub-tasks. The first step focused on the testing of six selected scenarios for pavement marking design using a VR driving simulator to obtain driving behavior patterns. Next, the driving behavior pattern for each scenario was implemented in VISSIM, a microscopic traffic flow simulation, to extract the speed reduction for each scenario considering vehicle interactions. Then, the vehicle emission level of each scenario was evaluated by a Motor Vehicle Emission Simulator (MOVES). Through a multiple-criteria decision making model, the best pavement marking design scenario that was both eco-friendly and effective in reducing vehicle speed was selected. Study results showed that transverse line type is the optimal design of pavement marking that improves traffic safety while decreasing emission at a freeway off-ramp. The proposed methodology in this study would quantitatively support the selection of optimal pavement marking design that will promote both traffic safety and traffic environment.