The Journal of The Korea Institute of Intelligent Transport Systems (한국ITS학회 논문지)

The Korea Institute of Intelligent Transport Systems (한국ITS학회)
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A Study on Application of TPCLT(Twice Per Cycle Left-Turn) for a Signalized Three-Leg Intersection

3지 교차로의 TPCLT(Twice Per Cycle Left-Turn) 적용 방안 연구

  • Han, Dajeong (Dept. of Civil & Environmental Engr., Incheon National University) ;
  • Kim, Eungcheol (Dept. of Civil & Environmental Eng.r, Incheon National University)
  • 한다정 (인천대학교 일반대학원 건설환경공학과) ;
  • 김응철 (인천대학교 도시과학대학 건설환경공학부)
  • Received : 2018.10.22
  • Accepted : 2019.02.18
  • Published : 2019.04.30
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Abstract

TPCLT is a advanced signal system that serves twice left turn phases during the same cycle. TPCLT can be a useful where the left turn traffic volume is high and the length of the left turn lane is short. This study examined the effectiveness of TPCLT in reducing delay for a signalized three-Leg intersection and proposed the application of TPCLT signal system. 108 scenarios with different traffic volumes were created. This study analyzed the control delay of the three-Leg intersection in case TPCLT is operated and non-TPCLT is operated. As a result of analysis, it was shown that TPCLT was effective in most of the scenarios. When traffic volume ratio of the left turn is 30~40%, TPCLT was more effective at reducing the control delay. The study result shows significant delay reduction for the left turning traffic and it is approximately 50 seconds. The opposing movement's average control delay increased 2 seconds. The effect of TPCLT on the length of left turn lane was analyzed. As a result, it is found that TPCLT is effective when the length of left turn lane is 30%~60% compared to that of conventional three leg intersection operations.

TPCLT란 한 주기에 두 번의 좌회전 신호를 제공하는 신호 운영 방법으로 좌회전 교통량이 많고 적정 좌회전 차로 길이 확보가 어려운 교차로에 적용가능한 신호 운영 개선 방법이다. 본 연구에서는 TPCLT의 적용 방안 연구를 위해, 3지 교차로를 대상으로 방향별 교통량의 변화를 준 시나리오를 구축하여 TPCLT 적용 시와 3현시 최적화 신호 적용 시 교차로의 제어지체를 분석하였다. 분석결과, 대다수의 시나리오에서 TPCLT 적용 시 지체 감소 효과가 높은 것으로 나타났으며 특히 좌회전 교통량이 30~40%인 경우 지체 감소가 큰 것으로 나타났다. 이때, 접근로별 지체는 TPCLT 신호를 적용한 방향의 경우 50초 이상 지체가 감소하였으며 대향차로는 약 2초의 미미한 지체 증가를 나타냈다. 좌회전 차로 길에 따른 TPCLT 운영 효과 분석결과 좌회전 차로 길이를 적정 좌회전 차로 길이의 30~60%를 확보한 경우 TPCLT 적용 시 지체 감소에 효과적인 것으로 나타났다.

Keywords

References

  1. Corey et al.(2012), "Improving Intersection Performance with Left Turn Phase Reservice Strategies," International IEEE Conference on Intelligent Transportation Systems, 2012 15th, pp.406-408.
  2. NAZTEC(2000), TecNote 1102 - Twice Per Cycle Left-Turn & Double Cycle Operation.
  3. Oh et al.(2017), "A Study of TPCLT(Twice Per Cycle Left-Turn) Operation Impact at Three-legged Signalized Intersection," The Korea Institute of Intelligent Transport Systems, vol. 16, no. 3, pp.50-58.
  4. SHA(State Highway Administration)(March 2011), Traffic Signal Phase Sequence Guidance Document, p.27.
  5. TRB(Transportation Research Board)(2015), NCHRP REPORT 812 Signal Timing Manual(Second Edition), pp.9-4,12-9,12-10.