Mahmoud Saffarzadeh - Professor, Faculty of civil engineering, Tarbiat Modares University
Mohammad Seyed hosseini - Professor,University of Science and technology
Hima Saki - Master Science Student, Faculty of Engineering, Islamic Azad University, South Tehran Branch

The first objective of this study is the evaluation of u-turn in advance of signalized intersection. First mentioned the comparison of direct left turn and right turn follow by u-turn by two factors, travel speed and delay, next simulated Real situation and compared to result of access point operation u-turn as alternative to direct left turn by delay, v/c ratio, LOS of signalized intersection, with use of case study field data. We concluded that When DLT volume is low, elimination of DLT and operate RTUT has an adversely affect the delay of approaches but In moderate and high traffic volume, vehicle making DLT suffer longer delay and travel time than those make RTUT, also LOS of signalized intersection improved after DLT elimination.The findings of this study are helpful in providing local and state transportation agencies with recommendations for the design and selection of RTUT in advance of signalized intersection

u-turn, DLT, Aimsun, RTUT, signalized intersection