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onsider the geometric and traffic characteristics shown below Approach Width Peakhour Approach Volumes Left Turn Through Movement Right Turn Conflicting Pedestrian Volumes PHF ssume the following saturation flows Through lanes Through right lanes Left lanes Left through lanes Left through right lanes 1 600 veh h In 1 400 veh h In 1 000 veh h In 1 200 veh h In 1 100 veh h In North 56 ft 133 420 140 900 0 95 South East 56 ft 68 ft 73 168 373 563 135 169 1 200 1 200 0 95 0 95 he Webster method can be used to find the phase lengths and total cycle length for the intersection When calculating the ph engths ensure that enough green time is provided to allow for pedestrian movement Assume each of the four approaches is ivided into a left lane a through lane and a through right lane Assume the lost time due to acceleration and deceleration dur ach phase is 3 5 seconds and the time lost due to the red clearance interval between each phase is 1 5 seconds Also assum e curb to curb distance is 56 ft when pedestrians travel during the N S phases and 68 ft when pedestrians travel during the E hases Finally assume pedestrians walk at a speed of 3 5 ft s through a crosswalk of width 10 ft S West 68 ft 134 516 178 900 0 95 se the phase lengths and total cycle length to determine the queue service length in s for each phase assuming the proporti f vehicles arriving during the green interval is 0 70 for the north and south approaches and 0 90 for the east and west pproaches hase 1 N S left turn mase 2 N S through through right turn S