VISSIM 5.30-05 User Manual

6 The Traffic Network
Example 3 - Step 2
4 t = 0 s
x = 5 m
v = 180 km/h
grün = Lkw/Bus
green = HGV/Bus
4
5
Querverkehrsstörungen
für einen zweistreifigen Kreisverkehr
mit zweistreifiger Zufahrt
Priority rules
for a two-lane roundabout
with a two-lane entry
Spur 1
(lane 1)
Spur 2
(lane 2)
Legende (legend)
t: Zeitlücke
(min. gap time)
x: Weglücke
(min. headway)
v: max. Geschwindigkeit
(max. speed)
gestörter Querschnitt
(stop line)
störender Querschnitt
(conflict marker)
268 VISSIM 5.30-05 © PTV AG 2011
1-5
5 t = 3.6 s
x = 0 m
v = 180 km/h
rot = Lkw/Bus
red = HGV/Bus
The previously entered priority rules (Nos.1-3) are valid for all vehicle
classes. In the case where a long vehicle within the roundabout passes the
conflict area, the minimum speed condition (No.1) is not sufficient. It could
happen that vehicles entering the roundabout crash into an HGV/truck. To
avoid this, another conflict marker needs to be added (No.4) to the same
stop line as Nos.1-3 but valid only for long vehicles approaching the green
bar (in this case HGVs and Buses).
To finish off the priority rules related to lane 1 another one is needed to
consider entering vehicles having a lower acceleration capability than cars.
For this purpose priority rule No.5 is used. In contrast to all the existing
priority rules, this one needs a new stop line because a different set of
vehicle classes (HGV & Bus) is affected. It is placed at the same location as
No.2 but with a higher gap time of 3.6s.