Multilane Microscopic Modeling to Measure Mobility and Safety Consequences of Mixed Traffic in Freeway Weaving Sections

Table 1

Research summary of safety in mixed traffic environments.

Reference	Safety parameters	Findings
[45]	(i) Time-to-collision (TTC); (ii) nondimensional warning index	ACC strategy can prevent vehicle gaps from reducing to an unsafe level in different driving scenarios
[46]	(i) Time Exposed Time-to-collision (TET); (ii) Time Integrated Time-to-collision (TIT)	90% reduction of rear-end collision risks due to CACC system
[47]	(i) TTC; (ii) postencroachment time (PET)	Low CAV penetration showed an increase in potential conflicts at lower headway and signalized intersections; higher CAV market share showed a global decrease
[48]	(i) TET; (ii) TIT	Degradation from CACC to ACC had a significantly negative impact on longitudinal safety
[43]	(i) TTC; (ii) PET	Estimated conflict rates reduced with a gradual increase in market share of CAV and finally reduced by 90–94% at 100% CAV penetration rate
[49]	(i) TTC; (ii) TET; (iii) TIT	Mixed traffic flow can induce higher longitudinal collision risk at low market penetration of ACC driven vehicle due to individual heterogeneity
[50]	(i) Number of conflicts; (ii) longitudinal volatility	Substantial safety improvement was observed at market penetration higher than 40%