Strategies for sharing bottleneck capacity among buses and cars

In urban settings where space is at a premium, bus lanes can often times be created only via the conversion of existing general-use lanes. If buses are dispatched at low rates, the converted lanes will be under-utilized and squander road space. The bottlenecks within the city’s road network would then impart even greater delays to cars.The present paper addresses this problem by exploring novel ways in which buses and cars can share lanes within select bottlenecks. The details of a shared-lane strategy vary, depending upon certain details of its bottleneck. In all cases, the idea is to insert cars into a shared lane so as to put available road space to use without delaying buses. Ordinary lane conversions would occur elsewhere throughout the road network, and these would connect to the shared lanes within the bottlenecks.Analytical assessments unveil a wide range of cases for which the proposed strategies increase a bottleneck’s car-carrying capacity, as compared against reserving one of its lanes for buses only. Simulations of a real site indicate that significant reductions in car delays can result.

► Strategies are proposed for using bus lanes when bus flows are low.
► The strategies prioritize bus travel while maximizing car-carrying capacity.
► Models show that the ideas can enjoy broad application.
► A case study illustrates potential benefits.