The redesign of existing roads in urban areas increasingly included the implementation of multipurpose lanes. However, till now, both adequate assessment criteria and an overview of operational experiences with this new element are missing.
In order to achieve the above mentioned objectives hypotheses regarding the effectiveness an expediency of multipurpose lanes will be formulated an evaluated.
The main objective of this project is the elaboration of criteria for the general assessment of multipurpose lanes. Multipurpose lanes are located in the middle of roads. They are accessible for both motor vehicles and slow moving traffic.
The objective of this study is to propose warrants for the application of multipurpose lanes regarding all traffic flow, road operation and safety. Adequate assessment procedures for the arrangement of multipurpose lanes on main roads in town centrums will be worked out. Furthermore, fundamentals for a future standardisation shall be prepared.
Through the testing of hypotheses and questions, which will be developed as a result of analysis of literature and realised examples, application criteria for the placement of multipurpose strips are worked out.
The examination of the formulated hypotheses and question is carried out as follows:
Priority 1: By evaluating literature and realised examples
Priority 2: Through discussions with experts
Priority 3: Targeted field investigations
The study enabled the following main findings to be established:
Multi-purpose lane usage is mostly driven by the following objectives:
- Improvement of crossing possibilities for pedestrians
- Improvement of the situation for left turn-offs for motorised traffic (MT) and / or cycle traffic
- Improvement of crossing possibilities for cycle traffic
- Reduction of the separation impact of a road
- Avoidance and / or overtaking possibility (MT / light two-wheeled traffic) for MT
- Design element (for the visual ordering of the road-space)
The minimal length of a multi-purpose lane should not be less than 50 m. Short multi-purpose lanes are not identifiable as such and are problematic in terms of arrangement and design.
Multi-purpose lanes should not have a minimal width less than 1.50 m (2.00 m for crossing cycle traffic, 3.00 m for cycles with trailer). Widths in excess of 3.00 m are in general not functional.
A multi-purpose lane is especially appropriate for situations where a need for left turn-offs exists over a longer road stretch for multiple accesses.