The legibility of a road is an important aspect of road safety and it is directly influenced by the landscape. The research need is to identify the possible landscape layouts which would improve the legibility of the road and therefore also the overall safety.
On that base, types of landscape layout will be recommended to increase the safety of dangerous road's sections and to improve projects of new roads.
The project has following objectives:
- Improving road user's safety by strengthening the legibility of road course with plantations
- Meeting the K28 target of the Road safety national policy (VESIPO)
- Defining the role of the landscape in the legibility of a road and its influence on the safety.
- Conceiving an analysis tool allowing locate and identify problems of safety due to a bad legibility of the road in the landscape
- Proposing solutions which require landscape modifications
The approach proposed in this study will take place in the following stages:
• Bibliographic research
• Analysis accident-logical
• Selected Case Studies
• Synthesis of information collected
• Development of recommendations and bases for a standard
This study confirmed that landscape design has a great potential to increase road safety. The correct understanding of a driving context is a decisive factor that landscape design can contribute to improve.
The case studies carried out in several cantons have provided strong arguments in the sense of working hypothesis but could not reach unambiguous link between landscape design and the occurrence of accidents. Each case is unique and requires a specific understanding of accident dynamics and the interferences between different parameters.
It was not possible to quantify the effects of landscape design on user behavior or accident rate on a specific road section. The researches carried out in other European countries faced similar difficulties. The results obtained could be used within the implementation framework of SN 640010 standard "base for the analysis of accidents" and the draft standard SN 640012 "Road Safety Audit (RSA)."
It seems important to further introduce or develop the concept of road readability in Switzerland, especially since experience in this field is still lacking. The implementation monitoring of successful projects would document the issue and point out the most effective actions. The research projects and achievements made abroad for this purpose shall be monitored carefully, for example, by further exchanges with neighbouring countries.
The following items are still insufficiently documented and require additional investigation:
- Quantification of landscape design impact on road safety
- Quantification of road layout impact on the readability of infrastructure
- Security audit processing for the design of road projects as well as for the existing network
- Readability concept implementation in urban environment
The integration of specialists or experts (landscape architects, psychologists, accident specialists) into the investigation, design or auditor teams seem to be necessary to achieve valuable results as well as to gather feedback in order to improve the level of knowledge on this issue.