TRCLC 15-9
Impact of Access Management Practices to Pedestrian and Bicycle Operations and Safety
PIs: Deo Chimba and Kimberly Triplett (Tennessee State University)
Summary:
The study focused on the impact of access management to Pedestrian Safety. Poor access management has been linked to certain types of crashes, the fact which is evident from the crash patterns in Tennessee. There was a need therefore to address how pedestrian safety is impacted by different access management practices in the state. The study evaluated and identified the correlation between access management practices in Tennessee to pedestrian crash types, crash frequency by producing the following for dissemination:
- Established relationship between access management features and crash frequency through statistical analysis.
- Developed safety performance functions (SPFs) that can be used to evaluate the safety impacts of various access management and driveway-related configurations on Tennessee corridors.
Problem:
The thrust of this proposal falls under the vital role which transportation system and network play in ensuring livability of communities through safe and efficient transportation services. In particular, this study focuses on the impact of access management (AM) practices to the operations and safety of pedestrians. Key elements focused on crosswalk, sidewalks, shoulder, posted speed limit, median type and access density. Attention was also paid to access management practices that impact pedestrians including traffic control type, signal density, two-way left turn lanes (TWLT), and circulation approaches. All these can affect safety and operations of pedestrian crossing and maneuvering. The need was to address how pedestrian operations and safety are impacted by these access management practices.
Research Results:
Four variables including AADT, access density, percentage of trucks and the presence of TWLT were found to be positively associated with the pedestrian crash frequency. Variables such as the presence of median, presence of crosswalk, presence of shoulders, presence of sidewalk and high speed limit had negative coefficients, hence their increase or presence tends to decrease pedestrian crashes. It could therefore be concluded that though these variables had some influence on the pedestrian crashes, access density, crosswalk, sidewalk and speed limit were the most statistically significant variables that determined the frequency of the pedestrian crashes. Overall, the study found that pedestrian safety is affected by access management practices, especially the distribution of access points. Though critical to commercial and business access, if not planned well, access points may lead to severe pedestrian crashes. Therefore, access density can be reduced by re-routing the entrance/exit point to and from the business areas to minimize conflicts. In addition, divided roadways with raised medians are much safer than TWLT or undivided roadways for pedestrian safety. Speed limits along commercial areas with significant pedestrian movements should be kept not above 40 mph as beyond that the risk to pedestrian safety increases.