BACKGROUND

The AASHTO Technical Committee on Roadside Safety is developing the next edition of the Roadside Design Guide (RDG).  The Roadside Safety Analysis Program (RSAP) was developed under NCHRP Project 22-09, "Improved Methods for the Cost-Effectiveness Evaluation of Roadside Safety Features," to update and enhance the cost-effectiveness analysis algorithms and procedures of the ROADSIDE software included in the RDG. Subsequently, under NCHRP Project 22-9(2), Roadside Safety Analysis Program (RSAP)-Engineer’s Manual, RSAP was revised and summarized in Appendix A of the 2002 Edition of the RDG. 

Since the release of RSAP, users have identified opportunities for improving the program and its interface for use in field applications that are beyond RSAP’s current capacity.  One particular area of concern is whether the default relationships and data tables embedded in the program reflect state-of-the-art insights regarding the probability of roadside encroachments, the severity of crashes, and the properties of roadside features. Research projects (such as NCHRP Project 17-22, Identification of Vehicular Impact Conditions Associated with Serious Ran-Off-Road Crashes) that were conducted after RSAP was completed may provide inputs to update the severity indices and encroachment rates.

Research is needed to develop a revised/updated version of RSAP and its associated documentation. The resulting upgraded interface should take advantage of increased computing capabilities to substantially enhance ease of use.

OBJECTIVES

The objectives of this project were to rewrite the software, update the manuals, improve the user interface, and update the embedded default data tables of the Roadside Safety Analysis Program (RSAP).

STATUS: Research is complete; final report is available as NCHRP Web-Only Document 319 at https://www.trb.org/Publications/Blurbs/182694.aspx.