BACKGROUND

Roadside safety hardware (RSH) such as guardrail is crash tested to assess the crashworthiness of the device. The current crash test criteria are contained in the AASHTO Manual for Assessing Safety Hardware (MASH), and all state departments of transportation (DOTs) are in the process of implementing MASH hardware on their systems. While MASH-tested hardware is available for the majority of applications, state DOTs and other transportation agencies may encounter situations where the approved RSH is not suitable for the location.

Transportation agencies may address these situations with special site-specific designs; however, no specific documentation of such practices is currently available, nor are guidelines on how transportation agencies should address these situations. Some examples of non-standard roadside applications could include modifying a crash-tested barrier to fit a location, using an older crash test standard, using less stringent testing criteria, and shielding or not shielding some obstacles at a location. Research is needed to develop guidelines for non-standard RSH applications where standard practices for crash-tested RSH cannot be used.

OBJECTIVES

The objectives of this research are the following:

• Identify situations where it is infeasible to use MASH devices for specific roadway criteria from state DOTs and other transportation agencies. 

• For the situations identified through Objective 1, assess whether non-MASH devices or MASH devices with less stringent roadway criteria can be used instead.

• Identify strategies for situations where MASH system designs may not be practical, such as environmental constraints, right-of-way limitations, and utility conflicts.

• Develop guidelines that transportation agencies can use to mitigate situations where MASH devices for specific roadway criteria cannot be used.