What is a pile or mound of material used to limit the force of a vehicle on an elevated roadway called?

The term that describes a pile or mound of material used to limit the force of a vehicle on an elevated roadway is known as a berm. A berm is typically constructed at the edge of a roadway or elevated area to provide protection against vehicles straying off the road, helping to absorb impact energy and prevent damage to both the roadway and surrounding areas. Furthermore, it can offer a degree of support and can also act as a drainage feature to direct water away from the road.

In contrast, an embankment generally refers to a raised structure made from earth or other materials, primarily used to support a roadway or railway, rather than serving solely as a protective feature. A barrier is a broader term that could encompass various types of obstructions meant to prevent passage or access, but does not specifically describe a mound of material. A retaining wall is designed primarily to hold back soil or other materials, preventing erosion and ground failure, rather than functioning as an impact-limiting mound.