What is the purpose of barriers in highway design?

The primary purpose of barriers in highway design is to prevent vehicular penetration and minimize injury risks. Barriers, such as guardrails or concrete walls, are strategically placed to protect motorists from hazards like steep embankments, cliffs, or oncoming traffic in the event of a collision. They provide a critical safety feature by absorbing impact and redirecting vehicles back onto the roadway, thus significantly reducing the likelihood of severe injuries or fatalities in accidents.

While improving road aesthetics can be a consideration in some cases, it is not the primary function of barriers. Traffic flow is more impacted by road design and traffic management strategies rather than by barriers, and speed limits are indicated by signage, not barriers. Overall, the main focus of highway barriers is on safety and injury prevention, making this the correct choice.