What is the maximum slope for recoverable fore-slopes according to standards?

• A. 3H:1V
• B. 4H:1V
• C. 2H:1V
• D. 5H:1V

Answer: (B)

The maximum slope for recoverable fore-slopes is typically defined as 4 horizontal to 1 vertical (4H:1V). This standard is established to ensure safety and stability on roadways and embankments, allowing for a gradual slope that can help prevent erosion and provide adequate recovery space for vehicles in the event of a loss of control.

A 4H:1V slope is categorized as recoverable, meaning that if a vehicle were to veer off the roadway, it would have a tendency to regain control rather than rolling over or sustaining significant damage. This slope allows for a buffer zone that provides a safer transition between the roadway and surrounding terrain.

In contrast, steeper slopes may not adequately provide this safety margin, and shallower slopes are often not practical for the necessary drainage and stability requirements associated with transportation infrastructure. Thus, the use of the 4H:1V standard is crucial for the design and maintenance of safe roadway edges.