What is the minimum pavement width for a 180 degree turn?

What is the minimum pavement width for a 180 degree turn?

• A. 60 ft
• B. 70 ft
• C. 78 ft
• D. 75 ft

Answer: (D)

To complete a 180-degree turn, you need space for the vehicle to follow a semicircular path, so the pavement width must at least match the vehicle’s turning diameter. The turning diameter is the full width of that circular path, so the minimum width is the smallest width that still allows the turn without hitting the edges. For the typical vehicle scenario in this test, that turning diameter is about 75 feet, making 75 feet the smallest width that works. Wider options like 78 feet are more than needed, but not the minimum, and narrower options such as 60 or 70 feet would not accommodate the turn. Therefore, 75 feet is the minimum pavement width.

To complete a 180-degree turn, you need space for the vehicle to follow a semicircular path, so the pavement width must at least match the vehicle’s turning diameter. The turning diameter is the full width of that circular path, so the minimum width is the smallest width that still allows the turn without hitting the edges. For the typical vehicle scenario in this test, that turning diameter is about 75 feet, making 75 feet the smallest width that works. Wider options like 78 feet are more than needed, but not the minimum, and narrower options such as 60 or 70 feet would not accommodate the turn. Therefore, 75 feet is the minimum pavement width.