Which table in the AASHTO Green Book provides desirable lane change and deceleration distances for auxiliary lanes?

• A. Table 9-19
• B. Table 9-20
• C. Table 9-21
• D. Table 9-22

Answer: (B)

The choice of Table 9-20 in the AASHTO Green Book is accurate because this table specifically details acceptable lane change and deceleration distances for auxiliary lanes. These measurements are essential for ensuring safe and efficient merging and diverging of vehicles in the context of highway design, as they help facilitate smooth transitions between travel lanes and auxiliary lanes, such as those used for entering and exiting highways.

When designing highways, understanding the appropriate distances for lane changes and deceleration is crucial for accommodating driver behavior and enhancing safety. Table 9-20 provides guidelines based on vehicle speeds and roadway conditions, which are vital for traffic flow and accident prevention. This information serves as a critical resource for engineers and designers when assessing the geometry and operations of highway systems.

The other tables mentioned do not focus specifically on the lane change and deceleration distances for auxiliary lanes, which makes them unsuitable for this particular aspect of roadway design.