What is the primary focus of Chapter 9 in the AASHTO Green Book?

• A. Vertical alignment
• B. Intersection geometry
• C. Pavement design
• D. Traffic control devices

Answer: (B)

The primary focus of Chapter 9 in the AASHTO Green Book is intersection geometry. This chapter provides guidelines and standards for the design and layout of road intersections, which are critical components of the roadway system. Proper intersection design is essential for ensuring safe and efficient traffic movement, accommodating various modes of transportation, and minimizing conflicts between vehicles and pedestrians.

Key aspects covered in this chapter include the geometric design of intersections, the arrangement of lanes for turning movements, sight distances, and the balancing of traffic flow. Good intersection design can help reduce accident rates and improve overall traffic safety. Understanding these principles is fundamental for civil engineers who work in transportation planning and roadway design, making this chapter vital for effective traffic management and roadway functionality.

Other chapters in the AASHTO Green Book cover different aspects of road design, but Chapter 9 is distinctly focused on the complexities and nuances associated with intersection geometry specifically.