Which condition indicates insufficient mixing and low binder content?

• A. Stiff Mix
• B. Lean Mix
• C. High Slump in Truck
• D. Steam Rising from the Mix

Answer: (B)

Lean mix is when there isn’t enough asphalt binder relative to the aggregate. That low binder content makes the mix stiff and hard to work with, and it means the mix won’t coat the aggregate properly, which is a sign of insufficient mixing and low binder content. Among the options, that descriptor directly communicates the shortage of binder, whereas the other conditions point to different issues: a high slump in a truck implies excessive workability and potentially too much binder or moisture, steam rising indicates moisture in the mix, and a stiff mix describes the result but isn’t the specific label for low binder content. So lean mix best describes the condition of insufficient mixing with low binder content.