5.2. Utilizing Production Curves for Estimation

Try these first

1. 1.

   Define cycle time in bulldozer operations.

   Hint

   Think about the different components that make up this total time.

2. 2.

   What is job efficiency?

   Hint

   Consider how often machines work effectively versus downtime.

3. 3.

   What determines variable cycle time?

   • Terrain
   • Stroke Length
   • Hammer Weight

   Hint

   Think about what conditions change during bulldozer operation.

4. 4.

   True or false: Job efficiency is always 100%.

   • True
   • False

   Hint

   Consider the time machines are actually running versus downtime.

5. 5.

   A bulldozer has a blade capacity of 3 cubic meters and operates with a cycle time of 5 minutes under ideal conditions. Calculate its productivity. Then, if it operates at 75% job efficiency, what is its adjusted productivity?

   Hint

   Don’t forget to factor in the job efficiency after finding the base productivity.

6. 6.

   Using a production curve, you determine that a bulldozer can achieve 8 loose cubic meters per hour at a certain dozing distance. If a correction factor of 0.8 is to be applied due to adverse conditions at the project site, what will be the real productivity?

   Hint

   Remember to multiply the ideal productivity by the correction factor to find the adjusted real productivity.