7.3. Principles of Mixture Proportioning for HPC

Try these first

1. 1.

   What is meant by the term 'Target Performance Specification'?

   Hint

   Think about what standards we set for the concrete's performance.

2. 2.

   Name one benefit of using Supplementary Cementitious Materials in concrete.

   Hint

   Consider the context of improving concrete's longevity.

3. 3.

   What is the typical water-binder ratio for High Performance Concrete?

   • 0.45-0.50
   • 0.30-0.35
   • 0.20-0.25

   Hint

   Lower values lead to higher concrete integrity.

4. 4.

   True or False: The use of trial mixes is unnecessary in HPC design.

   • True
   • False

   Hint

   Consider how real-world testing helps confirm initial designs.

5. 5.

   Calculate the required amount of water if a mixture has a total binder content of 500 kg/m³ with a w/b ratio of 0.30.

   Hint

   Use the formula for water-binder ratio.

6. 6.

   Critique a proposed concrete mix that includes a very high water-binder ratio of 0.50 for an HPC application. What potential issues could this pose?

   Hint

   Consider the balance of strength and permeability when evaluating.