20.3. Issue: Strength too low

Try these first

1. 1.

   What does a high water-cement ratio lead to in concrete strength?

   Hint

   Think about the relationship between water and cement.

2. 2.

   Which factor is important to check when mixing concrete?

   Hint

   Consider how precise measurements affect the mix.

3. 3.

   What is a major cause of low concrete strength?

   • Excess cement
   • High water-cement ratio
   • Correct batching

   Hint

   Think about the effect of too much water.

4. 4.

   True or False: Accurate batching is critical for achieving the desired concrete strength.

   • True
   • False

   Hint

   Remember why precise measurements are needed.

5. 5.

   You tested a concrete mix and found it only reaches 18 MPa strength, below your target of 25 MPa. List three ways you would adjust your mix.

   Hint

   Think about what is missing or too high in your mix.

6. 6.

   During a slump test, you found the concrete mix was too stiff. What steps can you take to improve its workability?

   Hint

   Workability means how easy it is to pour and shape the concrete.