Preparation of concrete should include adding the correct proportions of water, Portland cement, and aggregate, by volume or by weight, using a concrete mixer, mortar box, or wheelbarrow.

Process/Skill Questions:

• What are the safety precautions and procedures to follow when using a concrete mixer?
• What are the ingredients in a concrete mix? How are they batched and mixed?
• What is the proportion of materials in a given concrete mix?
• What are the characteristics of properly mixed concrete?
• What is the procedure for hand-mixing concrete in a mortar box?
• What are the similarities and differences between using a mortar box and an electric mixer?
• What is the importance of mixing concrete?
• Why and how should water be measured when mixing concrete?