---
Created: 2024/05/05 11:08
---
# Concrete mix design

It is process of preparation of concrete with suitable proportion of ingredients. Each ingredient consists of different properties.

## Why concrete mix design

- To achieve specific strength characteristics.
- To meet required durability.
- To attain workability of fresh concrete.

## What is characteristics strength

- Cube test.
- Not more than 5% of the test results are expected to fall below threshold.
- Compressive strength: $M25$ -> $25 MPa$; `M` for mix, `25` for `25 MPa` compressive strength of that concrete. Usually increases with decrease of mixture ratio.

## Notes

- Chemical reaction occurs between water and cement. Aggregates make the process faster.

## Questions

- What is workability?
- What is durability?
- What is admixture?
	1. Improve workability.
	2. Faster strength gain.
- Where is Standard Concrete is used?
- Where is High Strength Concrete is used?
- What is 1:5:10?
	- Cement, sand, and aggregates ratio. Or, Cement, fine aggregates, and coarse aggregates.