Mixing cement with aggregates and water to create concrete seems like a straightforward process. However, there are ways to do it properly that will improve the quality and durability of the concrete.
Properly mixing the ingredients will create a strong product that will last many years. If you’re working on your own projects, follow these tips on the right way to mix concrete and make your projects stronger and more durable.
Tools needed for mixing concrete
- Rubber gloves
- Dust mask
- Large bucket
- Plastic or steel sheet
- Stiff-bristle brush or broom
How to mix concrete properly
The first step is to empty the cement bag into a wheelbarrow (or another mixing container). Cut open the bag of cement and pour it into the wheelbarrow. Scoop out a few cups of cement and keep them aside.
Pour a 10cm layer of sand onto the steel or plastic sheet – this will be the mixing area. The guidelines on the cement bag will have suggestions for the right quantities of sand and gravel per bag of cement.
Using a shovel, sprinkle the cement from the wheelbarrow over the sand. Mix the two dry ingredients together until a uniform colour is achieved. If your concrete has gravel or stones, mix these into the cement and sand next.
Measure out the specified amount of water (according to the instructions on the cement bag) and keep it in a bucket. Make a well in the dry ingredients with the shovel and pour about 90% of the water into the well – the remaining water can be added later if the concrete is too dry.
Mixing the wet and dry ingredients
Using a shovel, pull small amounts of dry ingredients into the water and mix thoroughly. Keep mixing small amounts with the water at a time, until all of it is wet. Continue mixing thoroughly and add the rest of the water if needed.
If you pull the shovel through the wet cement mix and the sides of the trench crumble, then your mix is too dry. Add one cup of water to the concrete and mix well. On the other hand, if the trench sags and fades too quickly, then your mix has too much water. Add a cup of cement and mix thoroughly until the concrete has the right consistency.
The sides of the trench should support themselves and the mix should become shiny when patted with the shovel. Your concrete is now ready to be poured or laid.
Cleaning your tools and equipment
Once you have poured your concrete, scrape off any leftover mix from your wheelbarrow, shovel and steel sheet and place it in a bag. Hose down your tools and equipment with water. Using the stiff-bristle brush, scrub the residual concrete off properly – any left on the shovel or wheelbarrow will dry and harden, making it almost impossible to remove.
The rinse water can be harmful to grass and plants so avoid hosing down your tools on a grassy patch or near plants. You can rinse off tools in a drainage ditch where the water will be able to flow away from the construction site.
LafargeHolcim is a leading building materials and solutions company that has been operating in international markets for decades. We produce cement and aggregates for construction projects, ranging from small affordable housing developments to large-scale infrastructure projects such as high-rise buildings, dams and bridges.
LafargeHolcim Tanzania has been supplying the country and neighbouring countries with our world-class Tembo cement brand for over 30 years. Our head office and fully-integrated plant are located in the Mbeya Region at Songwe in Southwest Tanzania.
At LafargeHolcim Tanzania, we believe customers come first. We listen to your specific requirements to supply and develop the best solutions for your needs. As the new leader in building materials, you can also rely on our cutting-edge research and development capabilities that have resulted in the finest materials for your construction projects, whether large or small.