The concept of aggregate concrete is that of inert filler within a concrete mix. But if you give careful consideration, then it will reveal a major role as well as influence that it plays in the properties of concrete. This might be both fresh and hardened. The changes in gradation, the size, weight of the unit and content of moisture are the factors that can change the character and performance of the concrete mix. The important thing about selection of aggregate is economy. You can save a lot of money if you give select the maximum size that is allowable for the aggregate. If you use large and coarse aggregate, then it will typically lower the cost because it reduces the requirement of cement which is an expensive material.
Why use aggregate in concrete?
The use of aggregate concrete is done mainly due to the economic reasons. It also gives stability to the hardened concrete. The cement paste has a high shrinkage potential when compared to the hardened concrete. It is important to control the shrinkage of the concrete material as there is an increase in cracking and shrinkage potential together. If there is higher shrinkage, it will mean more cracking. This happens when the concrete is restrained to move with the base materials that are beneath. The increase in the paste quantity reduces volume of aggregates per unit. Hence, the shrinkage of the mixture increases. It is also possible that the increase in shrinkage if combined with restraint of concrete section may be an addition to the cracking of a concrete section.
Factors to be considered selecting aggregate
- Basically, the aggregates comprise of 6o% to 80% of aggregates. Hence, they must be selected properly so that they are durable. They have to be blended in such a way that they are optimally efficient.
- The aggregate concrete has to be properly controlled so that they produce a strong, workable, finished and durable concrete. The ingredients required for conventional concrete falls in a proportional range.
- You need to make sure that the producer of concrete purchase aggregate that is of good quality. It should be verified by regular tests as per the standard specifications.
- The aggregate that is of good quality should be free of absorbed chemicals that are harmful. It should be free of coatings of clay or anything other than is contaminating. All this can affect the hydration of cement or reduce the paste aggregate bond.
- The aggregates that need to be avoided are the ones that are susceptible to get split. Even those that have significant quantities of both soft and porous materials.
What are the advantages?
Usually, the pathways, driveways, sidewalks and patios are very decorative. But how are they achieved? This is only by the use of aggregate concrete that is making the floors by removing the top layer on concrete. This is done so that the color and the texture are revealed. These exposed concrete floors are quite durable and are resistant to skid on the floors. The benefits are:
- You can get decorative effects at an affordable cost with the help of aggregate concrete. This is because very few additional materials are required for concrete. You may just need few decorative aggregate or sprayer and a garden hose.
- The procedure to construct it is very simple and anyone who has the experience in handling concrete can easily do it.
- The surface that is made out of aggregate concrete is whether resistant and lasts long. It is also resistant to skid on the surface.
The best part is that it suits the other decorations that you have done all around. You also do not need to any additional maintenance except that of occasional cleaning with plain water. They have to be only resealed after few years.