Working with concrete should be done carefully in order to achieve the best possible results. This means that it has to be mixed, transported, and handled well. All processes should be well-coordinated, especially when it comes to placing or finishing. As a rule of thumb, concrete shouldn’t be poured faster than it could be spread or the results won’t be as good.
The process of placing concrete should start along the perimeters, with the other end being a previously poured upon concrete. This is especially true when constructing slabs. Never pour concrete in different piles and then work and level them together. In the same way, it shouldn’t be poured in large piles and then moved horizontally to its final position.
Concrete Consolidation Techniques
In most cases, concrete is poured in forms before consolidation. Consolidation makes fresh concrete more compact as it molds within the forms or around reinforcement and embedded items to do away with entrapped air, honeycombs, and stone pockets.
To consolidate the concrete, either external or internal vibration is used. By using vibration, the friction inside the concrete and between its aggregates is destroyed temporarily. At which point, concrete acts like most liquids. It slowly settles in the form through gravity with air voids rising easily towards the surface.
Concrete Finishing Techniques
Concrete structures that are used out in the open, such as roads, highways, driveways, and patios require finishing. Concrete slabs are finished in different ways, depending on how you want to use the surface. Among the most common concrete finish techniques used today are the ones that integrate different textures and colors into the final output, such as in the case of patterned or stamped concrete and exposed aggregate finishes.
Other times, surfaces may only need simple finishing, such as when the screed and strike off techniques are used. These two techniques provide elevation and contour on the surface. There are other techniques used, more particularly the broom, float, and trowel finish.
Types of Concrete Finishing
There are concrete finishing techniques that are easily carried out and they make concrete more functional than they could have been without them. The most common concrete finishing techniques are:
- Screedingand strike off
These concrete finishing processes involves the cutting off of excess concrete so as to achieve the proper grade for the slab’s topmost surface. Concrete is cut using a straight edge moved across it to saw it.
The bull floating finishing technique eliminates low and high spots while embedding large aggregates right after the strike off process. The end result creates straight, long-handled edges across the surface.
Jointing is a technique used to eliminate random cracks on the concrete. These joints are created by inserting wood, metal, and plastic into the concrete before it hardens. Alternately, a hand groover or performed joint may also be used. Saw cut joints may also be used on the concrete to make it strong and hard enough to withstand raveling.
Troweling is a process that makes the concrete smoother, harder, and denser. Troweling usually follow concrete floating and must not be done on surfaces that haven’t been floated.