Tips for Concrete Construction Projects
The following brief overview on the concrete construction industry is provided to you to give a basic understanding of what concrete construction is.
Concrete is made of cement, sand and gravel or other coarse aggregate. Cement is a binding agent and the ingredient in cement that holds the concrete together.
Mixing and Curing the Concrete
The first step in preparing for concrete construction work starts with mixing the concrete. Adding the right amount of water to the mix and curing the concrete properly are two basic concerns. V. Rivera Concrete, with its years of experience, mixes the perfect concrete mixture ensuring the proper smoothness and strength of the hardened concrete.
As important as the proper mixture of wet concrete is the proper curing time. As the mix dries, it hardens. However, the drying, or ‘curing,’ should be gradual, otherwise the concrete may crack. There are several ways to slow down the curing of the concrete. The slower the evaporation of the water in the concrete is, the stronger the concrete becomes. Sometimes, plastic is used, with water sprayed on the surface after the first few hours, is utilized as it slows down the curing. V. Rivera Concrete ensures that the concrete is properly cured every time.
Bonding of the Concrete
Any surfaces that the concrete needs to bond to should be moistened just before the concrete is poured. For example, a joint can easily separate if this is not done and and will result in cracking or a defective product.
Example Steps in Basic Concrete Construction of a Patio
(These instructions are only for a basic overview and not meant to be followed as some steps may be omitted.)
- Calculate amount of concrete required.
- Excavate 4 to 6 inches depending on whether you live in an area where the ground freezes and thaws. In the North, the two bottom inches are for a bottom layer of gravel to prevent cracking when the ground thaws and the other four are for the concrete. A grade for water runoff must be made that slopes away from the house. The grade should be about 1 in. for every 4 ft.
- A form must be built to hold the gravel and concrete. The form should be sunk into the excavated area. If the concrete patio is to be flush with ground level, the top of the form should be level with the ground.
- Install gravel and tamp it down. Rebar reinforcing must be built approximately in the middle of the 4 inch-thick concrete slab you are constructing. Reinforce the rebar with 2 in. thick flat pieces of rock.
- When installing the rebar reinforcing, make a grid by putting them every two feet from front to back and also left to right of the area that the concrete will be poured. Wire them together at the intersections.
- Mix the concrete.
- Pour concrete and add filler rocks as you go. Pour as fast as possible. Preparation is crucial here.
- Use a screed (flat board) to level the surface by sliding it along the top of the form boards.
- Cut initial control joints (the grooves in the concrete) at about every 3-4 feet 2 in. deep.
- A watery layer should appear on the surface. Wait to proceed until after this watery layer evaporates.
- Even out any lumps on the concrete patio with a float (a flat tool with a handle).
- Finish the control joints begun in Step 9. Use a jointer (a tool specifically made to create control joints) to make a clean groove, about 1 in. deep
- Finish the concrete patio surface with design elements.
- Lay plastic over the new concrete patio to prevent the concrete from drying too quickly. Keep the plastic on for a week even though concrete does not fully cure for three weeks. Do not subject the concrete to undue stress before three weeks. The wait time for sealing varies by the product being used.
- If you anticipate a large water runoff from the patio and that it may cause problems, you may want to install a drainage system before laying the concrete patio. Drains meant especially for patios, called “linear drains,” tie into the drainage system for your yard.
Tips For Concrete Construction Projects
- Avoid skin contact with concrete, and do not inhale the dust.
- Wear the right attire. Use gloves, kneeling boards, long-sleeved shirts, goggles, face masks, long pants, and protective boots, etc.
- If bricks will be laid on the concrete slab, dig an extra 2 1/2 in.– 2 in. for the bricks and another 1/2 in. for the mortar between the bricks and concrete. Then, the tops of the bricks will be flush with the ground.
- Any extra stone that you may want to dispose of can be washed and incorporated into the concrete to take up space and save on concrete usage.
- During construction of the form, the use of tarps to cover the area can prevent debris from falling in on the concrete construction project.