Aug 2020 DIY Concrete Reinforcement
Used in almost all large-scale civil engineering projects as well as domestic building projects such as foundations, lintels and loadbearing fittings, Sephaku Cement explains how to reinforce DIY concrete installations. Durable, low maintenance and made to stand the test of time, while concrete is one of the stronger building materials to use, when over exposed to the elements, incorrectly mixed and poured or placed under load-bearing or tensile pressure it can be vulnerable to cracks and compromised strength.
To follow, see Sephaku Cement’s Step by Step process on how to create your own DIY steel concrete reinforcements for home-based projects.
- Step One: Prepare your subgrade No matter what your DIY home improvement project may be, always be certain to spend an adequate amount of time preparing the subgrade on which you plan to place the concrete. Begin by clearing the surface and removing stones, rocks and any debris that may prevent a level pour. It’s also recommended that the surface is compacted and further smoothed out by making use of a tamping rammer, plate compactor, roller or hand tamper.
- Step Two: Partition the area and prepare the rebar Using timber boards to create the framework, demarcate the designated area that you will place the concrete. Once secured, using the framework as your template measure and place the steel rebar cutting it to the correct size to fit the frame. Be certain when measuring the rebar to leave around a 25mm to 50mm space between the outer frame and the rebar. Steel reinforcement should be used with a concrete strength of at least 25Mpa or more. The alkalinity of the cement will protect the steel from rust only if the compaction/vibration is sufficient to ensure complete bond between concrete and steel. Air voids and porous concrete will lead to rusting of the re-bar and subsequent detrimental cracking of the concrete. Once measured and cut to fit, remove the rebar from the timber framework and proceed to step three.
- Step Three: Mix and Place the Concrete Following the mixing instructions detailed on the bag of cement you are using, blend the concrete taking care to measure the correct ratios of water and aggregates required. Working quickly, you can begin to pour the wet concrete mix into the timber framework. At this stage you need only pour half of the mix, smoothing it across the full surface area. Once half full and smoothed over, place the measured steel rebar into place. Now pour the remaining half of the concrete on top of the rebar so that the steel reinforcement sits in the centre of the cast. Allow your reinforced concrete cast to adequately cure which could take between 24-48 hours. Once fully cured you can now remove the timber framework and proceed with the next steps of your project.
Steel concrete can also be reinforced following a similar process as the above, but instead of using steel rebar, you could also make use of steel rods, mesh, wires or cables to create your own DIY lintels, columns or decorative loadbearing concrete or reinforced retaining walls. Offering both bearing strength (increased load bearing capacity) as well as tensile strength, by combining concrete’s natural compressive strength with steel’s ability to resist tension reinforced concrete can be put to use in a number of applications that need added flexural and or tensile strength for durability.
One other exciting characteristics of steel concrete is steel’s propensity to expand and contract much to the same degree as concrete does when under the same type of influence from hot or cold conditions, what this means is that as concrete will expand and contract the steel used to reinforce the concrete will experience the same degree of growth or shrinkage, working hand in glove to maintain the structural integrity.