PARAPHRASE ONLY

Discussion of Results

When a company wants to buy a proper concrete for their construction project, they should buy a concrete with a suitable strength for the construction so that no accidents happen in the future. There are two ways to estimate the strength of the concrete, and both of the ways were applied and tested in the experiment. The rst method is a non-destructive way to evaluate the strength of the concrete digitally without smashing it. First, by using a Schmidt hammer either horizontally or vertically downward or upward, a plunger hits the surface and immediately shows on the screen the strength value. The procedure was repeated for ten times and then the average of rebound numbers is calculated to get the closest number to the real strength of the concrete which was 39.2MPa (for MegaPascal). As it is known that the higher the rebound number is the stronger the concrete is. As for the second way to nd the strength of the concrete is a destructive method by using several equipment. At the beginning, a Vernier caliper was used to calculate from a at surface at two di erent points of a sample which is a concrete cube the width, depth, and height, and then calculate the average of each one of them. Second, we nd the mass of the cube by using a digital balance which was 2.929 kg, hence, we found the density by using mathematical equations and converting the measurements to the needed units such as Density= Mass÷Volume (which is W×D×H). Then, we nd the

compression failure load by using the Compression machine that crushes the concrete completely at a speci c point and the number does not change which

was 320.6 kN (for kiloNewton). Last, the compressive strength of the cube can be calculated by an equation F÷A (Compression failure load÷ Area) where the

unit of it is MPa.

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Conclusion

To reach to our purpose of calculating the compressive strength of the concrete using di erent methods .We used the destructive and non-destructive methods. As what is mentioned in the previous pages, for the destructive method a compression machine was used, as for the non-destructive method the electronic Vernier caliper and the Schmidt hammer were used. Both of these methods were tested against a hardened concrete block.

After testing the rst method that we used “Non Destructive Tests (NDT) “we concluded that it has many advantages such as time saving, testing can be rehashed, and enables continuous checking of the execution of the structure. On the other hand, the one disadvantage was noticed is Strength properties are not measured speci cally. Hence, it needs adjustment.

In addition, after using the second method, we concluded the advantages and disadvantages of destructive testing. The advantage of the destructive testing is that it allows us to test di erent mix designs to accomplish required strength. In the opposite side, the rst disadvantage of this testing is that it is costly, time consuming, and specimen do not actually represent actual structures.