Too many concrete cracks are distroying the look of the flooring, especially outside, on the terraces and stairs. But, the good news are that this could be also fixed. Using a diamond blade on the circular saw, you need to make the crack wider and deeper. Take out the old concrete and clean the crack. Next, you need to fill the groove with new concrete. Smooth the surface with a rubber floor squeegee. The images are showing the steps and the link bellow is describing the process more deeply.

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