Within the before picture of the cracked steps, you will see on the right-hand side the pulling apart from the walkway and the step. Cracked concrete happens when part of a concrete slab breaks and sinks into underlying soil that has compressed or washed away. These cracks aren’t just unsightly; they offer moisture a way to seep beneath the slab. This can cause the underlying soil to soften or even wash away completely. That in turn can cause the slab to crack further as it sinks into the void left by the washed-away soil.