About 6 months ago a contractor poured a concrete slab to serve as a porch. The slab rests directly on the ground and measures 25' by 4' and is 4" thick.
The slab has remesh under it, no gravel, but the area was poorly prepared as evidenced by the edges of the pad where dirt was piled up and it sounds hollow under one corner when you stomp on it. Additionally, the contractor didn't saw any expansion joints.
A 4' hairline crack has appeared that bisects the pad roughly in the middle. Additionally this crack is right in the area of the entrance to the business.
I'm concerned that the crack will continue to grow as it freezes and thaws and that the pad will continue to degrade.
Should I be concerned about this crack?