Stafford -- To repair this staircase we used our three-part Concrete Protection Services. First, we inject our PolyLevel foam underneath the concrete to lift, level, and stabilize the stairs with the landing. Second, we fill in the joints using out NexusPro to protect the ground underneath from further settlement. Lastly, we use our SealantPro to seal and protect the concrete from further oil, water, and salt stains. Great work!