This driveway was sinking in the middle from what we thought was a thin spot in the slab, but it turned out that there was poor sub-grade under it causing it to settle and eventually crack. Once the old driveway was removed, Evans Landscaping brought in new 304 sub grade that was heavily compacted. Moraine Materials provided the concrete; we use their “signature driveway mix” that contains fiber for added strength. Adding fiber helps prevent cracking and is a great alternative from rebar or wire mesh. None of the driveways we have replaced with this mix have cracked.