I'm just a fellow homeowner, but knowing that a standard concrete driveway is 4-5 inches and you're talking about an extra heavy load, I wouldn't be optimistic.

Better might be to bridge over the walkway. One way would be by using perhaps 6 inch dirt/rock berms on either side and placing down the kind of steel plates used in road construction to cover excavations at the end of the day. These seem to be strong enough for truck crossings and don't seem to flex much. You can probably find out how much they flex and then have the workers make ramps up to berms that are high enough that the steel plate will remain above the walkway.

There are probably other ways too, I'm not sure wood boards would be enough to spread out the weight. Steel beams, maybe so.

Sounds like whoever was scheduling the work tasks did the walkway too soon.

We drove a 34,000 lb boom lift across a sidewalk and it cracked it to kingdom come. (The sidewalk was already slated for replacement.) It sank so badly we had to put 2x12's under the machine, it was crushing the old concrete into the earth.

Casey

I can have someone with a large Excavator come in and place the rock I was just trying to Get the job done with the equipment I have on site. I had not planned to have a Boulder in this bed an poured the walk with a patio pour in the Fall. over the winter I discovered that snow slides off the standing seem roof so the boulder is a solution to a gap in the landscape plants.

put the boulder on round logs. either use them as skids and drag across or if you have enough of them you can roll the boulder across them. that way the sidewalk only has to support the weight of one entity (skid steer or boulder) at a time.

Satrom Design, hopefully in the 5 years since the question was asked they have come up with a solution.

its been 7 years I need to know what happened did you murder the slab?