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Booming down on a 50 ton Grove in Akron last spring taught me I'd been setting my outrigger cribbing wrong for 5 years.
I always leveled off the blocking before the crane got there but never checked if the ground under it was actually solid until I felt the whole machine settle an extra inch on one side during a pick, anyone else skip the ground compaction step and learn the hard way?
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the_ben1mo ago
@susan brings up a good point about how you never really know what's under the first few inches. I read somewhere that old building foundations or buried debris can cause a soft spot even on ground that looks solid. That inch of settling I felt was enough to make me rethink everything.
@susan is right that plate compactors can only do so much, but I've started using a probe bar to check for voids before I even lay down cribbing. It takes an extra 10 minutes but beats having the whole rig shift on you. Ground prep is one of those things where you can't afford to guess, even if it feels like overkill sometimes.
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the_susan1mo ago
...and honestly I'm wondering if we're overthinking this. I've set cribbing on what I thought was solid ground plenty of times, and yeah sometimes you get a little settling. But an inch? That sounds like maybe the ground was bad to begin with, not that you skipped some special compaction step. I've seen guys spend hours with plate compactors and still hit a soft spot. At some point you're just guessing what's under the first few inches.
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