I finally measured the slump on a wet load and couldn't believe the number

Had a pump truck show up last Tuesday for a 30 yard pour on a slab foundation. The mix looked way too wet coming off the chute so I grabbed my cone and rod. Did the test right there on the driveway. Slump came out at 7.5 inches. Spec called for 4. The dispatcher tried to tell me it was just the water from washing out the drum. Has anyone else had a ready mix plant fight you on a slump test like that?

2 comments

2 Comments

abby18926d ago

But isn't it possible the wash water really did throw off the reading? I've seen a drum that wasn't dumped properly add a surprising amount of water to the first few yards, enough to spike the slump before the load gets consistent. A 7.5 inch reading on a driveway test isn't ideal, but one test right off the chute might not tell the full story about the whole batch.

the_elizabeth26d ago

Had to be more than just wash water with a slump like that. They always try that excuse, like we just fell off the turnip truck yesterday.