Inspection process
Slump test
Also called: concrete slump test, slump
A slump test measures the consistency of fresh concrete at the point of placement. A standard cone is filled and rodded in lifts, lifted off, and the amount the concrete settles is measured — that drop is the slump. It's a quick field check that the delivered mix has the right workability and hasn't been over-watered, which would weaken the cured concrete. It runs before the truck discharges, so bad concrete can be rejected before it's in the forms.
Why it matters
Water added on site to make concrete easier to place is the classic way to quietly cut its strength. The slump test is the gate that catches a mix that's too wet before it goes into the pour — once it's placed and cured, the lost strength is permanent and expensive to prove and fix.
How it shows up on site
The test is run at the pre-pour hold point along with sampling cylinders for strength testing, and a slump outside the specified range is grounds to reject the load. Results are recorded per truck; in RTI the slump reading and the cylinder set attach to the pour step, so the pour can't be marked placed without the fresh-concrete tests on record.
Standards it's verified against
Checklists that put slump test to work
Free, field-ready checklists, each with the photo every item needs before it can be submitted.
Related terms
- Hold pointA stop in the inspection and test plan where work cannot continue until a required party inspects and signs off the release.
- Witness pointA step where a party is invited to observe the work, but the crew may proceed if that party doesn't attend within the agreed notice.
- Pre-cover inspectionThe last inspection of an assembly before it is concealed — drywall, insulation, backfill, or a slab pour that hides the work underneath.
- Acceptance criteriaThe stated, measurable conditions installed work has to meet before it can pass — the yardstick an inspection judges against.
- Definable feature of workA discrete, separately inspectable task or segment of work with its own start, finish, and acceptance criteria within the QC plan.
- Preparatory phase inspectionThe first of the three phases of control — a before-work review of submittals, materials, and criteria for a definable feature of work.
Knowing the term is step one. Proving it is the job.
RTI holds the submit button until every mandatory item is answered and the photos are attached, then chains the record so it can be proven untouched later.