Where can I get concrete cylinders strength-tested (ASTM C39)?
ASTM C39 breaks molded concrete cylinders in compression. Most construction materials laboratories run it; what differs is curing handling, break-age scheduling and whether the lab holds the accreditation your project specification names.
What the method covers
Molded cylinders cast and cured per ASTM C31 (field) or C192 (lab). Results describe the specimen as cast and cured, not the in-place structure.
Applicability caveats
- Poor field curing or transport damage lowers results — the test cannot correct for it.
- In-place strength questions need cores (ASTM C42), not more cylinders.
- Acceptance criteria come from your project specification or building code, not from C39 itself.