Cylinder break
The lab test in which a concrete cylinder is crushed in a press to determine compressive strength. The reported number is the failure load divided by the cylinder's area.
What does cylinder break mean?
Break results come with a fracture pattern that technicians record, because unusual patterns can indicate a poorly capped or damaged specimen rather than weak concrete. A single low break does not condemn a placement, since acceptance criteria are based on averages. Investigating a low result usually starts with how the cylinder was made and cured, not with the mix.
In practice
A low break triggers a familiar sequence: pull the batch ticket, check the field cure conditions, then consider coring the actual structure.