Measured by loading a cylinder in a testing machine until it fails and dividing the peak load by the cross-section area, reported in psi or MPa. Residential slabs and footings commonly run 2,500 to 3,000 psi, commercial slabs and walls 4,000 to 5,000 psi, and high-rise columns 8,000 psi and up. Concrete is roughly ten times stronger in compression than in tension, which is why steel carries the tension.
Compressive strength on the podium field cures came in at 3,200, so the PT guys can stress tomorrow.
Also heard as
- strength
- comp strength
Related terms
f'c
Symbol for specified compressive strength, the design strength the engineer requires, usually at 28 days.
Cylinder
A cast concrete test specimen, usually 4 by 8 in or 6 by 12 in, crushed to measure compressive strength.
Break
A cylinder strength test result, or the crushing of cylinders in the lab.
Core
A cylinder of hardened concrete drilled out of a structure to test its strength or inspect its condition.
Flexural strength
The bending strength of plain concrete, measured by breaking an unreinforced beam and used for pavement design.