Abstract: A confined capping system provides a simple approach for compressive strength testing of high performance concrete specimens. The test specimen ends are capped with a conventional capping compound confined in steel rings larger in diameter than the specimen. The capped rings are compression tested in a conventional way. This method thus employs standard concrete laboratory testing equipment. An inexpensive customized capping apparatus may be used for preparing the specimen ends. The method ensures that confinement is provided to the cap without having to place tight controls on specimen end roughness prior to capping and on the cap thickness itself.