AASHTO T 231-17 PDF Download

AASHTO T 231-17 is a standard practice that outlines the procedures and materials required for capping cylindrical concrete specimens. The purpose of this standard is to ensure uniformity and accuracy in the testing of concrete specimens by providing guidelines for capping.

The standard covers two different methods of capping, depending on whether the specimens are freshly molded or already hardened. For freshly molded concrete cylinders, a neat cement cap is used, while for hardened cylinders and drilled concrete cores, high-strength gypsum plaster or sulfur mortar is recommended.

The standard also addresses the importance of using appropriate apparatus, such as a capping plate and a capping compound mixer, to ensure the proper application of the cap. It specifies the requirements for the materials used in capping, including the composition and strength of the capping compound.