Researches into the complete stress-strain curve for concrete

This paper describes two series of tests on concrete specimens for the purpose of determining the complete stress-strain relation in uniaxial compression, including the falling branch. In the second series, lateral as well as longitudinal strains were measured which showed that initial tension cracking occurs locally within the gauge length and that portions of this length may be uncracked at maximum load on the specimen. The results included in the paper demonstrate the ability of concrete to undergo very large changes in length without ceasing to carry load.