Abstract
A high-pressure triaxial test is conducted on cement paste to understand the mechanism of mechanical performance of concrete under high confining pressure. The obtained deviatoric stress-mean strain relationship demonstrated that the cement paste is independent of confining pressure during ductile deformation with confining pressure greater than 30MPa. The ion-milled surface of the sample inside is observed with SEM, and the obtained contrast of the reflected electron image become darker after the test. This darker contrast is considered to be due to the deformation of hydrates at an atomic level such as crystal plasticity. Furthermore, the pore volume of the sample tested with 400MPa was drastically reduced compared with that of an intact sample.
