Yoshida Prize - Thesis

COMPRESSIVE FRACTURE BEHAVIOR AND MECHANICAL PROPERTIES OF RC COLUMNS WITH NORMAL-AND HIGH-STRENGTH MATERIALS UNDER CONCENTRIC COMPRESSION

RC columns made of concrete and steel from normal-strength up to high-strength were tested under concentric loading. The following variables were evaluated for their effects on the compressive fracture zone length and load-displacement relationship: tie arrangements, column length, concrete compressive strength, tie yield strength, and tie volumetric ratio. A formalized stress-strain model for confined concrete was developed, based on the test results in this study and our previous studies. Regardless of the gage length, tie arrangement and material strengths, it can be used more extensively than the previous models. The RC columns with high-strength materials subjected to cyclic loading were evaluated based on fiber analysis using the confinement mode. The analytical results were in good agreement to the experimental results.