単軸圧縮応力を受けるコンファインドコンクリート内に配筋された圧縮軸筋の座屈におよぼす諸要因の影響 : コンファインドコンクリート内に配筋された圧縮軸筋の座屈に関する研究(その1)

抄録

This paper describes effects of factors on strains at buckling of longitudinal reinforcement within confined concrete subjected to uniaxial compression. Experimental variables employed in this study were ratios of lateral reinforcement pitches to specimen diameters (S/D), an index of confining stress (Psσsy), yield strength of the lateral reinforcement (σsy), compressive strength of plain concrete (Fo), and shapes of the lateral reinforcement. Test specimens were cylindrical specimens with 200mm diameter and prismatic specimens with sections of 200 × 200mm, both of which were 600mm in height and without cover. The following conclusions can be obtained mainly. 1) Clear definition on strains at buckling of longitudinal reinforcement are proposed on the basis of axial force decrease of longitudinal reinforcement calculated from data of lateral deformation of the reinforcement. 2) Because buckling of longitudinal reinforcement is considered to depend on behavior of confined concrete, variables which make mechanical performance of confined concrete higher, such as smaller pitch and larger amount of lateral reinforcement, lower concrete strength, etc, increase the buckling strains.