Investigation in the Influencing Factors of Reinforcement Arrangement of Capital Targeted at Reinforcement Contractors in Kanto Region Part 1 : Cover Depth, Clearance and Contact of Reinforcement

This study presents a questionnaire survey of reinforcement contractors in Kanto region to identify factors affecting capital reinforcement arrangement. The results indicate that when reinforcement is placed strictly according to design drawings, insufficient cover depth, inadequate clearance between main rebars and interference between column and beam main rebars frequently occur. These issues are influenced by multiple structural parameters, including column and beam width, the designation, number, and spacing of main rebars, and the configuration of column–beam joints. Consequently, many projects require design revisions or rebar position adjustments during both design and construction stages.