Residual Seismic Capacity of Reinforced Concrete Beam-Column Moment-resisting Frames Damaged with Joint-hinging Failure

2021 Fiscal Year Final Research Report

• Project/Area Number: 19H02284
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 23010:Building structures and materials-related
• Research Institution: Nagoya Institute of Technology
• Principal Investigator: Kusuhara Fumio 名古屋工業大学, 工学(系)研究科(研究院), 教授 (50361522)
• Co-Investigator(Kenkyū-buntansha): 岸田 慎司 芝浦工業大学, 建築学部, 教授 (10322348) ; 高橋 典之 東北大学, 工学研究科, 准教授 (60401270)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 鉄筋コンクリート / 柱梁接合部 / 接合部降伏 / 損傷度 / 耐震性能低減係数 / 残存耐震性能

Outline of Final Research Achievements

The test results of specimens of RC interior and exterior beam-column joints those were damaged with joint-hinging failure by preliminarily loading indicate that 1) restoring force, stiffness, and energy dissipation deteriorate significantly due to the preliminary damages in the range of experienced deformation, and 2) the damages do not affect the restoring force characteristics in the range of deformation that has not been experienced and limit deformation. In addition, damage classes for RC beam-column joints based on damage on reinforcing bars and concrete such as cracking, yielding, and crushing are defined.
In the seismic response analysis of RC frames where the beam-column joint is damaged, (1) response deformation of frames does not increase significantly compared to the beam-hinging type frame if the ratio of joint-hinging columns in the story is 40% or less, and (2) the ductility index for the beam-beam joint is about 1.5 to 4.

Free Research Field

建築構造

Academic Significance and Societal Importance of the Research Achievements

鉄筋コンクリート骨組の柱梁接合部に生じたひび割れなどの損傷の程度を表す損傷度を定義した。また，損傷度と柱梁接合部の残存耐震性能の関係，柱梁接合部の損傷の程度と骨組としての耐震性能の低下の関係に関する知見を得ることによって，地震により柱梁接合部が損傷した場合の鉄筋コンクリート造の建物の安全性を把握する手法を導くことができるようになった。