Elucidation of 3-D Dynamic Characteristics and Evaluation of Retained Seismic Safety of Loose-Hole type Roof Joints

2021 Fiscal Year Final Research Report

• Project/Area Number: 17K06632
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Building structures/Materials
• Research Institution: Chiba University
• Principal Investigator: Shimada Yuko 千葉大学, 大学院工学研究院, 准教授 (90586554)
• Project Period (FY): 2017-04-01 – 2022-03-31
• Keywords: 定着部 / せん断力伝達 / アンカーボルト破断 / ルーズホール / 水平二方向載荷

Outline of Final Research Achievements

The behavior of a loose-hole type roller bearing, which is often used in the bearing section of a vertical truss roof, was investigated by elemental experiments and finite element analysis simulating the specimen to determine how the bearing fails under seismic input from two directions and how the component elements are related to each other. The results show that when the maximum sliding velocity is less than 100 mm/s, the velocity dependence is weak; when the maximum velocity exceeds 100 mm/s, the frictional resistance decreases linearly with increasing velocity; when the base plate slides at an angle, the friction coefficient increases by about 0.1; and when the anchor bolts contact the sides of the base plate in the two-directional horizontal loading, the friction resistance increases by about 1.0. In the case of two-directional horizontal loading, the anchor bolts contacted the sides of the base plate, which then deformed and stopped sliding.

Free Research Field

鋼構造，合成構造，耐震工学

Academic Significance and Societal Importance of the Research Achievements

他のすべり支承より安価で簡単に施工でき，立体トラスを有する既存建物で一般的に用いられているルーズホール形式のローラー支承について，これまで検討がほとんどなされてこなかった水平二方向入力や動摩擦力の影響を含めた検討により，よりリアルな支承部の挙動と特徴を明らかにできた．本研究の成果は，即時に実務に直結できる内容であり，新築建物のみならず，既存建物に対して耐震補強を行う場合，更には被災した建物を復旧させる場合においても，ルーズホール設置型のローラー支承を安全かつ最大限に活用できるようになる面で，耐震工学に大きな貢献をもたらすものである．