Development of High Reliability Steel Structural System Using Structural Joints as Energy Dissipating Elements against Strong Earthquake

提出了一种螺栓连接钢结构体系，在结构节点施工工作的稳定质量保证和框架的抗震性能方面具有优势。宽翼缘梁和柱由高强度螺栓连接，采用屈曲约束膝撑阻尼器。为了实现该系统，进行了连接的基本测试。最后，对2层全尺寸无焊接结构框架进行了膝撑阻尼试验。所得结论总结如下：1)给出了膝关节支撑阻尼器的关节单元结构和屈曲抑制方法。根据提出的程序，设计和制作了用于加载试验的全尺寸试验连接。2)对该结构体系的全尺寸梁柱组件进行了加载试验。对节点单元的弹性刚度、结构的屈服极限和破坏极限等基本力学性能进行了试验研究。3)提出了采用膝撑阻尼系统有效抑制梁两端连接柱侧屈曲的方法，并对其有效性进行了实验验证。给出了约束梁屈曲的设计步骤。4)给出了系统刚度和强度的解析方法。通过地震反应分析，验证了简化方法的准确性。以某建筑结构设计为例，与普通抗弯矩框架的结构性能和造价进行了比较。6)通过实尺试验，证实了该结构体系具有良好的结构性能和变形能力。

A steel structural system with bolted connections are proposed to produce advantages on the steady quality assurance related to the construction work of the structural joints and the seismic resistance of the frames against strong earthquakes. Wide-flange beams and columns are connected by high strength bolts using buckling restrained knee brace dampers. In order to actualize this system, the basic tests of connections were conducted. Finally, 2 story full scale frame of weld-free structure with knee brace dampers were tested. Concluding remarks obtained are summarized as follows :1)The configuration of joint elements and the buckling restraining method for knee brace dampers are indicated. According to the proposed procedures, the full-scale experimental connections for loading tests are designed and fabricated.2)Loading tests for full-scale beam-column subassemblies of the proposed structural system are conducted. The fundamental mechanical properties, namely, the elastic stiffness of joint elements, the yield limit and the collapse limit of structures are experimentally inspected.3)The effective restraining method against the lateral buckling of a beam which is connected to the columns at the both ends by the knee brace damper system is suggested and its effectiveness are experimentally confirmed. The design procedures for the buckling restraining of the beam is indicated.4)The analytical method of the stiffness and the strength of the systems are indicated. Accuracy of the simplified method is confirmed through the earthquake response analysis.5)An example of a structural design for a building is shown and the structural performance and the cost for construction are compared with an ordinary moment resisting frame.6)From the full scale test, it is confirmed that the structural system has the high quality of structural performance and the deformation capacity.