基于能力保护的新型拉压双向限位装置设计方法研究

Research on Design Method of a New tension-compression Bidirectional Restrainer Based on Philosophy of Capacity Protection

为保护通航渡槽结构缝之间止水不被破坏,提出替代止水受力的新型拉压双向限位装置.此装置力学特征类似销轴耳板连接结构,此类结构有多重破坏模式的弱点.为克服此弱点,结合《钢结构设计标准》(GB 50017—2017)中销轴耳板连接结构设计方法,在该装置的静力设计中,基于能力保护的设计思想提出了以单一销轴弯曲破坏为该装置破坏模式的设计方法.基于实体有限元数值模拟,分析了加载过程中此装置整体与各部件的受力-变形曲线特点.结果表明:以外荷载-整体变形量曲线不出现塑性特征为依据,判定装置的静力承载力大于设计外荷载、设计方法偏于安全;通过销轴的外荷载-弯曲变形量曲线与限位装置的外荷载-整体变形量曲线显现的非线性特征相一致以及板的外荷载-整体变形量曲线在加载过程中基本保持线性状态,说明板是被保护构件、装置破坏模式为单一的销轴弯曲破坏.研究结果表明此设计方法现实可行.

To resist the forces in stead of water-stop which is in structural joints between adjacent ducts of navigable aqueducts,a new tension-compression bidirectional restrainer with similar operation mechanism of pin-plate connection is proposed.To overcome the disadvantages of multiple failure modes with steel structure of pin-plate connection,a design method of the restrainer with the single failure mode of pin bending is suggested based on the specifications of pin-plate connection in Chinese code for steel structures design(GB 50017—2017)and philosophy of capacity protection design.The characteristics of force-deformation curves for the restrainer and its components are analyzed during loading using a finite element model.The results show that,based on the curve of external force and restrainer whole deformation,the static bearing capacity is greater than the designed external load,which means that the design method is safe.The external loadbending deformation curve of the pin-plate exhibits nonlinear consistency with the external load-deformation curve of the restrainer.The the curve of external load has a good agreement with the whole deformation of the restrainer.And the curve of the external load versus pin bending deformation shows almost linear state during the loading process.It means that the plates are protected members and the pin bending failure is the single failure mode of the restrainer.The results show that the proposed design method is realistic and feasible.