框架结构侧移曲线的泛函推导和目标位移确定

Functional deduction of lateral displacement curve of frame structure and determination method of target lateral displacement

直接基于位移的抗震设计方法要求在设计之初确定结构各楼面处的目标侧移以便将多自由度体系转化为单自由度。基于Hamilton原理,从能量的理论出发建立了关于框架结构侧移曲线的泛函,通过数学中的变分原理推导了该侧移曲线,并指出了数学原理与力学中能量观点的联系,使得框架结构侧移曲线有了可靠的数学理论基础。最后提出了按该侧移曲线确定结构目标侧移的方法并通过算例说明了该方法的可行性。文中提出的侧移曲线适用于刚度沿高度分布较均匀的框架结构。

In direct displacement-based seismic design of buildings,the target lateral displacement on storys should be determined at first to transform MDF into SDF.According to the Hamilton principle,the functional about lateral displacement curve has been established from potential energy.The curve is deduced with variation calculus and energy opinions in mechanics,which are confirmed with math theory,through which the reliable theoretical basis of the lateral displacement curve of a frame structure is given.At last,determination method of target lateral displacement is suggested and the practicability of the method is shown through an example.The lateral displacement curve proposed in this paper can be applied to frame structures with regular stiffness distribution along the height direction.