框架参与箱基共同工作时等效刚度的衰减规律

Attenuation Law of the Equivalent Stiffness of Frame Superstructure Interacted With Box Foundation

基于框架结构、箱基和地基土三者共同工作的空间受力体系，用能量法建立了上部框架结构参与箱基共同工作时等效刚度的通用计算模型．并根据势能等效的原则提出了“比例矩阵法”，推导了反映上部结构各层刚度在共同工作体系中发挥作用大小的刚度贡献系数解析表达式．揭示了上部框架结构某层的刚度贡献值随着层位的升高而衰减的若干基本规律．

Based on the spatial structure system composed of frame,box foundation,andsoil under interaction,a general-purpose model for calculating the equivalant stiffness of theframe superstructure is established by using the energy method.A“propotional matrix”method is presented auording to equivalence of potential energy. An analytical formulae ofcontribution factor is derived indicating the partion of the stiffness which each story of theframe stracture contributes to the interaction.Some foudamental laws of stiffness contribu-tion attenuation if brought to light as follows:the stiffness contr,bution of a certain story inthe frame attenuates with the storey number increasing.