【摘要】 选取藏式古建筑中普遍存在的一类节点进行分析。引入空间弹簧单元,得到藏式古建筑梁柱节点连接的简化模型;并将表达空间弹簧单元的刚度矩阵的参数简化为转动刚度参数K1和拉压刚度参数K2,采用荷载位移法和多级串联弹簧模型确定K1和K2的参考值。以典型藏式建筑结构模型为算例,分别探讨两个刚度参数对结构自振特性的影响。结果表明:转动刚度改变对结构自振频率影响不大,动力分析时可将之视为刚性连接;而轴向拉压刚度改变对结构低阶自振频率影响明显,动力分析中有必要考虑雀替的竖向弹簧作用。更多还原

【Abstract】 A type of connection widely exists in ancient Tibetan buildings is analyzed.Based on 3-D spring elements,a simplified FEM model of beam-column connection of Tibetan ancient building is obtained.It is assumed that the matrix parameters of the spring element can be described only by two stiffness named rotational stiffness K1and axial stiffness K2.The values of K1 and K2 are respectively calculated according to load-displacement curve and series spring model.An element model of typical structure frame is established,and effects of the two kinds of stiffness on natural vibration characteristics of structure are analyzed.Result shows that:the change of rotational stiffness has little effect on natural frequency of structure,and it can be seen as infinity in dynamic analysis of structure.However,the change of axial stiffness has obvious effect on natural frequency of structure,and it should be considered as a semi-rigid spring in dynamic analysis of structure.更多还原