平面凹凸不规则高层结构弱连接楼盖在水平地震作用下的内力分析方法

Internal force analysis method for weakly connected diaphragm of high⁃rise structure with concave convex irregular plane under horizontal earthquake action

现行规范对平面凹凸不规则结构的“弱连接楼盖”的内力分析方法尚无相关规定,采用不同计算方法进行水平地震作用下的内力计算,往往得出相差颇大的计算结果。阐述了单肢端截面受力机理,将两个简化计算公式与弹性有限元法进行分析比较,并通过实际案例提出相应的设计建议。结果表明:两个简化计算公式假定物理概念明确,且计算简单,但是忽略了单肢上、下竖向构件剪力对单肢端截面内力的影响,与结构实际情况不符;忽略了结构扭转和结构竖向构件剪力差的抗剪作用。建议与弹性有限元法计算结果进行全面分析比较后,对简化计算公式在不同楼层部位提出适当的修正系数,使其可直接应用于设计。

The internal force analysis method of"weakly connected diaphragm"with concave convex irregular plane structure has not been prescribed in the current code.Different calculation methods are used to calculate the internal force under horizontal earthquake action,and often the calculation results are quite different.The mechanical behavior of the weakly connected diaphragm was described,the two simplified formulas were compared with elastic finite element method,and the corresponding design suggestions were put forward through practical cases.The results show that the two simplified formulas assume a clear physical concept and simple calculation,but ignore the influence of the shear force of the upper and lower vertical members of the wing on the internal force,which is inconsistent with the actual situation of the structure.The shear effects of structural torsion and shear difference of structural vertical members are ignored.After comprehensive analysis and comparison with the results of elastic finite element method,appropriate correction coefficients are proposed for different floor parts of the simplified calculation formula,so that it can be directly applied to design.