结构刚度中心与质量中心偏差较大时,应考虑扭转的不利影响,将高层建筑结构等效为悬臂杆,从顶至底依次选取脱离体。根据位移协调条件,将结构的位移分解成平动与转动成分,得到相应的结构平动时构件所承担的剪力与结构转动时构件所承担的剪力。再根据力的平衡条件,推导出双向地震作用下考虑构件抗扭刚度时结构的线弹性扭转角,并对构件的剪力及变形进行了修正。算例表明,考虑构件抗扭刚度时结构的线弹性扭转角、构件的剪力与变形均减小。该方法概念清楚,符合工程实际。
The disadvantageous effect should be considered when the deflection between the structural mass center and stiffness center exists. The whole building can be equivalent to a cantilever bar, and the structural total displacements can be divided into parallel displacement and rotational displacement based on the harmonize condition of displacement, and the parallel shear and the rotational shear of the elements can be accordingly obtained by selecting the renegade body from top to bottom in turn. The structural linear- elasticity torsion anger considering the torsion stiffness of the elements can be detruded under the bidirectional earthquake action the harmonize condition of force, and the shear and displacement of the elements is corrected. It is shown that the structural torsion angers increase, the shear and the displacement of the elements decrease, and its conception is so clear that the result accord with engineering practice.