张  力          （北京市建筑设计研究院  100045）

[提要]  用力法进行对称型剪式楼梯的内力分析，并与空间梁系、有限元法模型进行了比较，证明将复杂的空间对称型剪式悬挑楼梯简化分解为正置和倒置的平面梯形刚架，采用力法求解内力，方法简便可靠，在此基础上进行了对称剪式楼梯的配筋设计。为提高支承楼梯的水平对称悬挑折梁的刚度，设计采用了后张预应力技术。
[关键词]  对称型剪式楼梯  正置刚架  倒置刚架  力法

Space girder structure, finite element method and force method are applied to analyze symmetrical type scissors stairs. The comparison of the results calculated by the three methods shows that the complicated space symmetrical type scissors stairs can be inverted to a ladder rigid frame. Because the stairs are simply supported on horizontal symmetrical overhanging folded beam, post-tensioned prestressed force technology is used to solve the effect of displacement and deformation of the beam.
Keywords:  symmetrical type scissors stairs; upside rigid frame; inverted rigid frame; force method