地铁车站T型楼梯无柱化分析与研究

Column-free T type Staircase Analysis in Metro Station

针对地铁车站站厅层与站台层之间车站中部设置的T型楼梯的通用做法及车站站台中心空间被楼梯梯柱过度分割情况,通过钢筋混凝土板拱桥受力理论及计算方法,对取消梯柱后的T型楼梯下部梯段采用折板拱及圆弧拱形结构,利用MIDAS/Gen有限元计算软件,对无柱化楼梯结构进行计算并与现行方案进行比较分析,分析研究表明:T型楼梯取消下部梯柱,下部梯段按200 mm^400 mm板拱结构计算能够满足楼梯受力变形及抗震要求;对于无柱T型楼梯板拱结构梯板结构高度相对较小,有利于美观及楼梯下部视觉通畅、人员通行。以期对现行地铁车站T型楼梯设计提供借鉴及思考。

According to the common practice of setting the T type stair between hall layer and the platform layer of the subway station and the issue that central space of the platform has had to be segmented excessively by the columns of the T type stair,a column-free T structure stair has been introduced in this paper,where folding plate arch and circular arc arch structures are adopted in the lower part of the T type stair to replace the column structure.Based on the force theory and calculation method of the reinforced concrete slab arch bridge,a comparison between the existing structure and the new structure has been made with the analysis from Midas/GEN,and conclusions are as follows： 1） The column-free staircase could meet the force and deformation requirements when the arch type are200 mm - 400 mm; 2） The height of the stair can be shortened because of the non-column board arch structure,which could greatly contribute to a better appearance and a smoother crowd flow under through the stair. This paper could provide reference and suggestion for the future design of T type staircase in the subway station.