对北京某地下人行通道出现的挠度大、残余变形大等问题进行了分析。原结构较大面积的严重渗水致使混凝土的耐久性能受损、钢筋严重锈蚀是问题产生的主要原因。针对这些原因 ,通过方案比较和优化 ,提出了经济实用的钢 混凝土组合结构加固方案 ,并对加固方案产生的效益进行了分析比较 The problem of large deflection and large residual deformation of a pedestrian passage in Beijing is analyzed. The serious water seepage caused by the large area of ​​the original structure causes the durability of the concrete to be damaged, and the serious corrosion of the steel bar is the main reason for the problem. In view of these reasons, through the comparison and optimization of the schemes, the economical and practical steel concrete composite structure reinforcement scheme is proposed, and the benefit of the reinforcement scheme is analyzed and compared