地铁车站顶板上翻梁结构设计优化

为了解决地铁车站顶板上翻梁构造引起的上方基坑回填施工困难和管线覆土厚度不足等问题，对地铁车站顶板结构设计进行优化。在充分利用地铁车站结构空间效应和组合梁结构优势的基础上，结合顶板构造特点和施工工艺要求，采用H型钢混凝土组合梁代替传统钢筋混凝土梁，并进行了承载能力和正常使用极限状态验算。结构设计优化结果表明，在降低梁高的前提下，采用组合梁方案既可以提高梁-柱节点的整体性，改善顶板的抗裂性，也为改善车站基坑回填施工条件、提高施工质量创造有利条件。

Structural design optimization of inverted T-shaped beam in stop floor of metrostations

In order to solve the problems in the backfilling of the upper foundation pit and insufficient thickness of covering soil for the pipelines, which were caused by the construction of the inverted T-shaped beam on the metro station roof, the structural design of metro station roof was optimized.On the basis of making full use of the spatial effect of metro station structure and the advantages of composite beam structure, combined with the characteristics of roof structure and construction process requirements, the H-shaped steel reinforced concrete composite beam was used to replace the traditional reinforced concrete beam, and the ultimate limit states as well as the serviceability limit states were checked. Results of structural design optimization show that, on the premise of reducing the beam height, using the composite beam scheme can not only improve the integrity of beam-column joints and the crack resistance of the roof, but also create favorable conditions for improving the backfill construction conditions of the station foundation pit and improving the construction quality.