地铁暗挖车站成本优化合理埋深研究

优秀的地铁车站设计方案应在保障安全性的前提下提高经济性。在对青岛地铁6座暗挖车站土建成本工程数据统计分析和君峰路车站典型案例细致剖析的基础上,构建了上软下硬地层地铁暗挖车站建设成本数学分析模型,系统分析了不同软弱土层厚度地铁车站建设成本随埋深变化特征,深入探讨了上软下硬土岩组合地层地铁暗挖车站成本优化合理埋深问题。结果表明:车站主体开挖面从软硬土岩组合地层交界面过渡到下覆岩层,车站建设成本有一个突然下降的阶段;覆岩厚度是衡量地铁车站土建成本的有效指标;车站主体置于坚硬岩层中并满足围岩自稳要求的最小覆岩厚度时车站经济性最好,可将车站主体隧道围岩满足自稳要求最小覆岩厚度时的设计深度作为合理埋深。

Study on the Reasonable Buried Depth of Mined Metro Station Based on Cost Optimization

Excellent metro station design scheme should improve the economy on the premise of safety. Firstly, the mathematical model for construction cost of mined metro station is constructed, based on the statistic analysis of engineering data and the in-depth analysis of typical case of the construction cost of Qingdao mined metro station. Then, the construction cost of mined metro station varies with buries depth is system analyzed under different thickness of soft soil stratum. Finally, the reasonable buried depth of mined metro station based on the construction cost optimization is discussed in the combined stratum of upper-soil and lower-rock stratum. The results show that the construction cost decreases suddenly when the excavation surface of the metro station main body transits from the combined stratum to the hard rock stratum; the cover layer rock thickness is the effective indicator for measuring the metro station construction cost; the metro station cost efficiency is optimal when the main body is placed in the rock stratum and kept the reasonable smallest thickness; the design depth which satisfies the minimum overburden thickness of the main body of the station can be taken as the reasonable burial depth.