分离式暗挖地铁车站结构断面型式正交优化设计

Orthogonal optimization design for cross section of separate metro station constructed by using shallow tunnelling method

本文以双洞分离式浅埋暗挖地铁车站为研究对象,采用正交试验设计方法,研究了不同的地铁车站结构断面选型影响因子对地表沉降、洞周收敛偏差值、围岩塑性区面积和应力集中等力学指标的影响规律,并分析了结构断面选型影响因子对开挖断面面积和衬砌周长等经济指标的影响规律,探讨了地铁车站结构断面形状及洞室布置参数、本构模型参数和支护参数等11项因子对各项试验指标的影响程度。基于对各项试验指标的影响程度,确定了影响该指标因子的主次顺序,并根据综合平衡法直观分析,获得了双洞分离式暗挖地铁车站结构断面型式的最优因子水平组合。

By taking separate metro station constructed by shallow tunnelling method as research object, a series of orthogonal tests were carried out to investigate the influence rules of impact factors for cross section selection on mechanics indexes, such as ground surface settlement, deviation of displacement convergence, plastic zone size of surrounding rock and stress concentration. Moreover, the influence rules of impact factors for cross section selection on economic indexes, such as excavation area and lining circumference, were also analyzed. Furthermore, the influence degree of 11 factors(including parameters of cross section shape and station layout, constitutive model parameters, support parameters, etc.) to the different test indexes was discussed in detail. Based on integrated balance method, the best cross section parameters for separate metro station constructed by shallow tunnelling method was obtained.