新管幕结构受力模式及关键技术分析

沈阳地铁九号线奥体中心站采用Steel Tube Slab管幕工法建造覆土超浅埋暗挖地铁车站.对新管幕结构的纵向和横向受力模式进行研究，阐述了管幕结构的作用机理，并对管幕结构的抗弯承载力和抗剪承载力计算理论进行讨论，给出了相应的计算公式.结合奥体中心的施工工况，对管幕结构的内力进行计算.随着右侧导洞贯通时，与左侧导洞相比较，跨中正弯矩增加8%，最大负弯矩减小17.8%.管幕结构沿纵向跨中最大变形为6.46mm.研究结果对新管幕工法的应用和推广具有参考意义.

Analysis of Mechanical Characteristic and Key Technique of Steel Tube Slab Structure

Steel tube slab(STS)method is addopted to construct the ultra-shallow-buried subway station of the Aoti Central station， line 9 in Shenyang. The longitudinal and lateral mechanical characteristics of STS structure were investigated， and the interaction mechanism was elaborated; then， the calculation theory of bearing flexural capacity and shear capacity were discussed， and the relative formulas were presented. According to the construction condition， the internal force of STS structure during the construction was calculated. Compared with the left pilot tunnel， the positive mid-span bending moment of the supporting structure increases by 8% when the construction of right pilot tunnel is completed， and the maximum negative bending moment decreases by 17.8%. The maximum deformation of the longitudinal mid-span is 6.46mm. The results can provide some important references for the application and promotion of STS.