基于反应位移法的地铁盾构隧道抗震设计

Aseismic design of metro shield tunnel based on the displacement response method

目前地铁隧道常采用盾构法施工,为研究地震作用对盾构隧道的影响,文章首先分析盾构隧道的抗震性能目标,其次提出基于直径变形率的盾构隧道在性能要求Ⅰ时的变形限值,最后采用手算及midas-civil软件进行反应位移法抗震分析。分析表明,手算结果与软件计算结果接近,在E2地震作用下,盾构隧道承载力满足规范要求,变形满足性能要求Ⅰ,即中震弹性。

Metro tunnels are frequently constructed by using the shield method.In order to study the impact of seismic action on shield tunnels,the seismic performance objectives of shield tunnels were analyzed.Subsequently,the deformation limit of shield tunnels,based on the diameter deformation rate,was proposed in accordance with performance requirements I.Manual calculations and Midas-Civil software were then used for aseismic analysis using the displacement response method.The analysis showed that the results of manual calculations were close to those of software calculations.Under the action of E2 seismic loads,the bearing capacity of the shield tunnel met the requirements of associated codes,and the deformation met the performance requirements I,that indicating the elasticity under moderate seismic met associated codes.