衬砌刚度对盾构隧道抗震性能的影响分析

研究目的:提高盾构隧道的抗震性能是保证隧道安全运营、保证人民生命及财产安全的必然要求。盾构隧道抗震减震措施主要有改变衬砌一定范围内围岩的性能和改变结构本身的性能。改变衬砌结构本身性能方面有多种方式,如增加衬砌厚度,改变管片环向或纵向接头方式、改变衬砌刚度等。本文通过数值分析比较不同的衬砌刚度对盾构隧道抗震减震性能的影响,为盾构隧道抗震设计提供参考。研究结论:根据不同衬砌刚度盾构隧道的受力分析,得出单纯提高管片的刚度并不能提高盾构隧道的抗震性能,反而增加衬砌管片的受力。随着隧道衬砌刚度的增加,衬砌结构的位移减少量不足2 mm,因此增加衬砌刚度对约束盾构隧道在地震作用下的变形并不明显。

Analysis of Impact of Lining Rigidity on Seismic-resistant and Absorption Properties of Shield Tunnel

Research purposes: Improving the seismic performance of shield tunnel is to meet the certain demands of ensuring the safe operation of tunnel and safeguarding the people’s lives and properties.Changing the properties of the rock in a certain range of the lining and changing the structure performance are two main ideas on improving the seismic-resistant and absorption properties of the shield tunnel.There are many ways for changing the lining structure,such as increasing the lining thickness,changing the way of segment loop joint or vertical joint and changing the lining rigidity.In this paper,the numerical analysis and comparison of the impact of the different lining rigidities on the seismic-resistant and absorption properties of the shield tunnel for providing the reference to the design of seismic-resistant and absorption. Research conclusions:From the analysis of loading bearing of the different lining rigidities of the shield tunnel,it is concluded that only increasing the rigidity of the segment alone can not improve the seismic performance of shield tunnel,but increases the load on the segment.With the increase of the rigidity of the tunnel lining,the displacement of the lining structure is reduced by less than 2 mm,thus it is not obvious to restrain the deformation of the shield tunnel by increasing the lining rigidity under the effect of earthquake.