Abstract The separated double-tube tunnel of the Xuanwumen station passes vertically beneath an existing station of the Beijing Metro Line 2. To ensure smooth construction, deformation of the existing station needs to be predicted properly. In order to do this, a displacement back-analysis is introduced, and a finite-element model for the dynamic simulation of the construction process is set up. Calculation parameters are determined based on the measured displacement in previous construction steps of the trial section, then the station deformation in the next construction step is predicted by back analysis. The method shows that: the back-analysis is more accurate than the direct analysis, with a maximum deformation error of 0~2.16mm and a maximum differential settlement error of 0.12~2.59mm; its prediction accuracy is influenced by the approaching construction method; and in a case where construction schemes for the previous and subsequent construction steps are similar, the prediction is more accurate.
Abstract：
The separated double-tube tunnel of the Xuanwumen station passes vertically beneath an existing station of the Beijing Metro Line 2. To ensure smooth construction, deformation of the existing station needs to be predicted properly. In order to do this, a displacement back-analysis is introduced, and a finite-element model for the dynamic simulation of the construction process is set up. Calculation parameters are determined based on the measured displacement in previous construction steps of the trial section, then the station deformation in the next construction step is predicted by back analysis. The method shows that: the back-analysis is more accurate than the direct analysis, with a maximum deformation error of 0~2.16mm and a maximum differential settlement error of 0.12~2.59mm; its prediction accuracy is influenced by the approaching construction method; and in a case where construction schemes for the previous and subsequent construction steps are similar, the prediction is more accurate.
WANG Jian-Chen,
ZHANG Ding-Li,
ZHANG Cheng-Ping etc
.Dynamic Back-Analysis and Prediction of Overlying Subway Station Displacement Induced by Approaching Excavation[J] MODERN TUNNELLING TECHNOLOGY, 2014,V51(4): 58-66
2014, Vol. 51 