In this research, the effect of sub-system on model response for mechanized tunneling process has been taken into consideration. The main aim of this study is to modify the constitutive parameters in a way that the best agreement between numerical results and measurements is obtained. The sub-system includes supporting pressure at the face of the TBM, contraction along the TBM-shield and grouting pressure in the annular gap. The commercially available finite element code, PLAXIS is adopted to simulate the construction process. The soil behavior during the excavation is numerically reproduced by utilizing Hardening Soil model with small strain stiffness (HSsmall). The constitutive parameters are obtained via sensitivity and back analyses while they have been calibrated based on the real measurement of Western Scheldt tunnel in the Netherlands. Both local and global sensitivity analyses are used to distinguish which parameters are most influencing the soil deformation. Thereafter, the model validation is accomplished by applying different scenarios for face pressure distributions with respect to the slope of the tunnel. In addition, the effect of contraction factor is modified individually or coupled with the variation of grouting pressure. Evaluating the influence of the sub-system is conducted to assess its effects on the model responses and to seek the possibility to decrease the disagreement between the calculated displacement and real measured data.
[1]
Tom Schanz,et al.
Identification of obstacles ahead of tunnel face applying inverse approach
,
2009
.
[2]
Tom Schanz,et al.
Soil-Model Parameters Identification via Back Analysis for Numerical Simulation of Shield Tunneling
,
2013
.
[3]
Pieter A. Vermeer,et al.
Small‐strain stiffness in geotechnical analyses
,
2009
.
[4]
Tom Schanz,et al.
Global sensitivity analysis for subsoil parameter estimation in mechanized tunneling
,
2014
.
[5]
Adam Bezuijen,et al.
Processes around a TBM
,
2008
.
[6]
James Kennedy,et al.
Particle swarm optimization
,
2002,
Proceedings of ICNN'95 - International Conference on Neural Networks.
[7]
Tom Schanz,et al.
Sensitivity analysis of the model response in mechanized tunneling simulation – A case study assessment
,
2014
.