Effects of building three-dimensional modeling type on twin tunneling-induced ground settlement

• Interaction between twin tunnels and surface buildings is studied in this article.
• Four different types of 3D building models are simulated.
• Effects of different three-dimensional building modeling on tunnelling-induced ground settlements in FE simulations are studied.
• Full 3D model outcomes are compared with common practice 2D modeling of surface buildings (surface elastic beam models).

Buildings are usually modeled as elastic beams in plane strain finite element (FE) simulation of tunnel-building interaction. However, neither tunnel nor surface buildings behave in a plane strain manner. In order to assess the effect of building modeling type on twin tunneling-induced ground settlement, some full three-dimensional FE models were analyzed and the effect of building modeling type was reviewed. Two dimensional (2D) plane strain interaction and green-field situation models were also analyzed to compare the results with the three dimensional (3D) models and assess the influence of modeling type. Outcomes of the studies showed that three-dimensional modeling has great influence on the results and equivalent surface beam, which is used in common practice of two-dimensional plane strain models, over-estimates the stiffness of building and leads to less settlement prediction in comparison with 3D simulation.