Uncoupled evaluation of the structural damage induced by tunnelling

Abstract

This paper illustrates an approximate procedure for the evaluation of the damage induced on existing buildings by the excavation of a tunnel. The method hinges on the development of a simplified structural model of the building, that can be readily incorporated into the finite-element mesh used to simulate the excavation of a tunnel. A first part of the article is devoted to the description of the equivalent structure and to the illustration of an identification procedure for the evaluation of its mechanical properties, based on appropriate scaling of the areal and inertial characteristics of the parent building. Then, the practical use of the method is illustrated by carrying out a series of three-dimensional numerical analyses of the excavation of an EPB tunnel, that include either the simplified or the fully detailed structural model of a masonry building. Using the results obtained with the complete building as a reference, it is shown that the simplified formulation is quite effective in capturing the main features of the soil-structure interaction for the problem at hand. Cases in which the method is less successful are discussed as well, indicating a suitable adjustment of the identification procedure for the simplified structural model

Finite-element modelling for the assessment of tunnel-induced damage to a masonry building

“…To ensure that the overall loading on the foundation is representative of a real building, allowance is made (by using an artificially increased unit weight for the masonry) for the weight of the roof, floors, windows, internal plaster and internal fixtures and fittings. In the current analysis, following Losacco et al (2014), the unit weight of the masonry is set to 23.75 kN/m 3 , i.e. an uplift of 25% on the actual unit weight.…”

Role of Footing Embedment on Tunnel–Foundation Interaction

“…However, in reality, shallow foundations are usually buried at a certain depth. This aspect has been discussed for foundations 1 Xu, May 13, 2021 that are continuous in the direction transverse to the tunnel by Losacco et al (2014); Yiu et al (2017) and Boldini et al (2018), however there is a lack of information for separate footings, for which embedment is arguably more important because of the potential for significant horizontal foundation displacements.…”

Continuum solutions for tunnel–building interaction and a modified framework for deformation prediction

“…Tunnelling-induced structure deformations depend on ground movements, structure stiffness, load condition, and structural configuration (both foundation and superstructure). In particular, the role of structure characteristics in tunnel-structure interaction (TSI) has been primarily investigated with numerical modelling and field data (Bilotta et al, 2017;Dimmock & Mair, 2008;Farrell et al, 2014;Franzius et al, 2006;Giardina et al, 2015;Fargnoli et al, 2015;Losacco et al, 2014;Mair, 2013;Pickhaver et al, 2010), although centrifuge tests of TSI have also been performed (Farrell et al, 2014;Ritter et al, 2017a,b;Taylor & Grant, 1998;Taylor & Yip, 2001). This paper aims to illustrate, through comparison with centrifuge data, the efficiency of simple continuum solutions in predicting the tunnelling-induced deformations of low-rise bearing wall structures on strip foundations.…”