The physical test allows investigation of key elements of one domain whereas the numerical simulation efficiently accounts for the contribution of an adjoining domain. Hybrid testing consists of the implementation of the substructure approach ( Blakeborough et al., 2001) through the coupling of a physical model with a numerical simulation. The purpose of this paper is to present the development of a hybrid testing methodology that takes advantage of the relative strengths of physical modelling using a centrifuge (focusing on the geotechnical domain) and numerical modelling (focusing on the structural domain) such that an accurate analysis of a tunnel–soil–pile–building interaction scenario can be achieved. While it is virtually impossible to accurately replicate a complex structural system within a centrifuge test, numerical modelling of structural systems can give a very good replication of their behaviour. The application of a constant load to piles implies the assumption that the superstructure is infinitely flexible, which does not account for the realistic redistribution of loads through the connected superstructure. The use of an equivalent beam within physical modelling tests to replicate a complex structural system such as a concrete frame or masonry building is an over-simplification that can lead to inaccurate or misleading outcomes. However for physical modelling purposes, the structure is simplified as an equivalent beam or constant pile loads are applied. For example, for a building on a raft or piled foundation located above a newly constructed tunnel, numerical and analytical modelling has indicated that the characteristics of the structural system has an effect on the resulting ground and structural deformations ( Franza et al., 2017 Franzius et al., 2006 Giardina et al., 2015 Mirhabibi and Soroush, 2013 Mroueh and Shahrour, 2003 Potts and Addenbrooke, 1997). However, these experiments have all included simplified models of structural systems. In the area of tunnelling and tunnel–structure interaction, centrifuge modelling has enabled a better understanding of the parameters that control settlement trough shape ( Mair et al., 1993 Marshall et al., 2012) as well as the interactions between tunnelling-induced ground displacements and buried infrastructure or foundations ( Farrell et al., 2014 Franza and Marshall, 2018 Jacobsz et al., 2004 Marshall and Mair, 2011). The production of small-scale models which accurately simulate the real behaviour of these embedded/connected entities is often extremely challenging. One issue relates to the accurate modelling of the interactions between soils and buried or connected structural entities within centrifuge tests. However, there remain various limitations regarding the extent to which physical models can simulate real geotechnical systems.

Liang et al., 2014 Ritter et al., 2017) as well as provide high-quality measurements of material behaviour. Models are now routinely developed which give realistic representations of soil–structure interaction systems (e.g.

The complexity and level of sophistication of physical models tested within geotechnical centrifuges has developed considerably in recent years. Data are provided from preliminary tests which highlight the capabilities of the system to accurately model the tunnel–building interaction problem. A novel data-exchange method between Abaqus and LabView is presented, which provides a significant enhancement compared with similar hybrid test developments. The CCNM application can accommodate simple frame analyses as well as more rigorous and non-linear simulations using Abaqus. To appropriately model the full-scale scenario, a challenging force-controlled system was developed (the first of its kind for hybrid testing in a geotechnical centrifuge). The methodology takes advantage of the relative merits of centrifuge tests (modelling soil behaviour and soil–pile interactions) and numerical simulations (modelling building deformations and load redistribution), with pile load and displacement data being passed in real time between the two model domains. In this paper, the development of a coupled centrifuge-numerical model (CCNM) pseudo-dynamic hybrid test for the study of tunnel–building interaction is presented. Hybrid testing offers the ability to combine capabilities from physical and numerical modelling to overcome some of the experimental limitations. buildings) generally cannot be replicated such that complex full-scale characteristics are obtained. Geotechnical centrifuge models necessarily involve simplifications compared to the full-scale scenario under investigation.

Mathscript node labview 2017