Budapesti Műszaki és Gazdaságtudományi EgyetemÉpítőmérnöki Kar - építőmérnök képzés 1782 óta

Tunneling-soil–structure interaction (TSSI), one of the most major subjects in the domain of earthquake engineering, has been paid comprehensive attention internationally in recent decades. TSSI phenomena concern the wave propagation in a coupled system: structures built on or in the soil surface.

 

The recent progresses in geo-materials constitutive modelling, as well as the development of advanced numerical codes based on finite element methods, allow to solve very complex boundary value problem, with an easy user interface. The goal of this research is to present a method that shows how 3D FEM codes are able to be a powerful tool for evaluate final settlements and for studying appropriate measures to avoid negative impacts due to the TBM-EPB excavation in urban area.

 

Two possible paths are illustrated in order to obtain reliable predictions of the induced settlements:

-the first is based on soil in-situ data with sensitivity analysis and back analyses and will be useful for preliminary stages of the tunnel design;

-the second is based on the soils and rocks laboratory test with post-predictions of the monitored sections and will be used for more reliable further predictions.

 

The experimental results are used to evaluate the numerical models. In particular, the comparison between experimental and numerical results is used to select the more adequate soil model, evaluate the need for using a no-tension interface between the soil and the structure and assess the model’s ability to simulate the structural response. These results can be useful for real time adjustment of the planned operational works.

 

In order to achieve the objectives of the thesis following steps will be taken into consideration:

 

Firstly, the choice of good constitutive model will be discussed and the most important geometrical and physical aspects of modeling will be investigated.

 

Secondly, two strategies for predicting the induced settlement will be proposed, one based on in situ data, sensitivity analysis and back analysis technique and one on laboratory tests. Finally, an extended constitutive model to describe mitigation measures will be presented and applied to real case.