Coupled analysis of building damage due to tunnelling

Excavation works in urban areas require a preliminary risk damage assessment. In historical cities, the prediction of building response to settlements is necessary to reduce the risk of damage of the architectural heritage. The current method used to predict the building damage due to ground deformations is the Limiting Tensile Strain Method (LTSM). This method is based on an uncoupled soil-structure analysis, in which the building is modelled as an elastic beam subject to imposed greenfield settlements and the induced tensile strains are compared with a limit value for the material. This approach neglects many factors which play an important rule in the response of the structure to tunneling induced settlements. In this paper, the possibility to apply a settlement risk assessment derived from the seismic vulnerability approach is considered. The parameters that influence the structural response to settlements can be defined through numerical coupled analyses which take into account the nonlinear behaviour of masonry and the soil-structure interaction.

Statistical energy analysis of a built-up structure excited through its stiffening members

A new method of analysing high frequency vibrations in stiffened structures requires the calculation of a "power absorbing impedance matrix" for each plate in the system. The present paper is concerned with formulating this matrix by using point collocation in conjunction with basis functions representing incoming cylindrical waves. Key numerical issues are highlighted by considering the special case of a membrane, rather than a plate, and conclusions are made regarding the utility of the method.