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The soil-structure interaction (SSI) effects can substantially alter the behaviour of structures during earthquakes. Implementation of SSI within the seismic analysis often leads to lower stresses in the structure and therefore a more economical design. The recently introduced provisions in European and American codes allow for this type of approach. However, consideration of SSI can also lead to the observation of unfavourable effects (undetectable in a fixed-base analysis) due to the modification of the structure’s dynamic properties. Examples of unfavourable effects include higher global displacements or story drifts, increases of the base or story shear forces, higher post-elastic demands in the structural members or the collision of adjacent buildings separated by an insufficient structural joint. These unfavourable effects can be related to various parameters such as the structural system (frames or shear walls), foundation type (shallow or piles), geometry of the foundation, height of the building, soil type, seismic input, presence of adjacent buildings, etc. Under these circumstances, the integration of SSI into the current structural design becomes essential. As the mathematical formulation of the phenomenon is very complex and involves many parameters, the definition of complete numerical models is difficult. The provisions in the codes are often general and do not give the practicing engineers clear modelling solutions. An analysis of the current situation in the field of SSI is carried out, with a focus on the design of reinforced concrete structures. Based on an extensive literature review, the unfavourable seismic effects and the main parameters that determine them are identified. Conclusions are drawn regarding the situations when SSI should be mandatory and on the different possibilities of implementing SSI in the structural design.

The paper proposes a numerical model to estimate the structural behaviour of a stickbuilt glazed curtain wall system subjected to an imposed displacement of the supports in the plane of the wall. We discuss the role of the parameters that influence on the maximum inter-storey drift corresponding to the service limit state of the wall. The considered parameters are the dimensions of the glazed panel, the gap between the panel and the aluminium frame and the gap between the supports and the mullions. We discuss the problem of remnant deformation of glazed panels, and of misalignment as serviceability criteria. Comparisons are made to laboratory testing results.

The current state of testing methods for assessing the mechanical properties of old masonry buildings is reviewed, with a focus on the methods adapted for heritage structures. For these buildings, an accurate assessment is needed in order to minimise the interventions extent while ensuring an adequate structural safety level. As old masonries are non-homogenous and exhibit a highly anisotropic behaviour, numerous parameters are required for correctly simulating the behaviour under a given load scenario. In earthquake-prone areas, numerous failure patterns, in-plane and out-of-plane, can occur for the structural walls, each of them depending on different characteristics of the material. If for new masonries the testing procedures are standardised, for old buildings less standardised tests exist, while investigations are often based on modified or empiric methods. The testing methods can be classified as destructive, minor destructive and non-destructive. The destructive methods are the most precise but are extremely intrusive and may not be acceptable for heritage listed buildings. The non-destructive methods mostly provide qualitative results. The minor-destructive tests are often the most adapted for the study of historical buildings, as they can provide relevant information while affecting only in a limited extent the existing elements.

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