Weak Soil Deposits and their Influence in Structural Stability of Buildings. Observations on Durres from the 26 November 2019 M 6.4 Albanian Earthquake

This paper is based on the visual observations of the authors during two site visits in Durres area, 3 (three) and 10 (ten) days after the earthquake. By the time, these visits were made to the most severely damaged buildings that hadn’t been evaluated yet. The seismic hazard in Albania and profound relevance of geotechnical earthquake engineering were demonstrated by the 26 November 2019 M 6.4 Earthquake Sequence. Durres was hit hard by a series of strong earthquakes in the vicinity or within the city boundaries. Many buildings in Durres were on shallow foundations and some of these were badly affected by liquefaction including excessive settlements and tilting. The geotechnical performance of the site, including issues of soil liquefaction, cyclic softening, lateral spreading and stability during shaking may have a significant effect on the performance of building foundations (or even dominate performance in the case of soil liquefaction and lateral spreading) and must be carefully considered prior to selecting a suitable foundation type or commencing foundation design. Soil conditions in a construction site affect the magnitude of the earthquake intensity. Soft soils amplify oscillations coming from the base rock and extend the period of oscillations felt by a building. Earthquake oscillations the properties of the soils change and always in the direction, in terms of their role in relation to the building and the support of the building over them. The effects of earthquake shaking need to always be considered in geotechnical engineering practice and frequently are found to govern design. In this regard will be presented a summary of field and laboratory methods for determining soil and rock characteristics used for foundation design for Durres surrounding areas such as Keneta, Thumana and Marsh. The main goal would be a better understanding of site geotechnical performance during earthquakes is desirable in future in urban centers in Albania. This should lead to better foundation performance in order to achieve greater resilience and reparability for the building stock.