Model for the seismic performance assessment of masonry houses in Škofja Loka region

Two models for seismic performance assessment of masonry houses in Škofja Loka region are developed. In first chapters the behaviour of masonry buildings under seismic actions with an emphasis on failure mechanisms of structural components are discussed. Follows an overview of the theoretical background of N2 method, which is included in the Eurocode 8 and which was used for determination of the seismic resistance of examined masonry structures. The results of numerical investigation of 11 masonry houses, built in the years from 1970 to 1990, are then presented and discussed. The project design for building permit was used to obtain input data of the buildings. The mean values and the coefficient of variation were assessed for those geometrical features of the buildings, which have great impact on the seismic performance assessment of the buildings. Expected percentage of the floor surface area of the walls in relation to the net surface of the floor varied from 11 to 12 % with respect to the direction of building. The proportion of the effective floor area of the\ud walls is in the range from 60 to 90% of the gross surface area of the walls depending on the direction of the building. Average wall is 2,4 m wide and its effective height amounts to 80 % of the building`s floor height. It was found that the selected characteristics of houses with the corresponding data which are available on the web portal e-Prostor, are significantly different. Nonlinear static (pushover) analysis was performed by using computer software 3Muri. The results show that the combination of bending and shear damage occurred in piers and also spandrels in the region of deformation close to the ultimate limit state. Two models of the normalized expected pushover curves were obtained by taking into account the\ud pushover curves which had a decisive impact on the seismic limit-state peak ground acceleration. The base shear was normalized by the weight of the building or with respect to\ud the average effective floor area of the walls in the given direction and whereas the top displacement was normalized only by the building’s height. Maximum expected capacity in\ud weak direction amounted 15 % of the total weight of the building and more than 60 kN per square meter of effective floor area of the walls. In the last chapter the normalized pushover curves were used for seismic performance assessment of two houses for which it was found that do not fulfil requirements of standard Eurocode 8-3