Search

Nonlinear static analysis, known as a pushover method (NSPA) is oftenly used to study the behaviour of a bridge structure under the seismic action. It is shown that the Equivalent Linearization Method - ELM, recommended in FEMA 440, is appropriate for the response analysis of the bridge columns, with different geometric characteristics, quantity and distribution of steel reinforcement. The subject of analysis is a bridge structure with a carriageway plate - a continuous beam with three spans, with the 24 + 40 + 24 m range. Main girder is made of prestressed concrete and it has a box cross section of a constant height. It is important to study the behaviour, not only in the transverse, but also in the longitudinal direction of the bridge axis, when analysing the bridge columns exposed to horizontal seismic actions. The columns were designed according to EN1992, parts 1 and 2. Seismic action analysis is conducted according to EN 1998: 2004 standard. Response spectrum type 1, for the ground type B, was applied and the analysis also includes 20% of traffic load. The analysis includes the values of columns displacement and ductility. To describe the behaviour of elements under the earthquake action in both - longitudinal and transverse direction, pushover curves were formed.

Energy dissipation and stiffness degradation are important seismic performance indicators within the numerical modelling of structures, and in this case particularly of masonry. They are of great importance for evaluation of the seismic performance of masonry walls. An example of an existing masonry residential building located in Sarajevo, Bosnia and Herzegovina was investigated in this paper. It was observed that during the response of the building to horizontal actions the stiffness degradation of masonry walls was evident.