ABSTRACT
The numerical assessment of masonry arch-type viaduct subjected to foreshocks and a mainshock seismic sequence is presented in this work. As a case study, the masonry arch-type viaduct erected in Krakow (Southern Poland) in XIX century was chosen. For the study purposes, 3D finite element model (FEM) of the viaduct was prepared with ABAQUS/Standard software program. The main objective of the analysis is the comparison of the dynamic performance of two variants of the structure under the investigated seismic sequence. The first variant of the viaduct was the structure without any strengthening, whereas the second variant was with strengthening system realized by application composite materials, i.e. Fibre Reinforced Cementitious Matrix (FRCM). In dynamic analysis of both variants the Barcelona Model (BM) was applied as a constitutive material model to represent nonlinear behaviour of the masonry arches under the seismic actions. The results of dynamic analysis revealed that evident nonlinear performance of the masonry arches was detected for both models of structure. The analysis proved that the foreshock-mainshock sequence caused substantial damages in structural parts of the viaduct. The distribution of plastic strains and damages allowed to assess the impact of the full foreshock-mainshock sequence on the masonry arches of viaduct. In case of the unstrengthen viaduct the level of cracking and stiffness loss reached 90%. In case of the viaduct strengthened with the FRCM system the tensile damage level was significantly lower. It did not exceed 30%. It also occurred that the first plastic zone of the unstrengthen masonry arches of the viaduct was reported already after the 1st foreshock.
