To cite this article: Joanna Maria Dulinska & Izabela Joanna Murzyn (2016) Dynamic behaviour of a concrete building under a mainshock-aftershock seismic sequence with a concrete damage plasticity material model, Geomatics, Natural Hazards and Risk, 7:sup1, 25-34, DOI: 10.1080/19475705.2016 ABSTRACTThe aim of this paper was to investigate the dynamic response of a concrete structure subjected to a mainshockÀaftershock seismic sequence. In the dynamic analysis, three components of the registered mainshock and aftershock were taken into account. The peak ground accelerations of about 0.5 g were assumed for both shocks. A one-storey shed was modelled with the ABAQUS software to represent a large concrete structure under the repeated earthquakes. For proper characterization of concrete structure behaviour under the sequence of shocks, a concrete damage plasticity model was assumed as a constitutive model of concrete. The obtained results indicate that aftershocks can have considerable effect on dynamic behaviour of concrete structures in terms of enlarging zones affected by irreversible strains or additional damage evolution. The analysis revealed that aftershocks, which are usually not as strong as mainshocks, may result even in total loss of concrete material strength while performing in mainshockÀaftershock seismic sequences.

In the paper a non-linear dynamic response of a concrete highway tunnel to a natural earthquake is presented. The acceleration time history of the registered shock was applied as seismic excitation acting in three directions. The peak ground acceleration (PGA) of the shock was 0.5 g. A three-dimensional FE model of the concrete tunnel section (600 m long) and surrounding soil layers was created with the ABAQUS software. To represent the inelastic behavior of the tunnel under the earthquake, a concrete damage plasticity model was assumed as a constitutive model for the concrete. A model of spatially varying ground motion, which takes so called “wave passage effect” was implemented for the dynamic analysis. Two velocities of seismic wave propagation were assumed: 500 and 1000 m/s. These velocities are typical for soft and stiff bedrock, respectively. It turned out that in case of stiffer bedrock, in which seismic waves propagate faster, the damage pattern shows less cracking than in case of soft bedrock. The distribution of plastic and damage computed indices also allowed to assess the impact of the shock on the structure. It turned out that the analyzed shock with PGA of 0.5 g was strong enough to cause severe destruction (cracking) in the tunnel lining. Finally, the transverse pattern of cracks, that was obtained from the calculations, was in good agreement with damages observed during severe earthquakes.

The aim of this paper was to investigate the dynamic response of a concrete tunnel subjected to mainshock–aftershock seismic sequence. Three components of the registered seismic saquence were applied as seismic excitation acting in three directions. A three-dimensional FE model of a tunnel section (600 m long) was prepared with the ABAQUS software. The soil layers interacting with the tunnel lining were also taken into consideration. To represent the inelastic behavior of the concrete material under the earthquakes, a concrete damage plasticity model (CDP) was assumed a constitutive model for the concrete. The analysis proved that strongly nonlinear behaviour of the concrete lining of the tunnel was observed under the sequence of seismic events. The plastic strains as well the tensile damage (cracking) were noticed in some zones of the concrete lining after the first and the second event. The crack patterns were in good agreement with damages observed on concrete tunnels during real earthquakes. The results indicate that aftershocks can enlarge zones affected by irreversible strains or cause damage evolution. The analysis also revealed that aftershocks, even being much weaker than main events, may result in additional loss of concrete material strength while performing in mainshock-aftershock seismic sequences and striking a structure which is already degraded by a mainshock.