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Copyright of Technical Transactions / Czasopismo Techniczne is the property of Sciendo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Technical Transactions / Czasopismo Techniczne is the property of Sciendo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Technical Transactions / Czasopismo Techniczne is the property of Sciendo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The reports after major earthquakes indicate that the earthquake-induced pounding between insufficiently separated buildings may lead to significant damage or even total collapse of structures. An intensive study has recently been carried out on mitigation of pounding hazards so as to minimize the structural damages or prevent collisions at all. The aim of this paper is to investigate the effectiveness of the method when two adjacent three-storey buildings with different (substantially different) dynamic properties are connected at each storey level by link elements (springs, dashpots or viscoelastic elements). The results of the study indicate that connecting the structures by additional link elements can be very beneficial for the lighter and more flexible building. The largest decrease in the response of the structure has been obtained for links with large stiffness or damping values, which stands for the case when two buildings are fully connected and vibrate in-phase. Moreover, by comparing the effectiveness of different types of link elements, it has been confirmed that the use of viscoelastic elements reduces the peak displacement of the structure at lower stiffness and damping values comparing to the case when spring and dashpot elements are applied alone. On the other hand, the results of the study demonstrate that applying the additional link elements does not really change the response of the heavier and stiffer building. The final conclusion of the study indicates that linking two buildings allows us to reduce the in-between gap size substantially while structural pounding can be still prevented. [ABSTRACT FROM AUTHOR]

A class of higher order nonlinear neutral difference equations with quasidifferences is studied. Sufficient conditions under which considered equation has a solution which converges to zero are presented. [ABSTRACT FROM AUTHOR]

The present paper investigates the coupled effect of the supporting soil flexibility and pounding between neighbouring, insufficiently separated equal height buildings under earthquake excitation. Two adjacent three-storey structures, modelled as inelastic lumped mass systems with different structural characteristics, have been considered in the study. The models have been excited using a suit of ground motions with different peak ground accelerations and recorded at different soil types. A nonlinear viscoelastic pounding force model has been employed in order to effectively capture impact forces during collisions. Spring-dashpot elements have been incorporated to simulate the horizontal and rotational movements of the supporting soil. The results of the numerical simulations, in the form of the structural nonlinear responses as well as the time-histories of energy dissipated during pounding-involved vibrations, are presented in the paper. In addition, the variation in storeys peak responses and peak dissipated energies for different gap sizes are also shown and comparisons are made with the results obtained for colliding buildings with fixed-base supports. Observations regarding the incorporation of the soil-structure interaction and its effect on the responses obtained are discussed. The results of the study indicate that the soil-structure interaction significantly influences the pounding-involved responses of equal height buildings during earthquakes, especially the response of the lighter and more flexible structure. It has been found that the soil flexibility decreases storey peak displacements, peak impact forces and peak energies dissipated during vibrations, whereas it usually leads to the increases in the peak accelerations at each storey level. [ABSTRACT FROM AUTHOR]

The phenomenon of earthquake-induced structural pounding has attracted the researchers' attention for several years now. The aim of this paper is to show the results of two experiments concerning interactions between elements made of different building materials, such as steel, concrete, timber and ceramic. The first experiment was conducted by dropping balls from different height levels onto a rigid surface, whereas the second one was focused on pounding-involved response of two tower models excited on a shaking table. The results of the impact experiment show that the value of the coefficient of restitution depends substantially on the prior-impact velocity as well as on the material used. Based on these results, the appropriate formulations have been suggested to be applied in the numerical simulations. The results of the shaking table tests show a considerable influence of the material used for colliding elements on the behaviour of structures during earthquakes. Copyright © 2009 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Earthquake-induced pounding was experienced in many previous earthquakes and it was found to be a critical issue. This study investigates the effect of pounding between buildings founded on the same and different soil types. Three 3-D buildings with 4, 6 and 8 storeys were considered in this study. Three pounding scenarios were taken into account, i.e. pounding between 4-storey and 6-storey buildings, between 4-storey and 8-storey buildings and between 6-storey and 8-storey buildings. To consider the soil type, the effects of different site parameters on the response of buildings exposed to earthquakes was firstly investigated so that the values that lead to significant effects and larger responses could be taken into account in further study related to structural interactions. In the next stage of the investigation, the effects of pounding between buildings founded on a specified soil type were analysed and compared with the no pounding case. The results of this part of this study show that pounding significantly increases the peak accelerations in all situations. Indeed, the peak displacements experience both amplification and de-amplification. Moreover, the shear forces were found to be increased for all storeys in all the cases with few exceptions concerning the top storeys. Finally, pounding between 4-storey and 8-storey buildings as well as between 6-storey and 8-storey buildings was considered under different soil types defined in the ASCE 7–10 code (hard rock, rock, very dense soil and soft rock, stiff soil and soft clay soil). The results of this stage of this study show that the highest displacements and shear forces can be expected for buildings founded on the soft clay soil, then for buildings founded on the stiff soil, then for buildings founded on very dense soil and soft rock, and finally for buildings founded on the rock and hard rock. • Pounding significantly increases accelerations of colliding buildings during the whole duration of the ground motion. • The displacements of colliding buildings experience both amplification and de-amplification. • Pounding significantly increases the storeys shears of the colliding buildings with few exceptions at the top storeys. • Pounding leads to the generation of large impact forces which are not considered in the engineering design. • The soil type has a significant effect on the response of colliding buildings. [ABSTRACT FROM AUTHOR]

• Higher values of the site parameters leads to higher responses. • The effect of pounding could be either destructive or beneficial. • The soil type has a significant effect on the response of the colliding buildings. The effect of the soil type on buildings experiencing pounding during earthquakes is investigated in this study using the incremental dynamic analysis and fragility assessment methods. Three 3-D structures with different number of storeys (4, 6 and 8) were considered in this study. Three pounding scenarios between these three buildings were taken into account, i.e. pounding between 4-storey and 6-storey buildings, between 4-storey and 8-storey buildings and between 6-storey and 8-storey buildings. First, the effect of the site parameters was investigated so as to take into consideration the values that lead to higher responses. Then, the effects of earthquake-induced pounding between buildings founded on a specified soil type for these three pounding scenarios were analysed and compared with no pounding case. Finally, pounding for these three scenarios was studied under different soil types defined in the ASCE 7–10 code (hard rock, rock, very dense soil and soft rock, stiff soil and soft clay soil). The results of this study indicate that the effect of pounding follows two general trends which are destructive and beneficial. Also, the vibrating buildings were found to be more vulnerable to damage due to pounding when they are founded on the soft clay soil, then when they are founded on the stiff soil, then when they are founded on very dense soil and soft rock, and finally when they are founded on the rock and hard rock. [ABSTRACT FROM AUTHOR]

Modelling the epidemic's spread on multiplex networks, considering complex human behaviours, has recently gained the attention of many scientists. In this work, we study the interplay between epidemic spreading and opinion dynamics on multiplex networks. An agent in the epidemic layer could remain in one of five distinct states, resulting in the SIRQD model. The agent's attitude towards respecting the restrictions of the pandemic plays a crucial role in its prevalence. In our model, the agent's point of view could be altered by either conformism mechanism, social pressure, or independent actions. As the underlying opinion model, we leverage the q-voter model. The entire system constitutes a coupled opinion–dynamic model where two distinct processes occur. The question arises of how to properly align these dynamics, i.e., whether they should possess equal or disparate timescales. This paper highlights the impact of different timescales of opinion dynamics on epidemic spreading, focusing on the time and the infection's peak. [ABSTRACT FROM AUTHOR]