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  • Author: K. Wasilewski x
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Constitutive Modelling and Numerical Implementation of SMA Material with Internal Loops

Abstract

The article presents a constitutive model for Shape Memory Alloys (SMA) along with result of dynamic simulations of SMA model. The applications of devices incorporating SMA in civil engineering focus mostly on mitigation of the seismic hazard effects in new-build and historical buildings or improvement of fatigue resilience. The unique properties of SMA, such as shape memory effect and superelasticity give promising results for such applications. The presented model includes additional phenomenon of SMA – internal loops. The paper shows the method of formulation of physical relations of SMA based on special rheological structure, which includes modified Kepes’s model. This rheological element, introduced as dual-phase plasticity body, is given in the context of martensite phase transformation. One of the advantages of such an approach is a possibility of formulation of constitutive relationships as a set of explicit differential equations. The application of the model is demonstrated on example of dynamic simulations of three dimensional finite element subjected to dynamic excitation.

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The Polish People’s Republic State Apparatus and the Roma people in the Lubuskie Region

Abstract

The article analyzes the situation of the Roma people in the Lubuskie Region in the years 1945-1989. Being part of the so-called “Western Territories”, the Lubuskie Region, first as the Zielona Góra Voivodship and later divided into Zielona Góra Voivodship and Gorzów Voivodship, attracted a number of ethnic minorities, including Gypsies. “e article presents how local political and security authorities reacted to the presence of the Roma people, adapting central laws, most notably the 1964 forced settlement bill, to local situation. In their analysis, the authors use documents held in various local and central archives, including the Institute of National Remembrance archive and Ministry of the Interior archive.

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Numerical Verification of the Wooden Structure of Fortified Settlement from the Early Iron Age in Biskupin

Abstract

Biskupin is one of the most recognizable archaeological site in Pola1nd and Central Europe. The origins of the excavations dates back to year 1934 and had lasted almost continuously until 1974. In the framework of the grant from the Ministry of Culture and National Heritage interdisciplinary team of scientists from Archaeological Museum in Biskupin and Warsaw University of Technology performed multi-dimensional analysis of the settlement. Based on the integrated vector documentation, resulting from the photographic documentation, numerical models of structural systems of main types of buildings and defensive rampart were prepared. The aim of the analysis was a verification of the earlier findings of archaeological and architectural researches. The analysis allowed to verify both the arrangement of individual parts of structure of buildings, their work and the interconnection, as well as the possible dimensions of the individual components.

Open access