TY - JOUR AU - Ferreira, Guilherme Vaz AU - Levy Neto, Flaminio PY - 2017/02/10 Y2 - 2024/03/28 TI - MODAL ANALYSIS OF HYBRID ADAPTATIVE BEAMS JF - Revista Interdisciplinar de Pesquisa em Engenharia JA - Rev. Interd. Pesq. Eng. VL - 2 IS - 29 SE - Artigos DO - 10.26512/ripe.v2i29.21787 UR - https://periodicos.unb.br/index.php/ripe/article/view/21787 SP - 13-26 AB - <p>Smart or adaptative structures are those capable to perform some special functions&nbsp;when stimulated externally. In the context of this type of structure, hybrid adaptative&nbsp;composite beams, reinforced with active Ni-Ti filaments, were simulated in the present work.&nbsp;Such beams may be adopted for vibration control, exploring the possibility of changing their&nbsp;bending stiffness by means of controlling the temperature of the shape memory alloy&nbsp;filaments. The main objective of this paper is to present, for a free-free boundary condition,&nbsp;the vibration modes and their frequencies obtained analytically and numerically for prismatic&nbsp;beams, which incorporate nineteen layers of epoxy reinforced with chopped E-glass mat (17&nbsp;plies), and two symmetric active plies (A) embedded with up to four Ni-Ti wires each&nbsp;(2+A+13+A+2). One particular aspect of this investigation is to verify how the natural&nbsp;frequency of the beams changes, when an electric current passes through the Ni-Ti wires and&nbsp;elevates their temperature from 25 ºC to 69 ºC, converting 100% of the Ni-Ti wires into the&nbsp;more rigid austenitic phase. In order to verify the accuracy of the analytical method, it was&nbsp;compared with two numerical models based on the finite element method. The maximum&nbsp;differences between the methodologies, in module, was 4.50%.</p> ER -