PSI - Issue 44

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ScienceDirect

Procedia Structural Integrity 44 (2023) 2136–2143 Structural Integrity Procedia 00 (2022) 000–000 Structural Integrity Procedia 00 (2022) 000–000

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© 2023 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the scientific committee of the XIX ANIDIS Conference, Seismic Engineering in Italy. Abstract This paper analyses the e ff ectiveness of connecting the first storey of a frame structure to an external structure shorter than the frame structure by a visco-elastic device. Additionally, an inerter device is applied to the external structure to modify its inertial force and increase the e ff ectiveness of the coupling. The coupled structure is modeled as a three-degree-of-freedom mechanical system, and its equations of motion are obtained by a direct approach. The coupling with the external structure is considered beneficial for the frame structure if the absolute displacements of the coupling level or the inter-storey drifts reduce compared to those of the stand-alone frame structure. A preliminary modal analysis shows that the coupling with the external structure equipped with the inerter device improves the dynamic and seismic performances of the system. A further analysis is performed by considering some ground motion records. The results, organized in performance maps, confirm that the coupling with the external structure reduces the displacements and drifts of the frame structure in large ranges of values of the parameters that characterize the external structure and connection device. c 2022 The Authors. Published by Elsevier B.V. is is an open access article under the CC BY-NC-ND license (http: // cr ativec mmons.org / licenses / by-nc-nd / 4.0 / ) r-review unde responsibility of the scientific committee of the XIX ANIDIS Conf rence, Se smic Engineering in Italy. Keywords: Frame structure; external structure; visco-elastic coupling; inerter device; partial connection; seismic performances. XIX ANIDIS Conference, Seismic Engineering in Italy Improvement of the seismic response of frame structures through the coupling with an external structure equipped with inerter A. Di Egidio a, ∗ , S. Pagliaro a , A. Contento a a University of L’Aquila - DICEAA, via G. Gronchi 19, 67100 L’Aquila, Italy Abstract This paper analyses the e ff ectiveness of connecting the first storey of a frame structure to an external structure shorter than the frame structure by a visco-elastic device. Additionally, an inerter device is applied to the external structure to modify its inertial force and increase the e ff ectiveness of the coupling. The coupled structure is modeled as a three-degree-of-freedom mechanical system, and its equations of motion are obtained by a direct approach. The coupling with the external structure is considered beneficial for the frame structure if the absolute displacements of the coupling level or the inter-storey drifts reduce compared to those of the stand-alone frame structure. A preliminary modal analysis shows that the coupling with the external structure equipped with the inerter device improves the dynamic and seismic performances of the system. A further analysis is performed by considering some ground motion records. The results, organized in performance maps, confirm that the coupling with the external structure reduces the displacements and drifts of the frame structure in large ranges of values of the parameters that characterize the external structure and connection device. c 2022 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http: // creativecommons.org / licenses / by-nc-nd / 4.0 / ) Peer-review under responsibility of the scientific committee of the XIX ANIDIS Conference, Seismic Engineering in Italy. Keywords: Frame structure; external structure; visco-elastic coupling; inerter device; partial connection; seismic performances. XIX ANIDIS Conference, Seismic Engineering in Italy Improvement of the seismic response of frame structures through the coupling with an external structure equipped with inerter A. Di Egidio a, ∗ , S. Pagliaro a , A. Contento a a University of L’Aquila - DICEAA, via G. Gronchi 19, 67100 L’Aquila, Italy

1. Introduction 1. Introduction

Many researchers used low-dimensional mechanical models (also called archetype models) to capture the main dynamic and seismic aspects of real structures. For instance, two-Degree-Of-Freedom (2-DOF) models were used to study the conceptual aspects of the base isolation technique in Kelly (1995) or of Tuned Mass Damper (TMD) system in Den Hartog (1956). Low-dimensional models were also used to investigate other structural schemes. Paper Bachmann et al. (2017) investigated the dynamic behavior of a frame structure placed on a rocking podium with a low-dimensional model. Instead, an archetype model was used in Di Egidio et al. (2021) where the improvement of the dynamic and seismic performances of frame structures was obtained by connecting an external rocking wall to the first storey of the frame structures through a visco-elastic device. Paper Pietrosanti et al. (2020) used an interstorey Many researchers used low-dimensional mechanical models (also called archetype models) to capture the main dynamic and seismic aspects of real structures. For instance, two-Degree-Of-Freedom (2-DOF) models were used to study the conceptual aspects of the base isolation technique in Kelly (1995) or of Tuned Mass Damper (TMD) system in Den Hartog (1956). Low-dimensional models were also used to investigate other structural schemes. Paper Bachmann et al. (2017) investigated the dynamic behavior of a frame structure placed on a rocking podium with a low-dimensional model. Instead, an archetype model was used in Di Egidio et al. (2021) where the improvement of the dynamic and seismic performances of frame structures was obtained by connecting an external rocking wall to the first storey of the frame structures through a visco-elastic device. Paper Pietrosanti et al. (2020) used an interstorey

∗ Corresponding author. Tel.: + 39 0862 434530. E-mail address: angelo.diegidio@univaq.it 2452-3216 c 2022 The Authors. Published by Elsevier B.V. ∗ Corresponding author. Tel.: + 39 0862 434530. E-mail address: angelo.diegidio@univaq.it 2452-3216 c 2022 The Authors. Published by Elsevier B.V.

2452-3216 © 2023 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the scientific committee of the XIX ANIDIS Conference, Seismic Engineering in Italy. 10.1016/j.prostr.2023.01.273 This is an open access article under the CC BY-NC-ND license (http: // creativecommons.org / licenses / by-nc-nd / 4.0 / ) Peer-review under responsibility of the scientific committee of the XIX ANIDIS Conference, Seismic Engineering in Italy. This is an open access article under the CC BY-NC-ND license (http: // creativecommons.org / licenses / by-nc-nd / 4.0 / ) Peer-review under responsibility of the scientific committee of the XIX ANIDIS Conference, Seismic Engineering in Italy.