Evaluation of the dynamic response of structures using auxetic-type base isolation

Abstract

Base isolation is a widely-used method used to minimise the harmful effects of earthquakes on buildings. Unlike a fixed base building, a building with a base isolation system essentially decouples the superstructure from the substructure resting on the ground. Then, during earthquakes, the superstructure's relative displacement is significantly reduced, minimising the structural damage. Auxetics, which are materials with a negative Poisson's ratio, are known for possessing properties such as high energy absorption. Based on the energy absorbing capabilities of auxetic materials, it is proposed that incorporating them into base isolation structures would positively impact on the performance of the system. Therefore, the article aims to investigate the response of structures under seismic loading incorporating re-entrant hexagon layers into the base isolation system. This is assessed by defining and numerically testing the system using finite element analysis. The models developed for this study represent multi-story structural steel frames combined with fixed base, conventional lead-rubber bearing and auxetic composite base isolation. Differences in the response obtained from the mentioned systems are highlighted. Results indicate that the auxetic base isolation may improve the dynamic response of structures, although a unique performance is not recorded.

Behavior of a Multi-Story Steel Structure with Eccentric X-Brace

“…During a seismic event, the steel-braced frames added to the structure dissipate energy. These frameworks deform plastically under tension and collapse under compression, whereas beams and columns are intended to remain in the elastic zone [1][2][3][4]. Eccentrically braced frames are a modern lateral force-resisting system designed to effectively and predictably sustain seismic events.…”

The Effectiveness of CFRP- and Auxetic Fabric-Strengthened Brick Masonry under Axial Compression: A Numerical Investigation

“…Auxetic fabrics with NPR experience elongation (or contraction) in both in-plane directions when they are stretched (or compressed). Different auxetic geometries with various modifications have been used in mitigating structural damage under seismic loading [39][40][41][42], for the crashworthiness of road vehicles [43], in aerospace engineering structures [44], in biomedical engineering [45][46][47] and in textile technology, indicating a wide range of applications [48]. These industries have prospered due to the enhancement of mechanical properties such as fracture, toughness, indentation resistance, shear modulus and vibration absorption [49][50][51].…”