The size effect in quasi-brittle materials: Experimental and numerical analysis

Author:

Colpo Angélica Bordin1,Kosteski Luis Eduardo1,Iturrioz Ignacio2

Affiliation:

1. Post-Graduate Program in Engineering (PPEng), Federal University of Pampa (UNIPAMPA), Brazil

2. Post-Graduate Program in Mechanical Engineering (PROMEC), Federal University of Rio Grande do Sul (UFRGS), Brazil

Abstract

The size effect in structures is responsible for the materials apparent properties variations as function of size. Different methodologies are proposed in the literature to address this phenomenon; however, there is still no consensus on how to specifically deal with this. For instance, if the material investigated were a quasi-brittle material, it would present a fissures development in different scales during the damaging process. In the present work, an experimental study applying uniaxial tension over expanded polystyrene specimens of different sizes is proposed. The acoustic emission events occurring during the tests were also recorded. A tailored version of a lattice discrete element method was used to simulate the tests. This numerical approach take into account several phenomena related with the damage process in quasi-brittle materials, such as the localization effect, the fractal dimension nature of the region over which the damage evolves; the collaborative effect between cluster of fissures and the avalanche effect during the damage process. It is important to mention that these characteristics are associated with the correct simulation of the acoustic emission registry. The obtained experimental and simulated results were in great agreement and clearly showed a size effect, despite the narrow range of dimension explored. The size effect evaluated during the simulations, in terms of the dissipated energy, is shown to be in agreement to the known fractal theory proposed by Alberto Carpinteri and coworkers. Moreover, results in terms of acoustic emission are preliminarily explored to determine the correlation between the acoustic emission events and the fracture mode that governs the source of these events. Finally, some conclusions related to the size effect captured during the tests and the possibilities for simulations of the fracturing process in quasi-brittle materials provided by the numerical method are point out.

Publisher

SAGE Publications

Subject

Mechanical Engineering,Mechanics of Materials,General Materials Science,Computational Mechanics

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3