Cargando…
Discrete Element Mesoscale Modeling of Recycled Lump Concrete under Axial Compression
In the past decade, directly reusing large pieces of coarsely crushed concrete (referred to as demolished concrete lumps or DCLs) with fresh concrete in new construction was demonstrated as an efficient technique for the recycling of waste concrete. Previous studies investigated the mechanical prope...
Autores principales: | , |
---|---|
Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
MDPI
2019
|
Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6804228/ https://www.ncbi.nlm.nih.gov/pubmed/31561478 http://dx.doi.org/10.3390/ma12193140 |
_version_ | 1783461136241262592 |
---|---|
author | Yu, Yong Wu, Bo |
author_facet | Yu, Yong Wu, Bo |
author_sort | Yu, Yong |
collection | PubMed |
description | In the past decade, directly reusing large pieces of coarsely crushed concrete (referred to as demolished concrete lumps or DCLs) with fresh concrete in new construction was demonstrated as an efficient technique for the recycling of waste concrete. Previous studies investigated the mechanical properties of recycled lump concrete (RLC) containing different sizes of DCLs; however, for actual application of this kind of concrete, little information is known about the influence of the spatial locations of DCLs and coarse aggregates on the concrete strength. Moreover, the mechanical responses of such a concrete containing various shapes of DCLs are also not well illustrated. To add knowledge related to these topics, two-dimensional mesoscale simulations of RLC containing DCLs under axial compression were performed using the discrete element method. The main variables of interest were the relative strength of the new and old concrete, the distribution of the lumps and other coarse aggregates, and the shape of the lumps. In addition, the differences in compression behavior between RLC and recycled aggregate concrete were also predicted. The numerical results indicate that the influence tendency of the spatial locations of DCLs and coarse aggregate pieces on the compressive stress–strain curves for RLC is similar to that of the locations of coarse aggregates for ordinary concrete. The strength variability of RLC is generally higher than that of ordinary concrete, regardless of the relative strength of the new and old concrete included; however, variability has no monotonic trend with an increase in the lump replacement ratio. The mechanical properties of RLC in compression are little influenced by the geometric shape of DCLs as long as the ratio of the length of their long axis to short axis is smaller than 2.0. The compressive strength and elastic modulus of RLC are always superior to those of recycled aggregate concrete designed with a conventional mixing method. |
format | Online Article Text |
id | pubmed-6804228 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2019 |
publisher | MDPI |
record_format | MEDLINE/PubMed |
spelling | pubmed-68042282019-11-18 Discrete Element Mesoscale Modeling of Recycled Lump Concrete under Axial Compression Yu, Yong Wu, Bo Materials (Basel) Article In the past decade, directly reusing large pieces of coarsely crushed concrete (referred to as demolished concrete lumps or DCLs) with fresh concrete in new construction was demonstrated as an efficient technique for the recycling of waste concrete. Previous studies investigated the mechanical properties of recycled lump concrete (RLC) containing different sizes of DCLs; however, for actual application of this kind of concrete, little information is known about the influence of the spatial locations of DCLs and coarse aggregates on the concrete strength. Moreover, the mechanical responses of such a concrete containing various shapes of DCLs are also not well illustrated. To add knowledge related to these topics, two-dimensional mesoscale simulations of RLC containing DCLs under axial compression were performed using the discrete element method. The main variables of interest were the relative strength of the new and old concrete, the distribution of the lumps and other coarse aggregates, and the shape of the lumps. In addition, the differences in compression behavior between RLC and recycled aggregate concrete were also predicted. The numerical results indicate that the influence tendency of the spatial locations of DCLs and coarse aggregate pieces on the compressive stress–strain curves for RLC is similar to that of the locations of coarse aggregates for ordinary concrete. The strength variability of RLC is generally higher than that of ordinary concrete, regardless of the relative strength of the new and old concrete included; however, variability has no monotonic trend with an increase in the lump replacement ratio. The mechanical properties of RLC in compression are little influenced by the geometric shape of DCLs as long as the ratio of the length of their long axis to short axis is smaller than 2.0. The compressive strength and elastic modulus of RLC are always superior to those of recycled aggregate concrete designed with a conventional mixing method. MDPI 2019-09-26 /pmc/articles/PMC6804228/ /pubmed/31561478 http://dx.doi.org/10.3390/ma12193140 Text en © 2019 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/). |
spellingShingle | Article Yu, Yong Wu, Bo Discrete Element Mesoscale Modeling of Recycled Lump Concrete under Axial Compression |
title | Discrete Element Mesoscale Modeling of Recycled Lump Concrete under Axial Compression |
title_full | Discrete Element Mesoscale Modeling of Recycled Lump Concrete under Axial Compression |
title_fullStr | Discrete Element Mesoscale Modeling of Recycled Lump Concrete under Axial Compression |
title_full_unstemmed | Discrete Element Mesoscale Modeling of Recycled Lump Concrete under Axial Compression |
title_short | Discrete Element Mesoscale Modeling of Recycled Lump Concrete under Axial Compression |
title_sort | discrete element mesoscale modeling of recycled lump concrete under axial compression |
topic | Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6804228/ https://www.ncbi.nlm.nih.gov/pubmed/31561478 http://dx.doi.org/10.3390/ma12193140 |
work_keys_str_mv | AT yuyong discreteelementmesoscalemodelingofrecycledlumpconcreteunderaxialcompression AT wubo discreteelementmesoscalemodelingofrecycledlumpconcreteunderaxialcompression |