Effect of free water on the quasi-static compression behavior of partially-saturated concrete with a fully coupled DEM/CFD approach

IF 2.4 3区工程技术

Granular Matter Pub Date : 2024-03-09 DOI:10.1007/s10035-024-01409-3

M. Krzaczek, J. Tejchman, M. Nitka

{"title":"Effect of free water on the quasi-static compression behavior of partially-saturated concrete with a fully coupled DEM/CFD approach","authors":"M. Krzaczek, J. Tejchman, M. Nitka","doi":"10.1007/s10035-024-01409-3","DOIUrl":null,"url":null,"abstract":"<div><p>The work aims to numerically investigate the quasi-static response of partially fluid-saturated concrete under two-dimensional uniaxial compression at the mesoscale. We investigated how the impact of free pore fluid content (water and gas) affected the quasi-static strength of concrete. The totally and partially fluid-saturated concrete behavior was simulated using an improved pore-scale hydro-mechanical model based on DEM/CFD. The fluid flow concept was based on a fluid flow network made up of channels in a continuous region between discrete elements. A two-phase laminar fluid flow was postulated in partially saturated porous concrete with very low porosity. Position and volumes of pores/cracks were considered to correctly track the liquid/gas content. In both dry and wet conditions, a series of numerical simulations were performed on bonded granular specimens of a simplified spherical mesostructure that mimicked concrete. The effects of fluid saturation and fluid viscosity on concrete strength and fracture, and fluid pore pressures were investigated. It was found that each of those effects significantly impacted the hydro-mechanical behavior of concrete. Due to the rising fluid pressure in pores during initial specimen compaction under compressive loading that promoted a cracking process, the compressive strength increased as fluid saturation and fluid viscosity decreased.</p><h3>Graphical abstract</h3><div><figure><div><div><picture><source><img></source></picture></div><div><p>DEM-CFD results for fully saturated specimen: evolution of maximum pore water pressure against vertical normal strain during uniaxial compression (from zero up to peak stress for).</p></div></div></figure></div></div>","PeriodicalId":49323,"journal":{"name":"Granular Matter","volume":"26 2","pages":""},"PeriodicalIF":2.4000,"publicationDate":"2024-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Granular Matter","FirstCategoryId":"5","ListUrlMain":"https://link.springer.com/article/10.1007/s10035-024-01409-3","RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}

引用次数: 0

Abstract

The work aims to numerically investigate the quasi-static response of partially fluid-saturated concrete under two-dimensional uniaxial compression at the mesoscale. We investigated how the impact of free pore fluid content (water and gas) affected the quasi-static strength of concrete. The totally and partially fluid-saturated concrete behavior was simulated using an improved pore-scale hydro-mechanical model based on DEM/CFD. The fluid flow concept was based on a fluid flow network made up of channels in a continuous region between discrete elements. A two-phase laminar fluid flow was postulated in partially saturated porous concrete with very low porosity. Position and volumes of pores/cracks were considered to correctly track the liquid/gas content. In both dry and wet conditions, a series of numerical simulations were performed on bonded granular specimens of a simplified spherical mesostructure that mimicked concrete. The effects of fluid saturation and fluid viscosity on concrete strength and fracture, and fluid pore pressures were investigated. It was found that each of those effects significantly impacted the hydro-mechanical behavior of concrete. Due to the rising fluid pressure in pores during initial specimen compaction under compressive loading that promoted a cracking process, the compressive strength increased as fluid saturation and fluid viscosity decreased.

Graphical abstract

DEM-CFD results for fully saturated specimen: evolution of maximum pore water pressure against vertical normal strain during uniaxial compression (from zero up to peak stress for).

Abstract Image

查看原文本刊更多论文

利用 DEM/CFD 全耦合方法分析自由水对部分饱和混凝土准静态压缩行为的影响

这项工作旨在对部分流体饱和混凝土在中尺度二维单轴压缩下的准静力响应进行数值研究。我们研究了自由孔隙流体（水和气体）含量对混凝土准静态强度的影响。我们使用基于 DEM/CFD 的改进型孔隙尺度水力机械模型模拟了完全和部分流体饱和混凝土的行为。流体流动的概念基于离散元素之间连续区域内由通道组成的流体流动网络。假设在孔隙率极低的部分饱和多孔混凝土中存在两相层流。考虑了孔隙/裂缝的位置和体积，以正确跟踪液体/气体含量。在干燥和潮湿条件下，对模仿混凝土的简化球形中间结构的粘结颗粒试样进行了一系列数值模拟。研究了流体饱和度和流体粘度对混凝土强度和断裂以及流体孔隙压力的影响。研究发现，这些影响都会对混凝土的水力学行为产生重大影响。由于在抗压荷载下初始试样压实过程中孔隙中的流体压力不断升高，从而促进了开裂过程，因此抗压强度随着流体饱和度和流体粘度的降低而增加。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

Granular Matter MATERIALS SCIENCE, MULTIDISCIPLINARY-MECHANICS

CiteScore

4.30

自引率

8.30%

发文量

期刊介绍： Although many phenomena observed in granular materials are still not yet fully understood, important contributions have been made to further our understanding using modern tools from statistical mechanics, micro-mechanics, and computational science. These modern tools apply to disordered systems, phase transitions, instabilities or intermittent behavior and the performance of discrete particle simulations. >> Until now, however, many of these results were only to be found scattered throughout the literature. Physicists are often unaware of the theories and results published by engineers or other fields - and vice versa. The journal Granular Matter thus serves as an interdisciplinary platform of communication among researchers of various disciplines who are involved in the basic research on granular media. It helps to establish a common language and gather articles under one single roof that up to now have been spread over many journals in a variety of fields. Notwithstanding, highly applied or technical work is beyond the scope of this journal.