Study of effective thermal conductivity of cracked concrete: three-dimensional simulation and experimental validation

被引：0

作者：

Shen L. ^{[1
]}

Ren Q. ^{[1
]}

Zhang L. ^{[1
]}

Han Y. ^{[1
]}

机构：

[1] Hohai University, Nanjing

来源：

Shuili Xuebao/Journal of Hydraulic Engineering | 2017年 / 48卷 / 06期

关键词：

Cracked concrete; Effective thermal conductivity; Experiment; Meso-scale simulation; Wang model;

D O I：

10.13243/j.cnki.slxb.20160768

中图分类号：

学科分类号：

摘要：

A mesoscopic numerical method is proposed to investigate the effective thermal conductivity (ETC) of both tensile and compressive cracked concrete, and this method is applied to obtain the quantitative relationships between tensile or compressive strain and ETC, respectively. The main conclusions are drawn as follows:(a) for tensile dominated failure, concrete ETC decreases by 23% during plastic stage whereas a very slight linear decrease is found at complete failure;(b) for compressive dominated failure, ETC decreases by 30% during earlier plastic stage, and then becomes steady afterwards. In the softening stage, ETC linearly decreases with the increase of compressive strain;(c) it is the interfacial thermal resistance induced by the micro-cracks between aggregates and mortar rather than the macro-cracks that play the dominant role in this phenomenon;(d) concrete ETC shows more anisotropy when cracks appear. Then an experimental validation of compressive cracked concrete's ETC vertical to cracks (C-ETCV) shows that C-ETCV decreases by 20% ~ 25% at earlier plastic stage and then becomes steady at later plastic stage. The numerical results obtained simulations are used to determine the interfacial thermal resistance factor in Wang model. A good agreement between the data from simulation, Wang model and experiment indicates the correctness of this study. © 2017, China Water Power Press. All right reserved.

引用

页码：689 / 701

页数：12

共 25 条

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