On the thermal spalling mechanism of reactive powder concrete exposed to high temperature: Numerical and experimental studies
On the thermal spalling mechanism of reactive powder concrete exposed to high temperature: Numerical and experimental studies
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DOI：
10.1016/j.ijheatmasstransfer.2016.03.033
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发表时间：
2016-07-01
影响因子：
5.2
通讯作者：
Ge, Zhishun
中科院分区：
文献类型：
--
作者：
Ju, Yang;Liu, Jinhui;Ge, Zhishun
混凝土在高温下的剥落严重危害了整个结构的完整性。对于剥离风险有许多解释，但很少有模型能准确预测它。提出了一种定量描述RPC在高温下破坏性剥落的内在机制的数值方法。该模型在COMSOL多物理中实现，有限元方法作为基本的应力分析工具。采用最大拉应力准则和变形能密度理论作为层裂破坏门槛。分析了RPC的内部温度场、应力场、层裂分布及演化过程。结果表明，数值模拟结果与RPC剥落的实验观测结果吻合较好。基于数值计算和试验结果，提出了一个概念模型来解释RPC的渐进性剥落破坏机理。(C)2016爱思唯尔有限公司。保留所有权利。
Concrete spalling at high temperature seriously jeopardizes the integrity of the entire structure. Many explanations for the spalling risk exist, but few models can accurately predict it. A numerical approach to quantitatively characterizing the intrinsic mechanism that governs the devastating spalling of RPC at high temperature is presented. The proposed model is implemented in COMSOL MULTIPHYSICS, and the finite element method is employed as the basic stress analysis tool. The maximum tensile stress criterion and the distortion energy density theory are utilized as the spalling failure thresholds. The interior temperature field, stress field, spalling distribution and evolution of RPC are analyzed accordingly. It is shown that the numerical simulation results are in good agreement with the experimental observations of RPC's spalling. A conceptual model is proposed to elucidate the mechanism that induces the progressive spalling failure of RPC based on the numerical and experimental results. (C) 2016 Elsevier Ltd. All rights reserved.