Variation of mechanical property and meso structure of MWCNTs concrete exposed to high temperature

被引：2

作者：

Tian W. ^{[1
]}

Gao F.-F. ^{[2
]}

He L. ^{[1
]}

机构：

[1] School of Civil Engineering, Chang’an University, Xi’an

[2] School of Civil Engineering, Lanzhou University of Technology, Lanzhou

来源：

Zhejiang Daxue Xuebao (Gongxue Ban)/Journal of Zhejiang University (Engineering Science) | 2022年 / 56卷 / 11期

关键词：

compressive strength; high temperature; meso structure; MWCNTs concrete; X-ray CT;

D O I：

10.3785/j.issn.1008-973X.2022.11.019

中图分类号：

学科分类号：

摘要：

The action mechanism of multi walled carbon nanotubes (MWCNTs) on the mechanical properties and meso structure of concrete exposed to high temperature was explored. The compressive strength was studied by the uniaxial compression test. The pore characteristics were detected by computer tomography (X-ray CT) technology. The micro morphology and hydration products were observed by scanning electron microscope (SEM). The results showed that the strength loss of MWCNTs in high temperature compared with ordinary plain concrete reinforced concrete decreased by 11.15%—27.60%. The filling and bridging effect of MWCNTs hindered and delayed the expansion of internal cracks in concrete. MWCNTs had a certain beneficial effect on the formation of internal pore network of the concrete below 600 ℃. The influence of cooling mode on the performance of concrete was also considered. The quench cooling caused a strong thermal shock effect, which led to the rapid decline of performance of concrete. The spray cooling was beneficial to the recovery of properties of concrete exposed to high temperature in a short time. The damage degree of the concrete specimen cooled naturally in air was between the above two. © 2022 Zhejiang University. All rights reserved.

引用

页码：2280 / 2289

页数：9

共 36 条

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