Mechanism Analysis of a Sulfate Complex Salt Improving Early Tensile Strength of Concrete

被引：0

作者：

Sun Z. ^{[1
,2
,3
]}

Geng Y. ^{[1
,2
]}

Yang H. ^{[1
,2
]}

Ji Y. ^{[1
,2
]}

Wang Y. ^{[1
,2
]}

机构：

[1] Key Laboratory of Advanced Civil Engineering Materials of Ministry of Education, Tongji University, Shanghai

[2] School of Materials Science and Engineering, Tongji University, Shanghai

[3] Research Center of Intelligent Evaluation and Restoration Engineering Technology of Urban Pipe Network, Shanghai Water Bureau, Shanghai

来源：

Jianzhu Cailiao Xuebao/Journal of Building Materials | 2022年 / 25卷 / 10期

关键词：

concrete; hydration product; microfiber reinforcement; sulfate complex salt; tensile strength;

D O I：

10.3969/j.issn.1007-9629.2022.10.001

中图分类号：

学科分类号：

摘要：

The effect of a sulfate complex salt （SN） was studied by axial tensile test of concrete in the present investigation. The phase composition and morphological structure of hardened paste were characterized by X‑ray diffraction （XRD）， thermogravimetric‑derivative thermogravimetric （TG‑DTG） analysis and scanning electron microscope （SEM）. Combined with the hydration heat release of cementitious system， the working mechanism of SN was discussed. The results show that the early tensile strength of concrete can be significantly improved by using SN. Specifically， compared to the control， the tensile strength at the age of 1， 3, 5 d is increased by 18.7%， 23.6% and 16.2%， respectively， while 2.0% SN is dosed into concrete， no obvious adverse effect occurs on the tensile strength at later ages. The incorporation of SN can speed up the early hydration process of cementitious system and promote the formation of hydration products such as ettringite （AFt）， calcium hydroxide （CH） and calcium silicate hydrate （C‑S‑H） in the cementitious system. Further， the C‑S‑H is filled in the micro lap‑structure formed by needle‑shaped AFt， which is beneficial to the uniform distribution of tensile strength and effectively improve the early tensile strength of concrete. © 2022 Tongji University. All rights reserved.

引用

页码：999 / 1006

页数：7

共 16 条

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