文献类型：期刊文献

英文题名：Experiment and modelling of degradation mechanism of cement mortar with graphene oxide nanosheets under sulfate attack

作者：Zeng, Hongyan[1,2,3];Zhou, Ruichen[1];Yu, Jing[3];Hu, Yunjin[1];Qu, Shen[4];Chen, Junbin[1];Hou, Shaodan[1]

机构：[1]Shaoxing Univ, Sch Civil Engn, Shaoxing 312000, Peoples R China;[2]Key Lab Rock Mech & Geohazards Zhejiang Prov, Shaoxing 312000, Peoples R China;[3]Univ Hong Kong, Dept Civil Engn, Pokfulam, Hong Kong, Peoples R China;[4]Zhejiang Ind Polytech Coll, Dept Civil Engn & Architecture, Shaoxing 312000, Peoples R China

年份：2025

卷号：155

外文期刊名：CEMENT & CONCRETE COMPOSITES

收录：SCI-EXPANDED(收录号：WOS:001351426500001)、、EI(收录号：20244517314536)、Scopus(收录号：2-s2.0-85207871729)、WOS

基金：This study was supported by Zhejiang Provincial Natural Science Foundation (LQ23D010002) , Scientific Research Fund of Zhejiang Provincial Education Department (Y202248582, Y202455558) , Special Fund of Hangzhou Iron and Steel Group Co., Ltd (XKZ202212027) , Shaoxing Science and Technology Plan Project (2023A13006) , and Research Projects of Shaoxing University (2022LG008) .

语种：英文

外文关键词：Concrete durability; Cement mortar; Graphene oxide; Sulfate attack; Transport model; Degradation mechanism

外文摘要：Degradation of cementitious materials caused by sulfate attack poses a significantly challenge to their durability. Using nano-additives to enhance the mechanical and durability properties of cementitious materials is a promising solution; however, the impact of graphene oxide (GO) on the sulfate resistance is not yet fully understood. While efforts have been made to study the degradation mechanism through accelerated indoor tests with high sulfate concentrations, these methods fail to accurately replicate real-world field exposure conditions. To better understand the degradation mechanism of GO-modified mortars under actual field conditions, this study examines the long-term degradation (over 24 months) of GO-modified mortars exposed to sulfate solutions with varying concentrations: 0 % (reference), 2.1 % (field condition), 5 % (laboratory condition), and 15 % (high-concentration condition). Additionally, a comprehensive chemo-mechanical model that considers multiple factors and time-varying boundary conditions was proposed. The study thoroughly discusses the effects of GO dosage, sulfate concentration, and exposure time on the degradation mechanism. Comparison with experimental data revealed that cement mortar degradation under sulfate attack is primarily driven by the crystallization pressure related to ettringite formation in diluted sulfate solutions, while the precipitation of alkali ions from mortar pore solutions occurs in concentrated sulfate solutions. In real-field conditions, cement mortar degradation primarily involves gypsum precipitation rather than ettringite formation. This study demonstrates that well-dispersed GO nanosheets can significantly enhance durability of cementitious materials against sulfate attack, offering valuable insights for strategic applications of GO nanosheets in cementitious materials.