摘要
为满足相关工程外包混凝土要求,制备了C60细石自密实混凝土(SCC),研究了水胶比、抗裂剂对细石SCC工作性能、力学性能、体积变形性能以及抗硫酸盐侵蚀、抗氯离子渗透、抗冻融、抗碳化等耐久性能的影响机制,探讨了细石混凝土性能变化规律.经SEM、NMR等试验探究了不同因素对混凝土的微观结构影响,并与宏观性能进行对比分析.结果表明:水胶比对细石混凝土性能影响机制与普通混凝土类似;抗裂剂存在最佳掺量点,适量抗裂剂可生成Mg(OH)_2填充基体孔隙,与絮状水化硅酸钙(C-S-H)、针状钙矾石(AFt)交错生长,改善孔结构,提高细石混凝土力学性能及耐久性能,但掺量过多时复合侵蚀效应反而使SCC抗硫酸盐侵蚀性能下降,其最优掺量为8%.
To meet the requirements of the outsourced concrete for the relevant project,C60 fine stone Self Compacting Concrete(SCC)was prepared.The influencing mechanisms of water-binder ratio and anti-cracking agent on the workability,mechanical properties,volumetric deformation performance,and durability of fine stone SCC,such as resistance to sulfate erosion,chloride ion penetration,freeze-thaw,and carbonation,were investigated,and the performance change laws of fine stone concrete were also explored.The influence of different factors on the microstructure of concrete was investigated by Scanning Electron Microscope(SEM)and Nuclear Magnetic Resonance Spectroscopy(NMR)tests,and compared with the macroscopic properties.The results show that the water-binder ratio on the performance of fine stone concrete is similar to that of ordinary concrete.There is an optimum amount of anti-cracking agent,and the right amount of anti-cracking agent can generate Mg(OH),to fill matrix pores,which staggered grows with flocculent C-S-H and acicular AFt,improving the pore structure.It can also improve the mechanical properties and durability of fine stone concrete.However,when the dosage of the anti-cracking agent is too high,the compound erosion effect decreases the sulfate resistance of SCC,and the optimum content is 8%.
作者
何越骁
黄维蓉
唐喜
陈义林
汪子淇
HE Yuexiao;HUANG Weirong;TANG Xi;CHEN Yilin;WANG Ziqi(School of Civil Engineering,Chongqing Jiaotong University,Chongqing 400074,China;School of Material Science and Engineering,Chongqing Jiaotong University,Chongqing 400074,China)
出处
《湖南大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2023年第12期92-101,共10页
Journal of Hunan University:Natural Sciences
基金
广西重点研发计划项目(桂科AB22036007)
材料与化工重庆市研究生联合培养基地基金(JDLHPYJD2019002)
重庆交通大学研究生科研创新(创新基金)项目(CY820297)。
关键词
自密实混凝土
细石混凝土
耐久性能
抗裂剂
self-compacting concrete
fine stone concrete
durability
anti-cracking agent
作者简介
通信联系人:何越骁(1997-),男,重庆人,重庆交通大学博士研究生,E-mail:1269716582@qq.com。
