抗裂降黏剂对硅粉抗冲磨混凝土性能提升研究  

Study on the improvement of the performance of silicon fume anti-abrasion concrete by anti-cracking viscosity reducer

作　　者：张丰[1,2] 李伟 陈刚[3] 祝烨然[1,4] 白银[1,2] ZHANG Feng;LI Wei;CHEN Gang;ZHU Yeran;BAI Yin(Nanjing Hydraulic Research Institute,Nanjing 210029,Jiangsu,China;State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering,Nanjing 210024,Jiangsu,China;Xinjiang Water Conservancy and Hydropower Survey Design Institute Co.,Ltd.,Urumqi 830000,Xinjiang,China;Nanjing R&D Hi-Tech Co.,Ltd.,Nanjing 210024,Jiangsu,China)

机构地区：[1]南京水利科学研究院,江苏南京210029 [2]水文水资源与水利工程科学国家重点实验室,江苏南京210029 [3]新疆水利水电勘测设计研究院有限责任公司,新疆乌鲁木齐830000 [4]南京瑞迪高新技术有限公司,江苏南京210024

出　　处：《水利水电技术（中英文）》2024年第10期186-196,共11页Water Resources and Hydropower Engineering

基　　金：国家重点研发计划(2020YFC1511902);国家自然基金重点项目(51739008);中央级公益性科研院所基本科研业务费专项资金项目(Y422008);新疆葛洲坝玉龙喀什水利枢纽开发有限公司科研项目资助(Hj423001)。

摘　　要：【目的】高强度硅粉混凝土普遍存在黏度高,施工难度大,开裂风险高等问题,严重影响泄水建筑物抗冲磨混凝土使用性能,因此抗冲磨混凝土设计要同时兼顾抗冲磨性能、施工性能和抗裂性能。【方法】前期通过复配膨胀组分、降黏组分和其他助剂研制了新型的混凝土抗裂降黏剂,以新疆某水利枢纽工程为对象,研究了抗裂降黏剂对不同强度等级硅粉抗冲磨混凝土的工作性、力学、变形、抗裂、抗冲磨等性能的影响,以综合评价其对硅粉抗冲磨混凝土性能改善效果。【结论】结果表明:抗裂降黏剂可用于配制C_(90)55、C_(90)50、C_(28)40不同强度等级的抗冲磨混凝土,且可显著改善硅粉抗冲磨混凝土的施工性能和抗裂性能。【结果】7%抗裂降黏剂的掺入,对混凝土坍落度、含气量、凝结时间影响不大,但可使C_(90)55、C_(90)50、C_(28)40硅粉混凝土拌合物塑性黏度减小64%~76%、屈服剪切应力减小26%~36%。相比于“硅粉”混凝土,“硅粉+抗裂降黏剂”混凝土收缩变形减小,至110 d龄期自生体积变形自始至终表现为“膨胀”,平板试验中单位面积上总开裂面积减小63%~83%,混凝土抗裂性能明显改善。此外,抗裂降黏剂的掺入,有利于提高混凝土内部密实度,可使混凝土抗压、抗拉强度略有提高,水下钢球法抗冲磨强度提高14%~40%。[Objective]High strength silica fume concrete generally has the problems of high viscosity,difficult construction and high cracking risk,which seriously affects the service performance of anti-abrasion concrete in discharge structures.Therefore,the design of anti-abrasion concrete should simultaneously consider anti-abrasion performance,construction performance and cracking resistance.[Methods]The authors have previously developed a new type of anti-cracking viscosity reducer for concrete by combining expansion components,viscosity reducing components and other additives.Taking a water conservancy project in Xinjiang as the object,the effects of anti-crack viscosity reducer on workability,mechanics,deformation,crack resistance,impact wear and other properties of different strength grades of silica fume concrete are studied.The effect of improving the performance of silica powder impact resistance concrete was evaluated comprehensively,in order to comprehensively evaluate its improvement effect on the performance of silicon powder anti-abrasion concrete.[Conclusion]The result show that the anti-cracking viscosity reducer can be used to prepare anti-abrasion concrete with different grades of C_(90)55,C_(90)50 and C_(28)40,and can significantly improve the construction performance and crack resistance of silicon fume anti-abrasion concrete.[Results]The addition of 7%anti-cracking viscosity reducer has little effect on slump,gas content and setting time of concrete,but can reduce the plastic viscosity of C_(90)55,C_(90)50,and C_(28)40 silica fume concrete by 64%to 76%,and the yield shear stress by 26%to 36%.Compared with silica fume concrete,the shrinkage deformation of concrete mixed with silica fume and anti-cracking viscosity reducer decreased,and the autogenous volume deformation was characterized by expansion throughout the 110 days,and the total cracking area per unit area in the plate test decreased by 63%to 83%.In addition,the incorporation of anti-cracking viscosity reducer was conducive to improve the inter

关 键 词：抗裂降黏剂 硅粉混凝土 抗冲磨性能 黏度 抗裂性能 变形 力学性能 

分 类 号：TV42[水利工程—水工结构工程]