地铁盾构管片用高性能混凝土性能研究  

Research into the Performance of the High-Performance Concrete for Subway Shield Segments

作　　者：权军力 QUAN Junli(The Fourth Engineering Co. Ltd. of the 18 Bureau Group of China Railway, Tianjin 300350, China)

机构地区：[1]中铁十八局集团第四工程有限公司,天津300350

出　　处：《国防交通工程与技术》2021年第1期80-83,共4页Traffic Engineering and Technology for National Defence

摘　　要：为了解决地铁盾构管片施工过程中渗水问题,研究立足于天津地铁项目,综合现有高性能混凝土配合比的设计经验,采用控制变量的方法,设计出配合比C1、C2、C3。通过对比3个配合比的工作性能、力学性能、电通量、氯离子扩散系数以及抗渗等级,得出相关结论如下:①C1配合比工作性评价劣于C2、C3,尤其是2 h坍落度、含气量的损失率均高于其他配合比;②56 d强度发展趋势为C3>C2>C1;③56 d标准养护条件下电通量、氯离子扩散系数发展趋势均为C1>C2>C3,抗渗等级发展趋势C3>C2>C1。C1配合比不满足管片用混凝土技术要求,C3配合比综合性能最优,应用于实际工程结构中。Aiming at solving the problem of water seepage during the construction of the subway shield segments,and being based on the Tianjin subway project,the research of ours synthesizes the existing design experience of high-performance concrete mix ratios,and adopts the method of controlled variables successfully to design mix ratios C1,C2,and C3.By comparing the workability,mechanical properties,electric flux,chloride ion diffusion coefficients and impermeability grades of the three mix ratos,the relevant conclusions we come to are as follows:①The workability evaluation of the C1 mixture ratio is inferior to C2 and C3,especially the lossrate of slump and gas content in 2 h are higher than those of other mix ratios;②The strength development trend of 56 d is C3>C2>C1;③The development trend of electric flux and chloride ion diffusion coefficient under the 56 d standard curing conditions is all C1>C2>C3,and the development trend of impermeability grade is C3>C2>C1.So the C1 mix ratio does not meet the technical requirements of the segment concrete,and the C3 mix ratio has the best comprehensive performance,which may be applied to practical engineering structures.

关 键 词：盾构管片 高性能混凝土 工作性能 力学性能 抗渗等级 

分 类 号：TU528[建筑科学—建筑技术科学]