低回弹高早强喷射混凝土技术与工程应用  

Technology and Engineering Application of Shotcrete with Low Rebound and High Early Strength

作　　者：王家赫 谢永江 冯仲伟 谭盐宾 李化建 李享涛 仲新华 WANG Jia-he;XIE Yong-jiang;FENG Zhong-wei;TAN Yan-bin;LI Hua-jian;LI Xiang-tao;ZHONG Xin-hua(China Academy of Railway Sciences Corporation Limited,Railway Engineering Research Institution,Beijing 100081,China;State Key Laboratory for Track Technology of High-speed Railway,Beijing 100081,China)

机构地区：[1]中国铁道科学研究院集团有限公司铁道建筑研究所,北京100081 [2]高速铁路轨道技术国家重点实验室,北京100081

出　　处：《混凝土与水泥制品》2023年第2期5-9,共5页China Concrete and Cement Products

基　　金：国家自然科学基金项目(51908550);中国铁道科学研究院集团有限公司科研项目(2021YJ173)。

摘　　要：为降低喷射混凝土施工回弹率、提高其早期力学性能和长期耐久性能,结合铁路隧道复合式衬砌结构体系对喷射混凝土的性能要求,研发了喷射混凝土用功能材料,并提出低回弹高早强喷射混凝土制备技术。通过试验室试验和工程应用案例,验证了该功能材料配制技术的可行性和使用效果。试验室试验结果表明:喷射混凝土的施工回弹率与其流变参数密切相关,所研发的功能材料与速凝剂复掺可显著提高喷射混凝土的早期力学性能和耐久性能,并降低施工回弹率。工程应用结果表明:采用本文提出的技术后,所制备的隧道初支喷射混凝土的施工回弹率≤10%,喷射混凝土8 h抗压强度≥10 MPa,24 h抗压强度≥15 MPa,56 d电通量<1200 C,满足隧道高性能混凝土的施工要求。In order to reduce the rebound rate of shotcrete construction,improve the early mechanical properties and long-term durability,combined with the performance requirements of the composite lining structure system of railway tunnels for shotcrete,functional materials for shotcrete were developed,and the preparation technology of low rebound and high early strength shotcrete was proposed.The feasibility and application effect of the preparation technology of functional materials were verified through laboratory and engineering applications.The laboratory test results show that the rebound rate of shotcrete construction is closely related to its rheological parameters.The developed functional materials and accelerator can significantly improve the early mechanical properties and long-term durability of shotcrete,and reduce the construction rebound rate.The engineering application results show that after adopting the technologies proposed,the construction rebound rate of shotcrete for initial tunnel support is≤10%,the compressive strength of shotcrete for 8 h is≥10 MPa,the compressive strength for 24 h is≥15 MPa,and the 56 d electric flux is<1200 C,which can meet the construction requirements of tunnel high-performance concrete.

关 键 词：喷射混凝土 低回弹 高早强 力学性能 耐久性能 

分 类 号：TU528.53[建筑科学—建筑技术科学]