C30喷射混凝土力学与耐久性能研究  

Study on mechanics and durability of C30 shotcrete

作　　者：杨博凯 叶汉青 陈学义 Yang Bokai;Ye Hanqing;Chen Xueyi(Administration Office of Nanjing Yangtze River,Nanjing 210016,China)

机构地区：[1]南京市长江河道管理处,江苏南京210016

出　　处：《山西建筑》2023年第3期115-119,共5页Shanxi Architecture

摘　　要：喷射混凝土作为水工隧洞初期支护的核心材料,其力学性能和耐久性能优劣直接影响衬砌结构整体的稳定性。为充分了解C30喷射混凝土的实际服役水平,试验研究不同水灰比和速凝剂种类对C30喷射混凝土力学与耐久性能的影响,并与同配比模筑混凝土和C25喷射混凝土进行对比。试验结果表明:在水泥用量一定的情况下,随着水灰比的增大,C30喷射混凝土的力学与耐久性能均发生不同程度下降;无碱速凝剂相比有碱速凝剂对C30喷射混凝土的不利影响较小,后期强度保有率更高;同配比模筑混凝土的力学与耐久性能均明显优于喷射混凝土体系,C30喷射混凝土相比C25喷射混凝土性能提升显著,强度能够满足要求,但耐久性能仍处于相对较低的水平。Shotcrete is the core material for the primary support of hydraulic tunnels,and its mechanical properties and durability directly affect the overall stability of the lining structure.In order to fully understand the actual service level of C30 shotcrete,the effects of different water-cement ratio and accelerator types on the mechanical properties and durability of C30 shotcrete were tested and compared with molded concrete with the same mixing proportion and C25 shotcrete.The test results show that the mechanical properties and durability of C30 shotcrete decrease in varying degrees with the increase of water-cement ratio under the same cement content;compared with alkaline accelerator,alkali-free accelerator has less adverse effect on C30 shotcrete and higher strength retention rate in later stage;the mechanical properties and durability of the molded concrete with the same mixing proportion are obviously better than that of the shotcrete.The performance of C30 shotcrete is significantly improved compared with that of C25 shotcrete.The strength of C30 shotcrete can meet the requirements,but its durability is still at a relatively low level.

关 键 词：喷射混凝土 水工隧洞 力学性能 耐久性能 水灰比 速凝剂 模筑混凝土 

分 类 号：TU528[建筑科学—建筑技术科学]