现场喷射成型双掺硅粉和钢纤维湿喷混凝土弯曲韧性研究  

On-site flexural toughness of wet-sprayed concrete with silica fume and steel fibers

作　　者：程伟峰 杨虹 仝德华 张鹏 丁建彤[4] 李海达[4] CHENG Weifeng;YANG Hong;TONG Dehua;ZHANG Peng;DING Jiantong;LI Haida(Power China Kunming Engineering Corporation Limited,Kunming 650033,China;China Power Construction Group Municipal Planning and Design Institute Co.,Ltd.,Zhuhai 519000,China;Yalong River Hydropower Development Co.,Ltd.,Chengdu 610051,China;Power China Sinohydro Bureau 7 Co.,Ltd.,Chengdu 610213,China)

机构地区：[1]中国电建集团昆明勘测设计研究院有限公司,云南昆明650033 [2]中国电建集团市政规划设计研究院有限公司,广东珠海519000 [3]雅砻江流域水电开发有限公司,四川成都610051 [4]中国水利水电第七工程局有限公司,四川成都610213

出　　处：《岩土工程学报》2025年第5期1073-1081,共9页Chinese Journal of Geotechnical Engineering

摘　　要：针对强岩爆、高突涌水、高地应力硐室,采用弓形排状新型钢纤维、新型液态无碱速凝剂、大型湿喷台车+机械臂及钢纤维新型添加工艺系统开展了掺硅粉及钢纤维湿喷混凝土的现场弯曲韧性试验研究。这种能够真实反应湿喷混凝土现场附着硬化性能的大规模生产性试验研究在中国尚属首次。结果表明:随着硅粉和钢纤维的掺入,附着硬化后的湿喷混凝土初裂荷载和极限荷载提高,弯曲韧性指数、承载能力变化系数及残余强度因子明显改善,开裂后未发生脆性断裂,峰值荷载后的承载力下降缓慢,且作用效果随着纤维掺量的增加而增强,其中40 kg掺量下荷载-挠度曲线有二次硬化现象,材料去脆性化迹象明显,抑制围岩破坏和与围岩同步变形能力得到增强。For the cavern with of rockburst,water gushing and high geostress,the researches on the on-site flexural toughness properties of the wet-sprayed concrete containing silica fume(SF)and reinforced by steel fibers are carried out to investigate the effects of steel fiber content and SF on flexural toughness index and the difference from the plain concrete.The SF is added according to 10%of the cement mass,two mass contents of steel fiber(35,40 kg/m3)are considered in this study,and large wet spraying machine is used.The concrete specimens used in the flexural toughness experiments are formed in site,which contain accelerator of 8%.It is the first time in China that the large-scale productive experiments adopt a large number of new technologies and can truly reflect the on-site adhesion and hardening properties of the wet sprayed concrete.Through the collaborative participation of 10 institutions,the experiments are successfully completed,and the effective results are achieved.It is indicated that the crack load and the ultimate load of concrete increased,the flexural toughness is improved when the SF and steel fiber are added,and the flexural toughness index increases with the increment of the steel fiber.Especially,the load-deflection curves show the peak of the secondary hardening of shotcrete with steel fiber content of 40 kg,which means the better resistance deformation capacity and increased residual strength.So the steel fiber reinforced wet-sprayed concrete containing the SF can enhance its toughness and the capability of resisting crack and improve its brittleness characteristic.

关 键 词：硅粉 钢纤维 湿喷混凝土 现场弯曲韧性 喷射成型 大型湿喷台车 

分 类 号：TU43[建筑科学—岩土工程]