摘要
在普通混凝土中掺入一定量的短钢纤维可改善和提高结构的整体性能。目前钢纤维混凝土已在地上结构得到了应用,但在滨海海相地层地铁盾构隧道中尚无应用案例,其相关技术指标与设计参数尚需进一步研究与完善。为此,文章依托深圳地铁西丽湖—西丽区间隧道工程,采用室内试验分析方法,针对海相地层地铁盾构隧道钢纤维混凝土管片开展研究,结果表明:(1)钢纤维对混凝土的各项强度有一定的增强与改善作用;(2)钢纤维的长度及最大粒径粗骨料的合理比率对提高混凝土管片抗折强度十分重要;(3)砂率的变动对拌和料的和易性能产生较大的影响;(4)钢纤维存在一个合理的掺入量;(5)钢纤维使纤维混凝土的微裂缝减少,孔隙结构得到改善,从而提高了管片的抗渗性能。
The structural performance will be improved if certain amount of short steel fibers are added into the or? dinary concrete. The steel fiber reinforced concrete has been applied in the above-ground structure but there is no application case in metro shield tunnels in marine stratum by the sea, so the relevant technical indexes and design parameters should be further studied and perfected. Based on the Xilihu-Xili running tunnel of Shenzhen metro, a study on steel fiber reinforced concrete segment of metro shield tunnel in marine stratum was conducted by laboratory test, and the results show that: 1) various kinds of strengths of concrete are improved attributed to steel fibers;2)it is significant to have reasonable steel fiber length and reasonable proportion of course aggregates with maximum grain size to improve the flexural strength of concrete segment;3) sand ratio change has significant effect on workability of mixture;4) the proportion of steel fibers should be reasonable;5) the micro-crack of fiber reinforced concrete is reduced, the pore structure is improved and the permeability of segment is improved thanks to steel fibers.
作者
郑爱元
徐斌
陈湘生
ZHENG Aiyuan;XU Bin;CHEN Xiangsheng(Shenzhen Metro Group Co., Ltd., Shenzhen 518026;China Railway Academy Co., Ltd., Chengdu 610031)
出处
《现代隧道技术》
EI
CSCD
北大核心
2019年第5期211-217,共7页
Modern Tunnelling Technology
关键词
海相地层
地铁
盾构隧道
钢纤维混凝土管片
试验
性能研究
Marine stratum
Metro
Shield tunnel
Steel fiber reinforced concrete segment
Test
Performance study
