摘要
为分析大直径盾构隧道纵向连接发展规律,以济南黄河隧道工程为依托,设计管片足尺试验,通过环缝错台量-剪轴比关系及螺栓应变-剪轴比关系,研究大直径盾构隧道(外径15.2 m)环缝接头剪切变形规律及螺栓应变变化规律。根据试验结果,将环缝剪切划分为4个阶段:摩擦阶段(剪轴比0~0.17)、间隙闭合阶段(螺栓顺剪0.17~0.88,螺栓逆剪0.17~0.67)、强化阶段(螺栓顺剪0.88~,螺栓逆剪0.67~0.98)及破坏阶段(螺栓逆减0.98~)。结果表明,逆剪螺栓接头较顺剪螺栓接头更早进入强化阶段,逆剪螺栓接头的破坏剪轴比约为0.98;螺栓逆剪工况接头的抗剪效果低于螺栓顺剪工况,建议施工中错台量宜取12 mm作为控制指标;环缝错台曲线与螺栓应变曲线斜率变化时剪轴比具有一致性,验证了上述各阶段划分的合理性;根据螺栓各应变测点应变发展情况,明确了逆剪螺栓塑性区位置。
In order to analyze the development law of the longitudinal connection of large diameter shield tunnel,a full-scale test of the segment is designed based on the Jinan Yellow River Tunnel Project.The shear deformation law and bolt strain variation law of circumferential joints in the large diameter shield tunnel(outer diameter 15.2 m)are studied based on the relationship between the amount of annular joint dislocation and shear axial ratio,the relationship between bolt strain and shear axial ratio.According to test results,the process of circumferential joints shear can be divided into four phases:friction phase(shear axis ratio 0~0.17),gap closure phase(bolt straight shear 0.17~0.88,bolt reverse shear 0.17~0.67),strengthening phase(bolt straight shear 0.88~,bolt reverse shear 0.67~0.98)and failure stage(bolt reverse reduction 0.98~).Compared with the parallel shear state,the bolt bearing the reverse shear force enters the strengthening stage earlier and the failure shear axial ratio of the reverse shear bolted joint is about 0.98.The shear effect of the bolt joint under the reverse shear condition is lower than that of the bolt ordinal shear.It is suggested that the amount of misalignment in construction should be 12mm as the control index.The shear-axis ratios are consistent whenthe slope of the circumferential joints stagger curve and the bolt strain curve changes,which verifies the rationality of the division of the above phases.According to the strain development of each strain measuring point of the bolt,the plastic zone position of the reverse shear bolt is identified.
作者
田应飞
李明宇
陈健
曾力
历朋林
李春林
余刘成
TIAN Yingfei;LI Mingyu;CHEN Jian;ZENG Li;LI Penglin;LI Chunlin;YU Liucheng(School of Civil Engineering,Zhengzhou University,Zhengzhou 450001,China;China Railway 14th Bureau Group Co.,Ltd.,Jinan 250101,China;China Railway 14th Bureau Group Shield Engineering Co.,Ltd.,Nanjing 211800,China;Jinan City Tunnel Construction Group Co.,Ltd.,Jinan 250000,China)
出处
《铁道标准设计》
北大核心
2022年第11期135-141,共7页
Railway Standard Design
基金
国家自然科学基金项目(51508520)
河南省重点研发与推广专项(科技攻关)项目(202102310586)
河南省住房城乡建设科技计划项目(K1940,K1817)。
关键词
盾构隧道
大直径盾构
斜螺栓-凹凸榫
环缝错台量
足尺试验
环缝接头
抗剪加载试验
shield tunnel
large diameter shield
oblique bolt-concave tenon
circumferential dislocation
full-scale test
circumferential joints
shear loading test
