摘要
盾构机在中间风井北端头水平冷冻法加固地层中二次始发掘进,因出土量突然增大,在停机处置期间,盾构机机体及刀盘被冻土捆住,并引发地面局部塌陷沉降。通过分析地面沉降和盾构机被冷冻土体冻结原因及冻结的具体部位,经充分讨论,对地面塌陷沉降区域,采取回填素混凝土充填塌陷孔洞,钻孔注浆挤密压实方法处理;对盾构机被冻结土体捆住问题,采用向刀盘前方和盾构机壳体外侧冻土层中注入热盐水融化冻土,向土仓中输入热蒸汽升高土仓中冻结土温度,向土仓、螺旋输送机内注入膨润土置换原冻土,地面实施监测等系列措施,盾构机成功解冻,恢复正常掘进。
The shield machine started its second excavation in the stratum reinforced by the horizontal freezing method at the north end of the middle air shaft.Due to the sudden increase of the excavated volume,the shield machine body and cutterhead were bound by frozen soil during shutdown and disposal,resulting in local ground collapse and settlement.Based on the analysis of the ground settlement and the freezing causes and specific parts of the frozen soil of the shield machine,the method of backfilling plain concrete to fill the collapsed holes,drilling grouting and compaction is adopted for the ground subsidence area after full discussion;For the problem that the shield machine is bound by frozen soil,a series of measures such as injecting hot salt water into the frozen soil layer in front of the cutterhead and on the outer side of the shield casing to melt the frozen soil,inputting hot steam into the earth bin to raise the temperature of frozen soil in the earth bin,injecting bentonite into the earth bin and screw conveyor to replace the original frozen soil,and monitoring the ground surface are adopted.The shield machine is thawed successfully and normal excavation is resumed.
作者
李迎春
周以东
季俊宇
白铁
LI Ying-chun;ZHOU Yi-dong;JI Jun-yu;BAI Tie(Wuxi Metro Group Co.,Ltd,Wuxi Jiangsu 214000 China;Jiangsu Suzhou Geological Engineering Survey Institute,Suzhou Jiangsu 215000 China;Jiangsu Guanjie Construction Group Co.,Ltd,Wuxi Jiangsu 214000China)
出处
《江苏建筑》
2021年第5期65-68,共4页
Jiangsu Construction
关键词
盾构
冷冻
沉降
受困
解冻
shield
freezing
subsidence
trapping
thawing
作者简介
李迎春,男(1972-),无锡地铁集团有限公司,正高级工程师,从事城市轨道交通行业工作。
