岩溶地层运营期地下水上涨引起管片上浮规律研究

岩溶地层溶隙发育，地下水流通性强，盾构隧道施工过程中浆液易流失，导致隧道运营过程中易出现上浮错台等灾害。为了研究岩溶地层盾构隧道在运营期因地下水位变化造成的管片上浮问题，通过数值模拟和现场监测，分析岩溶地层盾构隧道在运营期因地下水位上涨引起管片上浮的规律。结果表明：注浆层隧顶空洞、隧底注浆不密实和地下水位上涨是影响管片上浮的主要因素，其中隧顶空洞对管片上浮影响最大；管片隧顶注浆流失越严重，上部注浆层对管片的约束越小，地下水位上涨造成的管片上浮越明显；管片隧底注浆不密实导致管片底部和注浆层之间粘结力降低，管片上浮量增加；研究给出了管片上浮量与注浆层空洞、注浆不密实和地下水位的对应关系，可为岩溶地层盾构注浆施工质量控制提供借鉴。

Floating Law of Pipe Segments Caused by the Rise of Groundwater during Karst Formation Operation

Karst formation has developed gaps, groundwater circulation is strong, and slurry is easy to lose during shield tunnel construction, resulting in disasters such as floating and wrong platform during tunnel operation. In order to study the problem of segment floating caused by the change of groundwater level during the operation period of karst shield tunnel, the law of segment floating caused by the rise of groundwater level during operation period of karst shield tunnel was analyzed through numerical simulation and on-site monitoring. The results show that the top cavity of the grouting layer tunnel, the uncompactness of the bottom grouting and the rise of the groundwater level are the main factors affecting the floating of the segment, and the tunnel top cavity has the greatest influence on the floating of the segment. The more serious the grouting loss at the top of the segment tunnel, the smaller the constraint of the upper grouting layer on the segment, and the more obvious the floating of the segment caused by the rise of the groundwater table. The grouting at the bottom of the segment tunnel is not compact, resulting in a decrease in the adhesion between the bottom of the segment and the grouting layer, and an increase in the float on the segment. The correspondence between the floating amount of the segment and the void of the grouting layer, the uncompactness of the grouting layer and the groundwater table is given, which can provide reference for the quality control of shield grouting construction in karst formation.