Tunnelling-induced ground settlements in a groundwater drawdown environment – A case history

摘要: Abstract In this paper a case history of conventional tunnelling in which tunnelling-induced groundwater drawdown caused excessive surface settlements is presented. The measured ground were first analyzed to identify the settlement characteristics at site relation drawdown. data revealed considerably larger affected zone than for cases with no drawdown, tendency slow stabilization. Also piezometric that significant portion total around 65%, was completed prior top heading arrival. This suggests pre-grouting paramount importance controlling inflow situations highly permeable water bearing ground. addition three-dimensional stress–pore pressure coupled finite element analysis performed confirmed direct link between and settlements. practical implications findings from study are also further discussed.