Plugging and Emergency Treatment Technology for Ultra Deep Foundation Excavation Karst Super Large Water Inrush
When excavating ultra deep foundation excavations in karst areas,when the karst burial depth is small and the groundwater is abundant,the foundation excavations are prone to dangerous situations such as bottom water inrush,mud gushing,sand gushing,etc.In severe cases,it can cause the foundation excavation to collapse,directly affecting the safety of the surrounding environment.In complex geological conditions,karst development,large water inrush and emergency situations,the conventional plugging and emergency treatment method of peripheral curtain grouting combined with internal water inrush point backpressure plugging is slow to take effect,time-consuming and costly.The water inrush cannot be quickly plugged,and the danger cannot be quickly eliminated.For this purpose,in conjunction with the emergency rescue project for the 1 000m3/h super large water inrush at the bottom of the 35m deep foundation excavation of the Guangzhou comprehensive transportation hub subway station,the two-shot grouting two-layer pockets internal plugging technology was adopted to directly drill and inject grout to plug the water inrush point in the foundation excavation.The pockets were used to ensure that the double liquid slurry could solidify quickly.The first layer pocket was used to plug the drill hole and water inrush points,and the second layer pocket was used to plug the karst holes,cracks,etc.next to the drill hole.The upper and lower pockets complemented each other,and two-shot grouting was used to plug the bottom of the cave to prevent the loss of slurry.Engineering practice shows that the two-shot grouting two-layer pockets internal plugging technology is easy to operate,direct,fast,and highly targeted when plugging with large water inrush and high water pressure karst in foundation excavations,which can achieve the goal of rapid and effective grouting and emergency treatment.
foundation excavationkarstwater inrushtwo-shot groutingpocketpluggingtreatment
万方数据
维普
