Abstract: Karstic sinkhole will cause huge potential safety hazards to surrounding structures, and grouting technology is a very effective mitigation method. When a single collapse is encountered, the construction operations should be stopped immediately, and the collapse site should be backfilled with clay. Then the scope and nature of sinkhole should be analyzed, the original design should be modified accordingly. Then the collapse site should be grouted. Several key technoogies for grouting treatment of collapse are as follows: first, grouting pressure should not be too high; secondly, grouting should follow the principle of surrounding first and then center area; finally, the standard of grouting final hole should be controlled according to grouting test condition and grouting rate. In this paper, the application of grouting technology in a karstic sinkhole treatment project is studied, which provides a good reference for similar projects.

Key words: karstic sinkholes； grouting, grouting pressure； termination of grouting standard