This is accomplished by grouting the voids of blocks containing rebar with concrete. Grouting and patching may be required to fill any voids, holes, cracks or imperfections. Conventional drilling and grouting methods are used for this method of underpinning. Methods for introducing polymers into soils include mixing, injection, spraying, and grouting. Use of micropiles and jet grouting are common methods in underpinning. Secondly, partial grouting of hob beam joints reduced resilience to movement and pressure. After the disaster grouting of the cracks was done. These structures are filled with steel cables and protective grouting or grease. The most diffused techniques are the jet grouting technique and the pile work technique. After a second grouting and refill operation, the embankment was deemed leak-free. The greatest use of pressure grouting is to improve geomaterials (soil and rock). Phase two, which includes grouting the dam's foundation, began in January 2007. Later the land was stabilized by grouting and the unsafe buildings were pulled down. Curtain grouting was used in an effort to remedy this. Some further grouting works and replacement of the lock gates took place in the 1970s.