Grab bucket dredging is suitable for excavating medium and small river channels with large mud layer thickness and many obstacles in the construction area and is mostly used for dredging projects with enlarged flood discharge sections. Grab dredger flexible, not affected by the river garbage, stones and other obstacles, suitable for the excavation of hard earth or entrap more impurities of the earth garbage: and the construction process is simple, equipment is easy to organize, the project investment is more provincial, the construction process is not affected by the weather. But the grab dredger is very weak sediment sensitivity is poor, the excavation is easy to produce "dig the bottom of the bed of the hard stratum earthwork, so as to leak a lot of surface mud, especially floating mud": easy to cause the surface floating mud back to the water body after agitation. The silt removal rate of grab bucket dredging can only reach about 30%, and the grab bucket dredging is easy to cause floating mud omission and strong disturbance of bottom mud, so it is relatively seldom used in dredging projects aimed at improving water quality and is mainly used in dredging of various basins, docks, and channels.
