Abstract: The groundwater cutoff curtain is one of the important aspects in the design of deep excavation supporting system. This paper introduces the type of cutoff curtains that applied in the deep excavation engineering; these types including: cement mixed soil columns, jet grouts, and pressure grout formed curtains. The major design parameters as well as the commonly encountered problems and their solutions in each type of the curtain are also introduced.

Key words: Cut-off Curtains, Deep Excavation Supporting System, Cement Mixed Soil Columns, Jet Grouts