Diaphragm walls are one of the most important technologies of special foundation engineering. A diaphragm wall is constructed using a trench excavated in ground and supported by a mud fluids (typically bentonite or polimer mud) until the mud is replaced by concrete, after the steel cage installation. Walls generally range from 600 to 1500 mm thickness, in wide between 2000 and 3500 mm and can be excavated to depths of 60m or more.