Recent advances in plasma arc technology have found many civil engineering applications, including in-situ soil vitrification (ISV). The ISV process transforms soils into homogeneous glass-like materials, which possess high compressive and tensile strengths (typically about 10 times those of unreinforced concrete), high leaching resistance, and are unaffected by wet-dry or freeze-thaw cycles. These vitrified earthen materials usually weigh about 2300 to 2500 kg per cubic meter. Potential ISV applications include slope stabilization, groundwater removal, subgrade stabilization, and simulated construction materials.
A 100-kW non-transferred plasma arc torch developed by the Plasma Energy Corporation was used for soil vitrification experiments with operating temperatures at about 4000°C. The soils tested include Piedmont silty sand, kaolin clay, and Tyndall beach sand. 5.1-cm cubes and 5.1-cm diameter cylinders were cut from the vitrified soil samples and subjected to compression tests, split-cylinder tension tests, and split-Hopkinson bar impact tests
