An Explosive Subsoiler for the Improvement of Meadow Soil, Part 2: Soil Bin Experiments

An explosive subsoiler was envisaged and designed to achieve greater soil rupture volume and longer sustainability of drainage for the improvement of meadow soil. In this paper, the results are presented from soil bin experiments with the explosive subsoiler, that were conducted in Japan prior to field experiments in China, to investigate soil rupture volume. The results showed that the sand and pseudogley soil were broken down by a moving subsoiler with gas injection. With a gas flow rate of 10 g/s, a pressure of about 6 kPa was produced at the nozzle port, a cavity was formed underground, and the subsoil was disturbed. Both forward and lateral rupture distances were constant, regardless of the differences in the soil and the gas flow rate. Hence, the average forward rupture distance was 0·75 m and the average lateral rupture distance was 0·25 m. Both values were influenced by the shape of the subsoiler body. Only 13% of the power required for gas injection was used in cavity formation, while the remaining 87% induced soil disturbance.