An explosive subsoiler was envisaged and designed to achieve greater soil r
upture volume and longer sustainability of drainage for the improvement of
meadow soil. In this paper, the results are presented from soil bin experim
ents with the explosive subsoiler, that were conducted in Japan prior to fi
eld 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 pres
sure of about 6 kPa was produced at the nozzle port, a cavity was formed un
derground, 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 t
he 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 so
il disturbance. (C) 2000 Silsoe Research Institute.