Abstract
Widely applied in various projects, this method employs a dual-fluid, ultra-high pressure jet system mounted on an excavator typically used for pipe jacking and shield methods to shear and remove underground obstacles and for ground improvement. While the influences and range of the dual-fluid jets on the surrounding ground have been ascertained through empirical studies, difficulties in performing measurements during excavation have impeded efforts to date to clarify the range of such influences on nearby structures.
This paper attempts to clarify the characteristics of the dual-fluid jet demonstrated during ground excavation by measuring the jet's dynamic pressure and based on observations and FVM analysis (Finite Volume Method) of the excavation processes using a model of the ground. The paper offers numerical grounds for predicting the jet's influence range.
The study led to a number of conclusions: the jet's dynamic pressure immediately after it is injected from the nozzle falls short of the threshold pressure that would pose a risk of damage to nearby structures; the jet's ground excavation processes and flow characteristics within the excavation area can be accurately simulated via FVM analysis.
