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In focus is improvement of hole-making technology by vibro hammer pushing with batch-wise removal of soil core while a pipe is driven in soil under impact loading. The important advantage of the technology is the concurrent pipe driving and soil core removal. The minimal air pressure required to separate a core and transport it along the pipe is determined. The frequency of soil core separation and transport during vibro-hammer driving of pipes in soil has been tested in underground construction of utilities. The tests prove the possibility to cut-down time of trenchless construction of underground passages and to raise the level of mechanization of the operations.

Two approaches are set forth to explain the sense of the process of soil core self-discharging from a pipe under the action of impact load generating anomalously low friction and oncoming pressure on the core. Some objects are stated for further experimental investigations.

The disadvantages of devices for cyclic cleanup of a pipe from soil core during trenchless underground pipeline laying are shown. Three variants of the cleanup device movement towards the borehole bottom are analyzed. The methods are proposed for increase in haulage velocity.