METHOD AND DEVICE FOR PERFORMING GROUND TEST WITH THE USE OF SCREW PUNCH Russian patent published in 2005 - IPC

FIELD: construction, particularly engineering investigations to determine earth strength and deformation characteristics.

SUBSTANCE: method involves rotary driving hollow pipe string for the test depth with the use of boring rig so that minimal vertical load is applied to the pipe string. Pipe string is provided with screw punch blade having constant pitch and varying blade thickness which increases in down-top direction. Blade is provided with pressure transducers flushed with lower surface thereof. Pressure transducers are connected with original ground by communication cable. Module of deformation is determined with the use of well-known method by stabilized pressure value of each transducer after punch driving completion and from predetermined rate of deformation under each transducer. Rate between punch immersion depth per one turn h and pitch thereof a is synchronized up to obtaining value of h/a≤1.0 before reaching test depth for instance with the use of screw pair. Non-stabilized pressure values under each transducer are recorded immediately before punch driving stop.

EFFECT: increased measuring reliability and output.

5 cl, 1 dwg