Goodman Jack

Applications

The Goodman Jack is a borehole tool used for estimating the deformability of rock masses in-situ. It is designed to be used in 3″ (76 mm) boreholes.

Two models are available: a twelve piston model for use in hard rock, and a three-piston model for determining the consolidation-time properties of soft rock, soil, and stiff clays.

Goodman Jack

Operation

The Goodman Jack consists of a hydraulic jack with curved bearing plates, LVDT sensors, a displacement indicator, a hydraulic pump with a pressure gauge, a hydraulic hose, an electrical cable, and a coupler for drill rods.

The jack is attached to the drill rod and inserted into the borehole. A hand pump is used to create hydraulic pressure in the lines connected to the jack, which in turn activates the pistons and produces a uniform and unidirectional stress field at the bearing plate. The applied hydraulic pressure is measured with a standard Bourdon-type pressure gauge. The deformation of the rock is measured by two linear variable differential transformers (LVDT) and data are displayed by the indicator at the surface. After the test, the bearing plates are retracted by reversed pistons, and the jack is withdrawn from the borehole.

The modulus of deformation is calculated using formulae derived empirically from in-situ testing and correction factors that were developed by laboratory testing.

For more information

Please download the datasheet and manual for the Goodman Jack. It can be viewed and printed with Adobe Acrobat Reader.

Goodman Jack Specifications

HARD ROCK JACK
Number of Pistons12
Max Bearing Pressure64,000 kPa (9,300 psi)
Maximum Force703 kN (158,100 lbf)
Borehole Size76 mm, 3" nominal
Minimum Diameter70 mm (2.75")
Maximum Diameter83 mm (3.25")
Linearity±0.5% for range of 73.7 to 78.7 mm (2.9 to 3.1"), ±1% for range of 72.4 to 80 mm (2.875 to 3.15")
Maximum Hydraulic Pressure69,000 kPa (10,000 psi)
Operating Temp-32 to 60 °C (-25 to 140 °F)
Temp. Coefficient±(0.04% Reading + 0.02% FS) per °C.
±(0.02% Reading + 0.01% FS) per °F
Dimensions70 x 445 mm (2.75 x 17.5")
Weight15 kg (33 lb)
SOFT ROCK JACK
Number of Pistons3
Max Bearing Pressure38,200 kPa (5,540 psi)
Maximum Force419 kN (94,200 lbf)
Borehole Size76mm, 3" nominal
Minimum Diameter70 mm (2.75")
Maximum Diameter83 mm (3.25")
Linearity±0.5% for range of 73.7 to 78.7 mm (2.9 to 3.1"), ±1% for range of 72.4 to 80 mm (2.875 to 3.15")
Maximum Hydraulic Pressure69,000 kPa (10,000 psi)
Operating Temp-32 to 60 °C (-25 to 140 °F)
Temp. Coefficient±(0.04% Reading + 0.02% FS) per °C.
±(0.02% Reading + 0.01% FS) per °F
Dimensions70 x 445 mm (2.75 x 17.5")
Weight15 kg (33 lb)
DISPLACEMENT INDICATOR
DisplayDual LCDs with 3-digit signed values
Operating Time10 hours with fully charged batteries
Battery ChargerInternal from 115/230 VAC or 10-15 VDC
Temp. Coefficient±(0.015% Reading +0.001% F.S.) per °C.
±(0.008% Reading +0.0006% F.S.) per °F.
Operating Temp-18 to 49°C (0 to 120 °F)
Resolution0.01 mm with Metric Indicator.
0.001" with English Indicator
Dimensions280 x 230 x 180 mm (11 x 9 x 7")
Weight5 kg (11 lb)
HAND PUMP
Hydraulic PumpEnerpac P-84
Maximum Pressure69,000 kPa 10,000 psi
Pressure Gauge50 psi (345 kPa) resolution with accuracy of ±0.5% FS
Dimensions690 x 180 x 150 mm (27 x 7 x 6")
Weight13 kg (29 lb). Hose and cable add 10 kg per 15 m (22 lb per 50’)
PART NUMBERS
Goodman Jack, Hard Rock52100100Hydraulic borehole probe for in situ tests in hard rock. Includes two LVDT displacement transducers, waterproof electrical connector, two self-sealing hydraulic quick-connectors, and threaded BX adapter
Goodman Jack, Soft Rock52100200Hydraulic borehole probe for in situ tests in soft rock. Includes two LVDT displacement transducers, waterproof electrical connector, two self-sealing hydraulic quick-connectors, and threaded BX adapter
Displacement IndicatorEnglish Unit52102700
Metric Unit52102710
Electrical Cable Assembly52100500Shielded, multi-conductor cable, waterproof connectors
on each end, 15 m (50’)
Hydraulic Hose Assembly52100600High Pressure Hydraulic Hose, 1/4-inch (6.4 mm.) I.D., double steel wire braid, SAE 100R2 Type A, with self-sealing quick-connectors each end, 50 ft (15 m)
Hydraulic Pump, Model P-8452100700Two-stage, 10,000 psi (70 MPa), with selector valve
Hydraulic Tee Assembly52100800Includes three self-sealing quick-connectors for easily connecting hydraulic hose, pressure gauge and hydraulic pump
Pressure Gauge, Model 20052100900Bourdon-type, 4.5" diameter gauge with accuracy of 0.5% and twin tip pointer to eliminate reading errors. Range: 10,000 psi (70 MPa). Other ranges available on request
Hydraulic Oil, HF-10152102400Note: Carriers require surcharge and separate documents for air shipments of hydraulic oil
Carrying Case, For Jack52101500Wooden carrying case for shipping and storage of Goodman Jack and accessories
Carrying Case, For Pump52101501Wooden carrying case for shipping and storage of pump and accessories