CSIRO Hollow Inclusion Cell Rock Stress Sensor

The Hollow Inclusion Cell (HI Cell) rock stress sensor is an extremely precise geotechnical instrument specifically designed for in-situ monitoring of 3D triaxial rock stress.


  • CSIRO Strain Cell design
  • Australian made
  • Analogue output
  • Digital output
  • Compatible with a wide range of dataloggers


Hollow-inclusion Cell Rock Stress Sensor

HI Cell rock stress sensor can be used for overcoring applications where it’s used to determine absolute stress magnitude and orientation. It’s often installed and left in-situ for long-term monitoring where relative changes of stress can be observed.

Digitising the sensor has made it easy to monitor with modern loggers. The serial output can be read by nearly all big brands of loggers meaning the user can choose any logger they want without being tied to a particular brand. The convenience of making it digital has improved accuracy and the ability to add more sensors such as orientation and temperature.

HI Cells can be permanently fixed within a borehole to provide real-time indications of strain and temperature. Since it was developed in the 1980’s the CSIRO HI Cell has been a bench mark for over 40 years and still remains the sensor of choice for many geomechanics and rock mechanics experts.

CSIRO Strain Cell

Geosystems HI Cells are based on the original CSIRO design but with upgraded features and digitisation that eliminate the need for expensive multi-strand cables or very expensive strain monitors. We are constantly developing and improving the design making Geosystems the best one-stop-shop for 3D in-situ stress measurement instruments and systems.

We offer an end-to-end solution that begins with the sensor and ends with analysis software, one simply inputs data and follows the calculation procedure to obtain a result. Unlike our competitors, we provide you with all the tools to undertake a successful campaign. We can provide field services where needed but also have the flexibility to sell the system to anyone interested in doing it themselves.


Digital Hollow Inclusion (HID) Cell

The HID Cell is a highly accurate rock stress sensor that is built upon the analogue Hollow Inclusion Cell (HI Cell).

Designed to be permanently fixed within a borehole, the HID Cell digitises the strain measured at the gauges, rather than at the end of a multi-strand cable. Consequently, the signal is not degraded and no special loggers are needed.

The serial output can be sent to either a computer, laptop, or logger as required.

Geosystems can supply low-cost data loggers capable of acquiring real-time data from up to four HID Cells. The data is saved to a simple CSV file on a USB stick or we have simply plug and play Bluetooth loggers that are easily networked. The network can


Hollow Inclusion HI Cell – Analogue

The Geosystems Hollow Inclusion (HI) Cell reliably and accurately determines the triaxial stress in rock and concrete. it is suitable for boreholes in tunnels and other structures.

The HI Cell analogue rock stress sensor required a strain bridge to monitor the read values. We usually advise the use of our digital HI Cell that uses a breakout box and tablet for data logging.

Over 30 years of industry experience in rock mechanics and Geotechnical instruments.


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