Cir Array

The Cir Array is an instrument designed to monitor convergence and localised 3D deformation phenomena in tunnels under construction or existing. The Cir Array is a sequence of IP69 hermetic nodes joined together by a fibreglass rod to maintain alignment and a cable for data transmission. Each node contains a high-resolution 3D MEMS sensor and a thermometer. The instrument is customisable in terms of number and spacing between nodes and length, depending on the project requirements. The instrument can be managed by the A802, A301 controllers or by any other Datalogger compatible with the RS485 Modbus RTU protocol.

The instrument can be installed in a section of a tunnel under construction near the excavation face, in contact with the rock mass or on the preliminary lining, to monitor the deformations of the medium following excavation, or it can be placed on the defined lining to monitor the work in the operational phase. Installation is quick and easy. The instrument is supplied in segments which are then joined together using special connectors. Then, once the section to be monitored has been identified, the instrument can be attached to the work using special collars.

Knowing the distance between the nodes and their location, identified using the data recorded by the MEMS sensor, through special algorithms it is possible to identify the relative position of the instrument in space and consequently the deformation of the work.

  • Local displacements
  • Accumulated displacements
  • Local and cumulative displacements of calculation points over time
  • Acceleration and velocity of displacements at calculation points in time
  • Convergence segments
  • Node temperature over time
  • Equivalent area
  • Equivalent radius
  • Automatic deformation monitoring in near real-time
  • Data acquisition also during the excavation phases
  • Deformation reconstruction on multiple measuring points
  • Automatic alerting based on multi-level and multi-parameter thresholds
  • Automatic Monitoring Report

Correlated Product


  • Underground excavations
  • Mines

  • G802
  • G301