StrainTrack – Automated strain monitoring kit

Overview

The StrainTrack is a automated solution designed for the measurement and continuous monitoring of mechanical strain on structures, civil engineering works and industrial equipment.

The system combines one or more strain gauges, an acquisition unit dedicated to Wheatstone bridges and transmission to a remote supervision platform.

The sensors are installed directly on the structure to be monitored in order to measure the very small dimensional variations caused by:

• applied loads
• pressure variations
• mechanical forces
• operating cycles
• thermal variations
• progressive deformation of the structure

Data is automatically recorded and then transmitted to PMI-CloudVIEW, where it can be viewed as curves, historical data and alert indicators.

Monitored quantities

The StrainTrack makes it possible in particular to monitor:

• longitudinal strain
• compression strain
• tension strain
• structural evolution under load
• cyclic strain variations
• behavioral differences between several instrumented zones
• slow drift over time
• overload events
• thermal effects on the structure

Depending on the type of structure and the available mechanical parameters, strain measurements can also be used to estimate mechanical stresses.

Kit composition

The StrainTrack system may include:

• one or more strain gauges
• bonded strain gauges
• screwed strain gauges
• welded strain gauges
• mounting accessories
• cables and connectors
• an acquisition node for Wheatstone bridges
• a temperature measurement depending on the configuration
• an IoT gateway or communication
• a power supply suited to the site
• the PMI-CloudVIEW platform
• the protection accessories required for installation

The number of sensors, their technology and their placement are defined according to the structure and the zones to be monitored.

Bonded strain gauges

Bonded strain gauges are fixed directly onto the prepared surface of the structure.

They allow precise measurement of small strain variations on:

• metal beams
• frames
• pillars
• mechanical components
• tanks
• metal structures
• industrial equipment

This technology enables compact instrumentation with minimal influence on the mechanical behavior of the structure.

Appropriate surface preparation and sensor protection are necessary to guarantee long-term measurement stability.

Screwed strain gauges

Screwed strain gauges allow a robust mechanical installation on the structure.

They are particularly suitable when:

• bonding is not desired
• the installation must be removable
• the structure is exposed to severe industrial conditions
• a quick installation is required
• the sensor requires reinforced mechanical protection

They can in particular be used on:

• metal structures
• beams
• frames
• machines
• silos
• tanks
• industrial works

Acquisition and transmission

The StrainTrack node automatically handles the acquisition of the strain gauges installed on the structure.

Depending on the configuration, it can manage several measurement points in order to simultaneously compare different zones.

The system can provide:

• excitation of the Wheatstone bridges
• measurement acquisition
• offset compensation
• local recording
• time-stamping
• temperature measurement
• periodic transmission
• data retention in case of network loss
• retransmission upon restoration of communication

The measurement and transmission frequency is adapted to the behavior of the structure and the objectives of the project.

Thresholds and alerts

Thresholds can be configured to automatically detect abnormal evolution.

The system can in particular generate an alert in case of:

• excessive strain
• rapid evolution
• exceeding a predefined value
• significant difference between several zones
• unusual variation compared to the reference state

Thresholds are defined according to the structure, the application and the project criteria.

Applications

The StrainTrack can be used for:

• beam monitoring
• metal frame monitoring
• bridge monitoring
• footbridge monitoring
• pillar monitoring
• industrial structure monitoring
• silo monitoring
• tank monitoring
• reservoir monitoring
• building monitoring
• monitoring of structures under load
• control of temporary structures
• industrial machine monitoring
• load testing
• civil engineering structure monitoring
• metal structure monitoring
• temporary or permanent instrumentation

Advantages

• continuous strain monitoring
• measurement directly on the structure
• bonded or screwed strain gauges
• installation adaptable to existing structures
• single-point or multi-point architecture
• remote monitoring
• measurement history
• automatic drift detection
• configurable thresholds and alerts
• comparison of several zones
• possible temperature integration
• temporary or permanent solution
• scalable architecture

Strain gauges

Dimensions depend on the selected technology and model.

• Technology: resistive strain gauge / Wheatstone bridge
• Installation: bonding or mechanical fixing
• Number of points: configurable
• Orientation: suited to the direction of forces
• Cable length: configurable depending on the installation
• Protection: defined according to the project environment

Acquisition node

• Number of channels: configurable depending on the project
• Inputs: Wheatstone bridges / vibrating wire
• Temperature measurement: available depending on configuration
• Mounting: near the structure or in an enclosure
• Dimensions: depending on the selected configuration

• single-sensor or multi-sensor configuration
• configurable number of channels
• various cable lengths
• junction box
• local data storage
• mains power supply
• battery power supply
• solar power supply depending on the project
• PMI-CloudVIEW dashboard

Accessories

• adhesives and installation consumables
• surface preparation kits
• strain gauge protection
• mounting plates
• fasteners
• temperature probe
• mounting brackets