Case Study

Transportation | Roads & Railways

Finch West Light Rail Transit – Line 6 Construction

Problem

The project team was tasked with the installation and monitoring of 1,200+ monitoring points across the length of an 11-km light rail transit alignment, and the 18 associated stations. The project transits a well-developed urban setting and is scheduled to be phased over a 4-year project period, starting in late 2019. Instrumentation is varied and includes surface-mounted monitoring systems on active roadways and structures and below-grade systems in active subway tunnels. The challenges of monitoring on the project are complicated by limited access to installation points, changing site conditions, an evolving instrumentation plan, and a large and diverse user base requiring access to an extensive sensor database estimated to manage millions of data points and measurements over the construction phase of monitoring. Additionally, the solution requirements included pairing various sensor technologies with a single monitoring platform while striking a balance of financial stewardship backed by reliability.

 

Solution

To meet the many challenges of the Finch West LRT project, GKM worked with sensemetrics to develop a dynamic monitoring solution that consists of a cost effective and easy-to-deploy wireless system comprised of Loadsensing wireless nodes to automate a wide range of vibrating-wire geotechnical sensors, as well as sensemetrics Thread devices to automate more complex sensors such as Measurand ShapeArrays and Leica Automated Motorized Total Stations (AMTS). Both automation devices stream sensor data to sensemetrics’ platform for real-time access to sensor measurements on an evolving reading frequency to meet project requirements. Areas that require less frequent reading intervals are captured manually using various data collection methods (water level sounder/readout, manual inclinometer probe, or manual survey targets) and are also uploaded into sensemetrics’ platform. Lastly, the selection of sensemetrics was based on the flexibility and scalability to meet the dynamic project requirements commonly associated with large LRT projects.

This included support for the following sensor technologies:

Automated Vibrating Wire Technology

Multi-Point Borehole Extensometers (MPBX)

Piezometers

Strain Gauges

Pressure Cells

Automated MEMS Technology

Electrical Biaxial Tiltmeters

Electrolevels & Tilt Beams

In-Place Inclinometers

Track Monitoring System

Manual Measurements

Survey Prisms

Manual Levelling Points

Inclinometers

Standpipe Water Levels

Automated GeoSpatial Measurements

Automated Motorized Total Station (AMTS)

Additional productivity enhancing tools that were implemented include sensemetrics’ Reporting and Documents modules. Reporting auto-generates and delivers formatted PDF reports to key stakeholders on a customizable schedule or in response to threshold exceedances. Documents provides a secure and cloud accessible document share that uniquely associates photo documentation, reports, and other documents with project assets – providing a comprehensive shared resource for unification of project instrumentation records.

Project Details

Location: Toronto, Canada

Date: 2019-2025

Owner: Metrolinx | operated by Toronto Transit Commission

Engineering: Mosaic Transit Group

Instrumentation: AIM, GKM Consultants

Project Type: Subsidence Monitoring, Railway Deformation, Structural Stability