Colindale Station Redevelopment, North London UK

Client
> Morgan Sindall

Sector/Market
> Infrastructure

Services
> Monitoring – Structural Health

Location
> Colindale Station, North London, UK

Project summary

The Colindale Station, located on the Edgware branch of the Northern line in the London Borough of Barnet, is currently under redevelopment works.

The current station layout comprises of a surface entrance and a ticket hall to the western side of the station. The platform is situated in a cutting 4.0m deep, retained by masonry gravity retaining walls, which were constructed in the 1920’s when the Northern line was constructed. Access to the platform is provided by a footbridge connecting the ticket hall to platform via stairways, one facing north and one facing south.

The station car park is located to the east of the station. The plot immediately to the west and north of the current station ticket hall is vacant.

The brief

Murphy Geospatial have been instructed by Morgan Sindall to carry out structural health monitoring of all surrounding locations marked at The Colindale Station Redevelopment Project during the demolition and construction of Colindale London Underground station.

The challenges

During piling works near the tracks, these had to be covered for protection, which also concealed the instrumentation requiring surveying. As a result, Murphy Geospatial had only a short window of access and needed to coordinate closely with the site team to complete all necessary work within the available shift.

Our work

A total of 152 tilt sensors were installed on the project: 12 x Wall734 and Wall735 (6no. on each wall), 120 x on Northbound and Southbound tracks (60no. tilt sensors on each track) and 20no. on the Platform (10no. on each side of the platform – SB and NB). These nodes work off a wireless FlatMesh system, connecting to a nearby gateway and solar panel to provide constant data to an online portal.

208 monitoring targets were installed on the Northbound and Southbound tracks, platform, retaining walls, overbridge and cable rack along with 19 control targets away from the bridge outside of the zone of influence and 19 existing or newly installed ground control points.

A CCTV system was installed to record activities on the east cess and island platform. This 24/7 plug-and-play video monitoring solution incorporates video analytics and motion-triggered recording. The system is designed to enhance structural health monitoring installations by providing video data for comparison with sensor data, enabling remote validation of events and sensor readings.

54 crack tell-tales have also been installed on the existing cracks of the Wall734 and Wall 735.

Our team

Our monitoring team consisted of a project engineer to prepare and supervise the installation works, a monitoring engineer to install the system and setup the network, and a survey team to carry out the installation and survey of the control network. A designated project manager was assigned to oversee the automated monitoring system so that this ran smoothly and that the client and TFL were regularly informed on the monitoring results.

Results

All systems were installed and running within the allocated shifts required to get everything setup. The system remains in place for the duration of Morgan Sindall works.

The observation data was viewed via an online portal and summarised in a daily/monthly report. If a trigger was breached or a critical event occurred, the client and TFL were ready to take the necessary action before it was too late.

The success of this project underlines our reputation in delivering services to equip our clients with the data and information they need to make informed decisions at every stage. We draw on the experience and skills of our people to deliver geospatial certainty our clients can trust.

Contact

For more information on this project, please email info@murphygs.com or call us on +44 (0)192 362 4800