This extensive redevelopment project

MONITORING OBJECTIVE

During the extensive redevelopment works of Pilgrims Quarter, Newcastle, several structures require observation and monitoring to ensure they were not experiencing excessive movement due to the works. These structures included an active underground metro line running directly beneath Pilgrims Quarter.

INSTALLATION CONSIDERATION

SENSORS: The internal walls of the tunnel and shaft are of steel construction and sensors required a non-destructive installation.

TOTAL STATION: The addition of a total station to the monitoring array is required to measure specific positions within the tunnel to identify any movement. The total station and M1 comms box require a stable and reliable power supply.

POWER: The sites power is provided by a 110v mains power feed. The reliability of the power supply is unknown.

MONITORING SYSTEM

1no. Trimble S7 1"

1no. M1 Settop Box

9no. Tiltmeters

4no. Accelerometers

2no. Vibrometers

94no. Monitoring Prisms

1no. LoRa Gateway

OUR COMPONENTS

1no. Dyna-mo Vision with 2 cameras

1no. 200Ah 110vdc Back-Up Power System (Custom)

15no. Magnetic Mount Kits

1no. IP Power Monitoring Camera

The tiltmeters, total station and prisms are installed metro tunnel and shaft. Accelerometers and vibrometers were installed as an additional level of monitoring to observe the vibration experienced by the structures during the works. The Vision system is installed to monitor activity in the Metro tunnel identifying if sensor readings are relating to rail activity, other activity in the tunnel or if sensor triggers are relating to the ground level construction works.

PROJECT NOTES

The monitoring system installation was completed over several nights with the tiltmeters, accelerometers and vibrometers installed, utilising magnet mount kits, were in place with no need for drilling or fixing.

The monitoring installation will be in situ for approximately 12 months in total with the sensors being repositioned on to the proposed piled steel retaining wall once completed.

CONCLUSION

Utilising our magnetic mount kits enabled the sensors to be quickly and easily relocated to the new retaining wall without the onerous task of undoing the fixings from the old wall and re-drilling and fixing to the new wall.

As a coincidental benefit, the sensors were regularly knocked and hit by site workers and the compacting machinery as the channel they were operating in was less than 1m. Had the sensors been drilled in to the old retaining wall, the sensors would likely have been damaged. As they were magnet mounted the sensors were simply knocked off when hit hard and were able to be repositioned undamaged.

SUPPORT

We attended the site to support the installation and revisited some weeks later to resolve an issue with the back-up power system. The vibrations from the compacting works hard worked loose a wiring connection within a sealed unit which led to the battery inconsistently recharging. The system was completely checked and all connections tested to, as far as possible, prevent a repeat occurance.