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1. Index
2. CMCS at BRE
3. Development of AMS
4. Non-destructive testing of Marine Jetties
5. Fixed sensor monitoring of Diaphragm walls
6. Monitoring Buildings during Redevelopment
7. Tunnel Monitoring
8. Embankment Systems
9. Loggers
10. Tunnel Distortion Monitoring
11. In-place tilt monitoring system
12. Tunnels Interaction System
13. Re-Development of Small Properties
14. Viaducts
15. DLR at Mansion House
16. Tunnel Monitoring System (Discrete beams)
17. CTRL 240
18. Dams
19. Electro-levels
20. Movement indicators
21. Results of Charing Cross Load Cells
22. Non-destructive testing of concrete structures
23. Radio in Construction Monitoring
24. Settlement Reducing Piles
25. Land Surveying and Total Station Monitoring
26. Vibration Monitoring
27. Monitoring the complete strain history of concrete elements
28. Past CMCS Projects

The control of many construction processes comes down to whether work activities are causing movement to existing infrastructure. Waiting until movement can be observed by the engineer in charge is usually too late to prevent damage and there is a need to observe small changes before they become significant. The CMCS tilt indicator is designed to provide personnel carrying out work activities immediate warning of movement occurring. For simplicity and ease of installation the device does not store data, nor can it be connected into a computer-controlled system; for more sophisticated movement warning systems see CMCS brochure.

The photograph opposite shows the movement beams being used in 1998 to monitor changes in cant of the track during grouting operations to seal the Mersey Loop tunnels against water ingress. The beams were carried to their required location by the engineer in charge and simply placed either across the track to monitor change in cant or along the track to observe uplift. As grouting proceeded, relative movements of 2 mm on the beam caused the warning light to flash. Grouting was immediately stopped and as the pressure reduced, so the differential movements reduced to an acceptable level.

The two photographs below show the latest version of the movement indicator beams being used while one of the tracks in a main line railway tunnel was removed, including all ballast, and replaced by a new high speed track bedded on solid concrete. The beams are highlighted by the white arrows in the photographs.