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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

A more immediate use of the additional automatic monitoring sense is the control of transport systems. The diagram below represents a typical interaction problem faced by London Underground Ltd, i.e. of new tunnelling works passing close to their existing running tunnels. To monitor movements of the running tunnels CMCS installed ten 3 m electro-level beams in each tunnel.

	The rate of interaction between a new well-formed and supported tunnel in the ground and existing tunnels can be represented on a Log scale.
	The elastic movements taking place relatively quickly, say over a period represented by 1, the rate significantly slows over the next 10 periods, and slows still further over the next 100, with the total movement taking approximately 1000 periods.

For well-constructed tunnels the base period is approximately one day. The above plots show the movement after 10 hours. By 10:00 hrs on the 17th both running tunnels had deflected about 5 mm. The monitoring system (simply) installed to observe interaction of a one-off event as an optimum life of approximately 100 days. The small movements that take place over the 1000 day period would be best observed by combining an automatic system with manual checks, such as precise levelling. The interpretation of the long- term data requires a detailed log to be kept of all site activities that may affect the left-in-place monitoring system.