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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

To reduce the settlement and bending stresses in the heavily reinforced raft supporting the QEII Conference Centre Westminster a limited number of piles were installed. The foundations were constructed by John Mowlem Ltd. The load cell used to monitor the load in the pile at the raft interface as well as raft presure cells were designed and installed by G Price and I F Wardle, while at the Building Research Establishment. The photograph opposite shows the top down construction of the basement at the founding level.

The photographs above show the various stages of construction of the load cell. The left photo shows the preparation of the pile for the load cell. The middle photo shows the completed load cell fitted with its 3 mm soft membrane and reinforcing bars with pressure pads to link with the raft. The right photo shows the first layers of the raft reinforcement installed around the cell.

The above plot shows the load carried by the pile. The reduction in load in 1981 was due to the foundation contractor removing his plant from the site. The rapid increase in load was due to the main building works, followed by the less steep fitting out stage. Since January 87 there has been a slow reduction in load, thought to be due to a rise in the water level in the area. The general fall in load was also recorded by 4 raft pressure cells. The load cell and the raft pressure cells only monitor effective pressure, i.e. water pressure can pass either side of the soft membrane.