As Crossrail tunnel boring machines pass under parts of central London Getec will be monitoring building movements.
Using a novel multipoint hydrostatic levelling systems the tiny changes in level of buildings and services experienced as the ground relaxes can be recorded. In many locations Keller Geotechnique is carrying out compensation grouting and Getec will be monitoring the performance of this.
Pressure transducers are set with a starting pressure and any change in height creates a change in pressure. Measuring points are all connected to a header tank with a tube and thus the reference level. The other unique feature is the size of the units-as little as 10cm. These sensors can record level changes as little as 0.02mm. As both Leipzig and Cologne have already had cross city lines where these devices have been trialled we are pleased to be using them in London.
Walking around the West End you will see these devices on the corners of several buildings.