Structural monitoring in London

London as a location is one of the most popular destinations in the world. The number of people visiting or working in England's capital city is vast and the existing communication networks have long been identified as requiring a major overhaul to keep up with the through-put of people.

Two sep arate projects have been implemented to aid in relieving the pressure on the system, Thameslink 2000 and Crossrail.

Project idea started in 1948

Thameslink 2000 was originally proposed in 1991 to upgrade transport-links between the north and south of London, whilst the approved Crossrail project in 2007 has a longer history and was first discussed as a project already in 1948.

The final Crossrail project proposals include ambitious plans to create a new railway line running from Maidenhead, 50 km to the west of central London, taking in a connection at Heathrow Airport, diverging at Whitchapel and terminating at two eastern destinations, the main line at Shenfield, 50 km to the east, whilst a spur ends at Abbey Wood south of the River Thames.

Complex tunnelling

This of course means that there is a requirement for extensive tunnelling to take place beneath the city itself. In fact, much of the route from Paddington through to just east of Whitchapel / Canary Wharf is to be underground, with around 42 km of new tunnels beneath central London. This task is made more difficult thanks to both London's geology and the complex array of tunnels that already exist beneath London! In addition, there will be eight new subterranean stations constructed along the tunnel's route which will also offer links into London's famous Underground network.

Largest precision robotic order ever

For the project to be successful, and to maintain total integrity of London's landscape, extensive monitoring of the works would obviously be required. Morgan Sindall, part of the BBMV partnership (including Balfour Beatty, ALPINE BeMo Tunnelling and Vinci Construction) tasked with the C510 contract construction works, selected

105 Topcon MS05AX high precision robotic total stations to fulfil the task. This order, placed through UK distributor ESS Safeforce is thought to be the largest ever order of ½ second instruments from any manufacturer.

Matrix Detection

Alastair Cruickshank - Engineering Survey Manager at Morgan Sindall commented, "We are very impressed with the Topcon MS05AX Total Stations supplied to us through ESS. The build quality and performance is extremely impressive. The instruments always lock on to the correct prism to be measured, even in challenging environments such as tunnels where there may be several prisms in the field of view of the instrument. The Matrix Detection function to automatically find and measure

prisms has also saved us a lot of time. We are positive that we made the right choice in choosing this innovative instrument from Topcon." Matrix Detection is Topcon's latest technological feature designed to save time and increase efficiency whilst setting up complex arrays of prisms for monitoring systems. Using intelligent algorithms and high accuracy imaging sensors, the MS05AX is able to detect and locate all established prisms, even in low light or dark conditions! Once located, the MS05AX then measures the prisms quickly and reliably, virtually eliminating any sources of human error.

Crossrail 2018 completed

Work on the project commenced in May 2009 and it is expected that the first trains will be running on the completed system by 2018, and should soon be up to full peak time capacity of 24 trains per hour, allowing many journey times across London to be cut dramatically.