Project
The Strandboulevarden cloudburst tunnel
Cloudburst tunnels and other climate adaptations designed to future-proof urban and rural areas are complex civil engineering projects that require sophisticated engineering surveying services. The cloudburst tunnel beneath Strandboulevarden in Copenhagen is no exception. LE34 is on site.
The cloudburst tunnel beneath Strandboulevarden and Gammel Kalkbrænderi Vej in Copenhagen is being bored deep underground. The tunnel is two metres in diameter and approximately 1,100 metres long.
Control measurements and as-built documentation ensure quality
As part of Copenhagen’s cloudburst protection programme, HOFOR (Greater Copenhagen Utility) is constructing a cloudburst tunnel beneath Strandboulevarden. In future, the tunnel will help manage heavy rainfall and cloudbursts that currently cause streets and basements around Strandboulevarden to flood.
Documenting the alignment of the completed tunnel is essential to ensuring that it can handle the large volumes of water for which it is designed. The gradient of the tunnel tube is particularly important, as the water must be able to flow through the tunnel and into the harbour as quickly as planned.
LE34’s chartered land surveyors therefore carry out regular control measurements and prepare as-built documentation throughout this major tunnel project.
We work for Smet Group, the main contractor for the client, HOFOR.
Deep underground
We use a total station in the cloudburst tunnel beneath Strandboulevarden. This is high-precision surveying in which we make full use of the total station’s advanced EDM function.
Before: Setting out and as-built documentation ensure safe shafts
We are on site before, during and after the extensive underground work.
Before tunnelling can begin, four shafts are constructed to provide access for the crew and the extremely heavy tunnel boring machine. The shafts are not merely access routes: they also help ensure a safe working environment for everyone working in the excavation area. They are deep and narrow and must withstand demanding construction methods and extreme ground pressure on their walls, placing stringent requirements on the contractor’s construction.
As surveying consultants, we contribute by setting out and carrying out as-built surveys of the shafts’ secant pile walls, sheet pile walls and jet-grout columns. Our as-built documentation provides the data used to verify that the completed shafts meet the requirements before tunnelling begins.
During: Control measurements minimise risk
LE34 visits the site several times while tunnelling is under way to carry out control measurements and verify that the tunnel boring machine is moving precisely along the intended alignment.
Control measurements during construction give both the client and the tunnelling contractor, Smet Group, documentation of the actual conditions and allow any discrepancies to be corrected early in the process.
After: High-precision as-built documentation
The cloudburst tunnel is being bored in three stages. Once each section of the tunnel tube has been completed, we return underground with our equipment to prepare as-built documentation of the completed tunnel’s actual alignment and gradient.
Extensive experience of surveying in difficult-to-access locations
Over many decades, LE34 has built up extensive experience of complex control measurements and as-built documentation for major civil engineering projects, metro systems, tunnels, harbour piers and construction projects. Difficult-to-access locations – such as the bottom of a 12-metre-deep shaft or inside a tunnel tube – are no obstacle: our staff master both the technology and the precision required.
We use a total station in the cloudburst tunnel beneath Strandboulevarden. This is high-precision surveying in which we use the total station’s advanced EDM function (electronic distance measurement) and an angular accuracy better than 0.5 arcseconds to achieve measurements of the highest quality.
Contact us to find out moreRichard Lindquist Capion, Chartered Land Surveyor and Head of Department, LE34
Many different professional disciplines are involved in constructing the cloudburst tunnel, and the work of many people must be coordinated. LE34 therefore attends the tunnel at short notice whenever the next measurements are required, allowing the following phase of construction to begin as soon as our measurements and calculations are complete.
Find out more
Contact us
Richard Lindquist Capion
Chartered Land Surveyor and Head of Department
LE34 Copenhagen
Phone +45 7733 2172
rlc@le34.dk
