New dredging sensors at work in Port of Esbjerg

Author: Karina Lumholt

Esbjerg Port, once the principal fishing harbour of Denmark, has today become the Danish capital of oil and gas and Europe’s leading port for shipping of off-shore wind turbines to the North Sea.

Esbjerg Community is currently extending the harbour with a new urban area and marina with the objective of giving the citizens better access to Esbjerg’s attractive marine and beach area. The new urban space will create close contact between the city centre and the harbour area and establish a centre for maritime leisure activities as well as new commercial and residential areas. 

The plan is to create a new harbour lagoon with marina, new beach area, and eventually plan for a hotel and an art museum on the new peninsular.

Machine control visualises the excavator’s work under water

VG Entreprenør A/S, a construction company with expertise in all types of coastal area projects, started working on the project this summer and is planned to terminate by the end of 2018. The company has specialised in coastal protection as well as harbour and port installations. In Esbjerg harbour, their primary job is excavating and stone work on dikes and piers. Claus Agger Sørensen works as the daily manager on the project. Claus prepares the drawings, orders stones, calculates the volumes, allocates resources and manages the overall logistics.

“Right now, we have four excavators working on the site and all of them are equipped with machine control from Leica Geosystems,” Claus explains. “We used to use floats, buoys and stakes for measuring and controlling of the excavation under water. With machine control, it has become much easier when the actual digging under water is being visualised on the in-cabin panel.”

Construction of stone piers starts with the drawing of its layers. Claus draws the profiles in AutoCad. The layers are made up by a core of sand or stones, a layer of smaller filter stones, a filtration fabric and a layer of larger stones on the top. Each layer has a profile file that is read into the iCON office software where they are converted into 3D models, terrain files and line files and then read into the machine control solutions on the machines. This is done through the web-based service Leica ConX.

“The Leica ConX tool makes it possible for me to on several projects at the same time,” says Claus. “I can help with a project that takes place in another part of the country at the same time as I am working here in Esbjerg.”

Claus is also using the automatic logging of the work to create as-built documentation.

MSS420 dredging sensors

The construction of stone piers is a market niche for VG Entreprenør. It requires specialised machine operators who have the skills and experience to build all the layers and use the excavator to weave them together as a jigsaw puzzle.

For a couple of months, VG Entreprenør has worked with the new Leica MSS420 dredging sensors and has benefitted from the advantages of the new underwater application. The new dredging sensors have pressure tight connectors, robust stainless-steel sensor brackets and rugged cabling. This special design ensures a much longer lifetime of the sensors.

“We are working in a very rough environment with stones, wind and weather. Especially salt water is very hard on the equipment. We are also working on a very tight schedule on this project, and we simply cannot afford long downtime on machines. The Leica MSS420 sensor helps us keep the machines up and running for the planned operations,” Claus continues.

Marcus Grevelshoej, product specialist for excavator and wheel loader solutions, foresees that the new Leica MSS420 dredging sensors will prove to be very useful in many construction projects such as deepening of harbours, digging of cables underwater, harbour installation, coastal protection, denaturisation and digging in raw material lakes.

“The MSS420 sensor can be programmed to boom 1, boom 2, stick, bucket and even tilt sensor. This makes the changing of sensors very easy, even for less experienced operators on the construction site,” says Marcus.

All excavators equipped with iCON excavate and GNSS can easily be updated to use the new submersible sensors.