Survey

Sjótækni ehf. has now established a department within the company, which specializes in ocean and water research. The department will concentrate on bottom and depth measurements of all kinds, seabed sampling, sediment thickness measurements and core drilling. Also surveying and mapping. With the purchase of the latest equipments in that field, it is now possible to measure and make a 3D map of places that have not been accessible before.

 

Multibeam measurements

To meet the modern demands of accuracy, speed, safety and potential, we at Sjótækni ehf, decided to go undisturbed paths with a gear pickup for the survey. We invested in a remote-controlled boat, programmed with a pre-determined navigational route, or controlled by land or other boat, via on-board cameras.

By going this unconventional way to measure the bottom, you can offer a much quicker response, and you can go to places that have not been measured before. It is also possible to measure where it is not considered advisable because of the risk of sending manned crews. This includes the intake of power plants, the sewer scrub and where the currents and suction create dangers. Ship traffic and narrow areas are no longer a barrier to this type of boat.

 

 

 

 

Technical information:

The boat is 200 cm long, 105 cm wide and 85 cm tall. It weighs about 95 kg.

It is electrically powered, which means that no carbon footprint results from its use. The battery charge lasts for 10 hours. Because the boat can be found in a regular van or trailer, it is quick and easy to transport anywhere. Two men can carry it between them and launch it almost anywhere. It can also be launched with a landing crane.

 

 

 

 

 

Some more innovations:

As visualized in this illustration, there are two measuring devices aboard the boat. The blue beams represent the multi-beam and the area over which it extends to the sea bottom. But the red beams represent a laser scanner, which can measure the area above the water surface. This technology provides a comprehensive three-dimensional image of the seabed and the landscape around. This means that there is no need anymore, to send a land surveyor to measure the landscape. This is especially useful when calculating the amount of material in floodgates, landfills and similar areas. Also the position on the seabed is much better, for example while searching for pipes, cables or lost parts under the surface of lakes or sea.

 

 

 

 

Further options:

To enlarge our service to customers and to get the most of our tool, it is possible to remove the laser scanner from the boat and use it separately and in multiple ways. For example: you can place the scanner on an automobile, tripod or even a kite to perform 3D-measurements of a landscape. This gives us incredible possibilities for accurate 3D-surveys of harbor structures, houses, roads, line routes and numerous other things that need to be promptly and accurately recorded.

Here you can see a Lidar scanner of the same type under a drone, that is carrying out an inspection of high voltage lines.

 

Bridges and other road construction

In addition to landfill and perimeter surveys, it is now easier to display bridge pits and foundations of all kinds, due to the small size of the boat. It can easily be navigated around the bridge pier foundations, to perform inspections of their strength and durability. Moreover, the entire position of the bridge structure becomes more apparent through the Laser scanner. See photo

As mentioned above, a combination of this top to bottom technology is ideal for measuring landfills, pre-, intermediate- and post-surveying, leveling and volume calculating materials and estimating the progress of the overall volume of a project.

 

 

Being able to measure at the same time, both above and below sea level, saves a lot of time and makes all measurements much more accurate than previously known, since the land survey is now very densely spaced, but not individual dots after a particular meter.

The lower part of the courtyard, measured with a multiregiograph, but its upper part and the lighthouse is measured by a Lidar scanner

 

Thickness measurements:  

Sjótækni offers its customers the possibility to measure the thickness of seaweed or Seismic seabed. Such measurements are necessary to find out about the amount of material that lead to the volume calculations. Those who are taking material from the ocean floor need to be able to find out how thick and large sediment layers are in total. It also needs to be possible to see where they exactly are. This is all possible, with our thickness measurements. Additionally, it is easy to see what is far down on a bedrock, or hard bottom when clients are planning bridges, or other structures, such as road construction or deciding about a surface layer.

 

 

 

 

 

Core drilling:  

Core drilling is often carried out together with a sediment thickness measurement, to confirm which material is in each sediment below the surface. Mostly it is difficult to measure the particle size or material type of each sediment with a set thickness measurement. Core tracing on the other hand, confirms the content of each sediment layer. This way it is possible - with great precision - to see what type of material is in each sediment layer, and thereby find the right particle size or type of material being sought. It is also easier to estimate the bearing capacity of the substrate for construction work.

 

 

 

 

 

 

 

Gripclaw:

If samples of the seabed are to be taken, we have at our disposal so-called claws, which can be lowered to the bottom. It is pre-tensioned before being dropped and closes automatically when it hits the bottom. Thus, it seizes all the material or vegetation beneath it. It is basically a closed shovel, that holds the sample inside on the way up to the surface - particularly suitable for research. No divers needed. A camera, that shows both - the clones and the bottom at the same time, can be attached to the claw, to making it easier to only retrieve what is needed. An inexpensive and well-working solution.