At this moment, it became serious and I had to look up all the techniques I want and don’t want. Below, you find the story-line in a logical order.
Structures (weldings) to the floor
In case structures (weldings) have to be made to the floor; this this first before putting in the ballast; Wasted work to drill or remove ballast to gain access to the floor again !
Below, a picture is shown of our ‘Lucie’ where the structures were welded before the concrete ballast was done.
Ballast
A ship without ballast is difficult to sail for the following reasons:
Maximum thrust can only be reached when the tunnel with the prop is completely under water. As soon there is air in the tunnel, this will negatively affect the thrust very much.
A inland ship is completely flat bottom and acts like a balloon on the water; sidewinds will easily blow away the ship and currents will easily the ship.
An empty ship raises high from the water and may not be able to pass a low bridge
A full loaded ship might be too deep to pass an undeep river/canal.
Openings like windows or water drains need to be minimum 30cm above the water line; for the German Rhein 50 cm above the water line.
A cargo ship can change it load, but a houseboat has a fixed load where a perfect balance needs to be found. Also take into account that dry docks might have limitations in weight and depth in the water. Zelzate dry-dock seems not to be comfortable if the head of the ship is more than 0.70m deep in the water.
Please notice that an empty ship will naturally have the rear deeper in the water because of the weight of the shippers house, the engine and the (diesel)tanks. to have the ship equally deep, it might be considered to ballast more the front than the rear.
A spits has a ratio of about 10:1 (length versus width), so it can easily ‘roll’ if the ballast is too much left or right. For this reason:
put a heavy point of ballast (e.g. 5000l water tank) in the middle axis line of the ship
make an equal left / right double point of ballast (e.g. one 2500l water tank left and 2500l water tank right).
When adding ballast, do not use water-level tools with reference on the ballast; they might confuse you when the ship rolls and infinitely asking for more ballast.
When considering liquid ballast (like concrete), be careful that it cannot unintended flow to the deepest point of the ship and makes the ship inclination worse or even rolls over the ship!
No ballast:
Your ship will raise from the water and look big. This is an option for a ship to sail anymore on own power anymore. The Ship can still be pushed/towed by another ship.
Permanent ballast:
You can ballast with anything what has weight.
Specific weights:
Concrete: 2.5 ton / m² Iron: 7.6 ton / m²
We ballast our ship with 18cm of concrete, which was more than enough because of the unplanned extra 10cm of flooring screed.
Temporary ballast:
This is ballast which you can remove again.
Water tanks can easily be filled or emptied.
Ballast on deck can be added or removed.
Ballast below deck might be an elaborate and heavy job to add/remove.
When a spitz ship has a surface of 40m x 5m = 200m²,
2 ton ballast will press the ship 1 cm in the water.
20 ton ballast will press the ship 10 cm in the water
200 ton ballast will press the ship 100 cm in the water
350 ton ballast will press the ship 175 cm in the water; this is about typical maximum cargo of a Spitz
Please take into account that after this first step of intentional ballast, there will still be more temporary or unintended ballast. Some examples are:
Empty versus full diesel-tank
Empty versus full water-tank
Building materials like, screed, wood, plaster
Interior materials like furniture, radiators
Below, you find picture how we have ballast our ship ‘Lucie’ with 45 tons of concrete, Saturday 1th of March 2014;
The total cargo space was 30m x 5.08;
We left open 5m at the engine to gain height for the drink water tanks, which will also mean ballast on themselves;
We left open 1.4m at the front to gain height for the rain water tanks which will also mean ballast on themselves;
We left open 19 cm left and 19 cm right to let pass the big pipes for water and ventilation.
We made a construction in Douglass wood of 18 cm height which took about 2 days. This wood was to avoid that the liquid ballast would flow to the lowest point (rear of the ship). Once the concrete was dry, all wood is removed so that concrete tiles of 1.5m² remain that can use the former wood space when the ship grows or shrinks under temperature. The wood was then cleaned and reused for the living room ceiling constructions. See later.
23.6m x 4.7m x 0.18m x 2.5 ton / m³ = 45 tons or two trucks full and a concrete pumping machine. Took about half a day.
It was very accuratly correct amount of concrete. In fact, we had just a bit too short for the last square. The good guy from the concrete pump had the magnificent idea to loosen the residue in his pump which was just the amount we needed. So the estimate had an accuracy of 10 kg on 45 000 kg; proud of it :-).
Now, happy everything went well, had a cup of coffee in the cabin and let the concrete dry for a few days.
