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Close your eyes and think about the main material of a boat. Very possibly wood be first that comes to mind, and it’s normal: we have been sailing in wooden boats for millennia, and we continue to do so. But it is also logical that the steel that dominated the 19th and 20th century shipsand the current sea monstersideas haunt you. And most likely you have not thought about another material: the concrete. But yes, for 150 years we were creating concrete boats, and far from being crazy, it was the most logical idea. And they were even used in the First and Second World War. a french. One fine day in the mid-19th century, a French gentleman named Joseph-Louis Lambot It occurred to him to build a boat. Not just any one: a reinforced concrete one. There was one problem: in 1848, they had no idea what reinforced concrete was. This material, basically, is the mixture between concrete and steel. Both combine to create something with much greater structural resistance and have been the basis of the most imposing skyscrapers, dams and almost any construction of the last century since its invention. Well, it was Joseph-Louis who came up with the idea of ​​combining the two materials. At least, it attributes the invention of reinforced concrete to this man. As always, there is controversy over the dates, who patented reinforced concrete, who built the first slab, etc. But anyway: Lambot wanted to test his invention and built a small boat of less than four meters with the aim of exhibiting it at the Universal Exhibition in Paris in 1855. Quite a few advantages. Basically, the interior was wire mesh covered by cement and Lambot’s idea was to completely replace wood. The invention was liked, but it did not really attract the attention of boat manufacturers. Some barges were created for European canals, but little else. Everything changed when the Italian engineer Carlo Gabellini built the Liguria in 1896. It is what we consider to be the first reinforced concrete ship designed to sail on the high seas. And, really, it made sense to create reinforced concrete ships. It is a material that has great resistance to corrosion, so the marine environment does not damage the hull, reducing maintenance (which also has it) and extending its useful life. It offered good thermal insulation, so perishable resources could be transported in better conditions and there were no fire problems. The Namsenfjord In the absence of bread… A few years later, the construction of these concrete ships expanded and other countries began to build them, especially cargo ships. But of course, we are in 1914 and that means that something happened: the World War I. And beyond the advantages of concrete over other materials, the world was forced to create concrete boats for a very simple reason: there was no steel. The militarization and industrialization of the belligerent forces caused a situation of steel shortage. The ships were important, since the naval supremacy It has always been a determining factor in a conflict, but with the steel necessary for a destroyer many other things could be created. And the problem is that they had to continue building ships because there were resources to move worldwide. The First World War. The revolution came with Namsenfjorda Norwegian ship that, in 1917, demonstrated that self-propelled concrete boats could be made. It was 26 meters long and weighed a whopping 400 tons and most importantly: the United States saw that there was potential in these ships beyond serving as freighters powered by an auxiliary ship. Thus, they created the Emergency Fleet Corporation program with the objective of producing 24 concrete vessels. It was a failure: those that were completed were done after the war, so they had to be used for other things. One was the SS Faithwhich was going to serve in the war, but in the end it was left to be used in transportation work in the United States. It was launched in 1919, was in service until 1921 when it was sold to Cuba and had a length of 97.54 meters. A year after Faith, the SS Selmaan enormous mass of reinforced concrete measuring 129.54 meters in length that was launched just the day Germany signed the Treaty of Versaillesending the First World War. It ended up being used as an oil tanker in the Gulf of Mexico. With sails and a secondary support engine Devastating disadvantages. With the war over, interest in concrete shipbuilding waned. It still had advantages, since building them was much cheaper than making them in steel or iron, but if we mentioned a series of advantages before, it is important to now know the disadvantages (which outweigh them, and by far). To match the strength of a steel hull, a concrete hull is thicker, which has several limitations. On the one hand, it weighs more, so it also has a greater draft, the ship’s movement is slower and more fuel is needed. Being thicker means that there is less interior space for cargo, since the useful volume is reduced. This weight means that the engines must be more powerful and the fuel tanks must also be larger, so the investment in this part is greater. The dam to build it must also be monstrous because parts cannot be welded, as in a steel one, and then there is the impact resistance. Second World War. Metal breaks, yes, but it has greater elasticity than concrete. This material, however, is much more fragile when faced with impacts. A collision causes a crack in the hull, and this in a boat that weighs so much is a condemnation. That is why, after the Great War, the concrete ship project was abandoned, leaving its construction practically limited to cargo barges, but then the Second World War arrived, and the steel needs of the previous one were repeated. However, the US program was not as ambitious as the one they started … Read more