Designing a new CONCRETE BOAT

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  • heavyweather
    Senior Member
    • Apr 2012
    • 463

    #46
    Re: Designing a new CONCRETE BOAT

    It's short. Not really wide. Looks high.
    Have you calculated the vertical weight distribution?
    Done a light prototype of the hull?
    350cmX89cm with much weight high up sounds just a little tippy.
    I figured that displacement would be enough but that doesn't help when it rolls the moment it starts floating.

    What calculations and trials have you done before?

    Comment

    • FishoutaFlorida
      Senior Member
      • Jan 2017
      • 858

      #47
      Re: Designing a new CONCRETE BOAT

      Originally posted by johnw
      Absolutely! Concrete canoe is an extra-curricular portion of a civil engineering education. Not a place for analysis paralysis, but one for getting the job done. And it looks like german... and his crew did just that!

      Not sure this is the right spot for detailed discussion, but since it is a part of my past I've got to chip in.

      We always took two to competition. Whatever we had concocted that year and a Destroyer from years past. New paint and was good as new.

      Strategy was to race hard with the new one...varied success. Then challenged all to a demolition derby afterward and brought out the Destroyer. Also the newest rig so we wouldn't seem aloof.

      We left a lot of concrete on the bottom of the lake, but the destroyer still lives! (I think).

      But no matter what, a great experience! We came back with an understanding of deadlines and reality, budget and finding sponsors. And for german... to take the initiative to engage boat builders and share his experience with us, Kudos!!! Keep it up!
      Last edited by FishoutaFlorida; 10-01-2017, 08:08 PM. Reason: needed to punch up finale
      “Perpetual optimism is a force to live by.”

      Colin Powell

      Comment

      • germanhiguerav
        Junior Member
        • Aug 2017
        • 20

        #48
        Re: Designing a new CONCRETE BOAT

        THANK YOU SO MUCH FOR SUCH ENCOURAGING COMMENT! its really what i needed i was already scared my stuff will sink but according to the math this boat wont sink however it may spin like crazy i dont know !
        Originally posted by FishoutaFlorida
        Absolutely! Concrete canoe is an extra-curricular portion of a civil engineering education. Not a place for analysis paralysis, but one for getting the job done. And it looks like german... and his crew did just that!

        Not sure this is the right spot for detailed discussion, but since it is a part of my past I've got to chip in.

        We always took two to competition. Whatever we had concocted that year and a Destroyer from years past. New paint and was good as new.

        Strategy was to race hard with the new one...varied success. Then challenged all to a demolition derby afterward and brought out the Destroyer. Also the newest rig so we wouldn't seem aloof.

        We left a lot of concrete on the bottom of the lake, but the destroyer still lives! (I think).

        But no matter what, a great experience! We came back with an understanding of deadlines and reality, budget and finding sponsors. And for german... to take the initiative to engage boat builders and share his experience with us, Kudos!!! Keep it up!

        Comment

        • germanhiguerav
          Junior Member
          • Aug 2017
          • 20

          #49
          Re: Designing a new CONCRETE BOAT

          no prototypes or anything like that , by the way i just saw a brazilian team with a 500kg canoe floating and that thing was smaller than mine and it looked super heavy and mine doesnt even look half that heavy so i dont even think my canoe is even +300 kg and the shape is well defined today i will upload more photos of it!
          Originally posted by heavyweather
          It's short. Not really wide. Looks high.
          Have you calculated the vertical weight distribution?
          Done a light prototype of the hull?
          350cmX89cm with much weight high up sounds just a little tippy.
          I figured that displacement would be enough but that doesn't help when it rolls the moment it starts floating.

          What calculations and trials have you done before?

          Comment

          • johnw
            Senior Member
            • Nov 2001
            • 28589

            #50
            Re: Designing a new CONCRETE BOAT

            Well, it looks like a bomb in those pictures, but that's mainly down to the color. Perhaps you could name it UXB, to intimidate the competition.
            On the trailing edge of technology.

            https://www.amazon.com/Outlaw-John-L.../dp/B07LC6Y934

            http://www.scribd.com/johnmwatkins/documents

            http://booksellersvsbestsellers.blogspot.com/

            Comment

            • MN Dave
              Banned
              • Jul 2011
              • 3120

              #51
              Re: Designing a new CONCRETE BOAT

              Originally posted by germanhiguerav
              by the way it wont sink theoretically because buoyancy is 650kg +
              and im in the 300-400 kg range
              It will float in calm water with a 200 kg load and 2cm of freeboard. As long as the load is very careful not to rock the boat and there is no wind and no waves, it may stay afloat. I have two canoes, a 3.25m long, 71cm wide cedar lapstreak and a 3.5m x 71cm tortured plywood that weigh less than 15kg. With my 90kg mass, they ship water over the bow in a 15cm chop if I head at any angle to the waves. someone under 70kg has no problem. Another similar canoe that is 3.8m long does not ship water under similar conditions.

              Do the rules allow the use of surface bonding cement? It might save a lot of weight. It contains alkali resistant glass fibers and seems to have reasonable tensile strength, but I can't find that information. It is probably too late to look at Spider Lath, but if I had the time, I would hit them up for a free sample. I have spent at least 15 minutes researching this, so my advice may not be as good as your experience.

              I read about a company in Maine [probably in National Fisherman in the late '70s] that intended to build ferrocement boats commercially. They started with a study to determine the optimum ratio of cement to steel. In every category, strength, cost, whatever, the optimum ratio was 100% steel, 0% cement. They decided to build steel boats...

              EDIT There is something called ultra high performance concrete. I found one source, Ductal
              For more than 25 years, we’ve been producing the most advanced range of Ultra High Performance Concrete technologies and services. Born from the desire to minimize inputs while maximizing performance, Ductal® stands for optimal strength, ductility and durability. Decades of global practice, research and development have allowed us to acquire the technology and expertise needed to bring the most ambitious projects to life —without a hitch, anywhere in the world. Our team consists of a diverse collective of licensed engineers, architects, construction consultants and field technicians — all working directly with our clients to develop tailored but pragmatic answers to some of the most important questions in the construction industry today. By inventing construction materials that use less and last longer, we’re enabling more responsible built environments that lift up communities while being more respectful to their natural environment. For the sake of people and the planet we all depend on, we’re bringing concrete solutions to tomorrow’s challenges.
              Last edited by MN Dave; 10-04-2017, 11:38 AM.

              Comment

              • germanhiguerav
                Junior Member
                • Aug 2017
                • 20

                #52
                Re: Designing a new CONCRETE BOAT

                heres the new picture we just need to make a little reinforcement of concrete in the inside a thin layer only and thats it folks! i will record a video later and upload it !IMG_1987.jpg

                Comment

                • koederfischgriller
                  Senior Member
                  • Aug 2014
                  • 152

                  #53
                  Re: Designing a new CONCRETE BOAT

                  Wow, very nice! Is that a Mini Clubman behind this Trough?

                  Comment

                  • germanhiguerav
                    Junior Member
                    • Aug 2017
                    • 20

                    #54
                    Re: Designing a new CONCRETE BOAT

                    IMG_2081.jpgIMG_2102.jpgIMG_2083.jpg
                    Guys heres the new update of the canoe today i will finish the painting job its almost finish what do you think!

                    Comment

                    • upchurchmr
                      Senior Member
                      • May 2009
                      • 2518

                      #55
                      Re: Designing a new CONCRETE BOAT

                      Are you going to smooth out the gunwale? Might hurt getting in.

                      Comment

                      • germanhiguerav
                        Junior Member
                        • Aug 2017
                        • 20

                        #56
                        Re: Designing a new CONCRETE BOAT

                        Of course sir!
                        Originally posted by upchurchmr
                        Are you going to smooth out the gunwale? Might hurt getting in.

                        Comment

                        • germanhiguerav
                          Junior Member
                          • Aug 2017
                          • 20

                          #57
                          Re: Designing a new CONCRETE BOAT

                          https://youtu.be/IvjQb1LwcG0 THERES A VIDEO OF MY TEAM FLIPPING THE CANOE

                          Comment

                          • FishoutaFlorida
                            Senior Member
                            • Jan 2017
                            • 858

                            #58
                            Re: Designing a new CONCRETE BOAT

                            ...and here is a video of a competition.

                            “Perpetual optimism is a force to live by.”

                            Colin Powell

                            Comment

                            • ahp
                              Senior Member
                              • Jan 2001
                              • 6107

                              #59
                              Re: Designing a new CONCRETE BOAT

                              Concrete cargo ships were built and used during WWI. They were not economical, too much weight for given payload. After WWI many of them were scuttled as breakwaters.

                              Comment

                              • upchurchmr
                                Senior Member
                                • May 2009
                                • 2518

                                #60
                                Re: Designing a new CONCRETE BOAT

                                This is a canoe by a group of college students.

                                Why are we talking about full sized ships?

                                Why don't we let these guys be the show, since it is their thread?

                                Comment

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