I am building a small ship (or very large sailboat) that will have a concrete ballast at the base of the keel. I am looking to increase the weight of the concrete (lb/ft3), but I also want to maximize the impact resistance of the concrete to resist cracking/shattering should the boat hit a rock hard vertically due to waves.
The simplified dimensions of the concrete portion of the keel will be 11.5" W x 18" D x 40' L. This will essentially be bolted on to the bottom of a laminated wood (fir) keel which is 11.5" W x 12" D x 40' L (simplified dimensions).
How can I determine the best concrete recipe and reinforcement scheme for this particular usage?
I need to determine:
- optimal size of rebar to use;
- optimal size(s) of aggregate;
- how many parts of cement, sand, and aggregate to mix;
- and the optimal amount of rebar to include.
In general heavier is better; I am not looking to lighten the concrete. I know concrete recipes are a topic all on their own; what I need is a recipe to start with that will produce a strong and heavy concrete that resists cracking from a heavy impact. The boat will displace 100 gross tones of water and may be subjected to waves with crest-to-trough wave height of about 6' in areas where there is an unlikely yet possible danger of striking underwater obstructions. It doesn't need to support being continuously jackhammered, but support get hit perhaps say 5 times over it's expected lifetime of say 20 years (just to give you an idea of infrequency). I am not planning to strike bottom, but it can and does happen despite all cautions taken.