Road Cycling - frame material

i am planning on upgrading my road bike this fall

i am a fairly decent size guy 6ft 205 lbs and tend to really pound the pedals

what type of frame material stands up best to heavy use?

i will not race but will enter the odd triathlon...probably put 3-4k miles on it per year

i am leaning towards good old fashioned steel ... i want something that will last a while and will stand up to my cycling style..is this the best choice??? it can be pretty wet around my parts...corrosion could be a factor as well

Steel is a good choice will last a long time.. Another good choice would be titanium but is quite a bit more expensive. In general any good bike will stand up to alot of heavy use, steel, aluminum, scandium, Carbon and Ti.

Steel is a very good choice-probably the best choice. Rust is not a problem if you treat the inside with FrameSaver and put on a good quality non-abrasive non-cleaning auto wax; and if you nick the paint make sure you touch it up as soon as possible. I have a 18 year old bike that has no rust at all and never been treated but has been waxed; and I have a 24 year old that sat outside for 5-6 years along the coast in all sorts of weather, and I rode it on the beach with the salt water getting all over it; it now sits in the rafters in the garage in total disrepair but there is only minor surface rust on it-and this bike has NEVER been treated or waxed! Sheldon Brown lives in Boston and commutes to work sometimes on a steel bike made in 1916 and he ain't worried about the rust!!!!

For a big strong racer type guy, you will need a stiff frame. I'm a steel frame rider, but I think there are advantages for big guys in using Al. They dont just break, they are very stiff, and not too heavy.
I wouldnt recomend Al for a small rider, since the small Al frames are overly stiff, steel would be a better choice.
If you can afford a nice Ti frame , you wont be sorry, but Al tends to be good value.

design and fit should be greater priorities for this new bike.
After that you can debate teh merits of the different materials but for a heavy rider. large diamter AL tubes holds manu benefits. something like a CAAD7 will do nicely