Dale KG5U requested an recap of the answers to this question. Perhaps it
will
also be of interest to others.
------------------------------------------------------------------------------
I've got the same problem on some steps going down to my basement. The
concrete wasn't level and the individual steps sloped downward. I haven't
used it yet but a friend in the construction industry recommended
"hydraulic cement" (i think it was cement or maybe concrete.) I haven't
used it yet but plan to within the next couple of weeks. Might be
worth looking into
gl Greg kc4zv
------------------------------------------------------------------------------
well, some guys just have really lame concrete pours for bases...you as
someone looking to enhance your concrete pour sound like you are "going
professional"
Depending on how professional you want to get there is a really slick way to
go that is a lil pricey.
I know you live where the ground is rock, but I am sure you have seen them
driving concrete pilings to support high rise buildings.
Those pilings are never long enough in themselves to get deep enough to grant
the amount of support necessary to do the job....so, how do they get down to
terra firma (isn't that LU/F) well - they glue the pilings together end to
end....simple enough solution, eh? Glue!
There are two part commercial epoxies that you can butter on an existing
surface prior to adding another pour.
I would recommend you contact a supplier of concrete related chemical
products, easily found in the Yellow Pages - form releases are their main
stock in trade, but if an outfit supplies that they also will be selling
construction epoxies.
This is the super way-serious approach - since you only have probably 10 or
so sq ft of surface at the top of the current base it shouldn't be a lot of
goo that you need!
Your current situation in addition to being bad since it is standing water,
is standing water alongside the tower legs and you are wise to try and
eliminate it. Before you go to the pour be sure to coat the tower legs with
a coating, probably asphalt base (W3LPL what was it you used?) then proceed.
Get the height up there and trowel it a lot - this will make it no longer a
home for that water. The long session of trowelling will force the
concrete's coarse agregate (stones) deeper into the pour and the finer
components of the mix will rise - they are more condusive to a final product
that is smoother....and if you really wanna go all the way there is the
option of painting the concrete with waterproofing.....
Be sure to have the surface at a slight pitch so that it encourages the water
to run off the side of your pour. Of course after all this you have to have
some plastic letters and numbers to emboss a secret code into the pour....you
probably need some K's, 1's, V's, U's and T's....unless like myself you are
awaiting Gate Two!
73
Jim zx
------------------------------------------------------------------------------
Deleted your original post but wanted to make a comment. Commercial
tower installers use grout to fill in under leg pedestals and other non-load
bearing concrete applications. I don't think you need concrete; just
grouting a little cone up the leg should do it. And water will run off
automatically. After, that is, you tar the legs per previous comments
Just a thought.
73, Steve K7LXC
------------------------------------------------------------------------------
first ... i think the base you described is not per Rohn (or clone) specs..
but i've never heard of a base failure before so ... hey, what the heck!
I wish i could remember the name of the chemical (an etchant of some sort)
that is used to bond cold joints... just ask in the obvious concrete
circles.. it exists.
How about gitting a cheapo masonry drill and poke holes in your base and
insert short pieces of rebar in them, then lay more rebar across the surface
of the existing base and then pour, regardless of the bond? Water may
still get between the old and new no matter what you do. Cold joints are a
problem.
Could you just dig a drain and leave the base as it is? I'd bet that's the
best cure.
de KD7LS
------------------------------------------------------------------------------
If it's a smooth finished surface you'll need to rough it up. Chisel,
hammer, etc. the smooth surface. If it's rough then all you've got to do is
clean it REALLY good. Get out all the fines and chunks (same prep for the
removed smooth surface). Go down to your local cement place (or Home Depot)
and get some concrete adhesion enhancer (it looks like Elmer's
glue.....which one old coot cement guy said it really was....it's also
called Moose Milk) and liberally spread it on. Then pour the new cement on
top of it. It works.....we do it here at the power company when we have to
add on to existing concrete in our subs.
73 Gary K7FR
------------------------------------------------------------------------------
Many thanks for all your answers. If I missed recapping anyone's answer,
I apologize. I printed them all out and have them at home, but may have
lost some on this computer.
73, Dave Clemons K1VUT
|