concrete docks
Mike Sullivan
advantages?
disadvantages?
Charles Carroll
We have to buy a new dock, too. There has been lot of talk about what kind
of dock we should purchase.
I asked why we just didn�t get a concrete dock like the ones the other slips
have. �Too high to pull up to,� was the answer I got.
I looked around. The docks in our Marina are very nice and appear quite
durable. But you certainly couldn�t pull up next to one in a single and
slide a rigger across it. They are just too high.
Cordially,
Charles
Mike Sullivan
might make one that floats at a level for rowing.
I couldn't find any, that's why I was asking.
Thanks
"Charles Carroll" <charles...@comcast.net> wrote in message
news:7p01mn...@mid.individual.net...
> Mike,
>
> We have to buy a new dock, too. There has been lot of talk about what kind
> of dock we should purchase.
>
> I asked why we just didn�t get a concrete dock like the ones the other
> slips have. �Too high to pull up to,� was the answer I got.
>
> I looked around. The docks in our Marina are very nice and appear quite
> durable. But you certainly couldn�t pull up next to one in a single and
karon
wrote:
> Anybody use concrete docks? Modular or otherwise?
>
> advantages?
>
> disadvantages?
We have concrete at Maidenhead - you can see them on the webcam
www.maidenheadrc.org.uk - click on Webcam ,and browse through
'previous pics' - the images change every few minutes. (might be a bit
snow covered at the moment though!)
Personal view is that they are fine, and not to high for singles -
I've had more problems with those big black plastic 'cubes'. THey are
very hard on the spoons though, although someone suggested that we
coukd clad the concrete in wood. If you need pictures from closer up,
let me know, and I will get them for you.
Karon
carolinetu
advantages:
1. You can configure them to make whatever size and shape suits your
location
2. You can tow them to other locations if required, e.g. we lend part
of ours to Weybridge Ladies for their regatta.
3. The geese and swans don't like them, so you don't get any c**p on
them.
Caroline
Phil
We have concrete 'floats' bolted to a steel frame clad in wood.
Entirely DIY. They have enough mass/displacement so they don't tip
much when launching an eight, and are at a good height.
The floats are made about 3' x 2' x 2' from small chicken wire on a
polystyrene block with your anchor bolts pushed in. Chicken wire then
acquires a couple of coats of cement mortar to about 1.5" thick. 8
floats to a pontoon section.
If you are interested in DIY (certainly low materials costs) I can
take some better measurements/photos and details (they sort of
'evolved' in construction)
Phil.
Edgar
"carolinetu" <carol...@aol.com> wrote in message
news:06098a6e-407e-495c...@s19g2000vbm.googlegroups.com...
can check, but I seem to recall that there is nothing at the edge that you
can get hold of with your fingers to hold your boat in while you sort
yourself out. If there is nobody to hold your riggers it is hard to stop
the boat sliding off while you stand up to get out.
It may be just a peculiarity of one particular maker.
A wooden and also concrete pontoons usually have a handy strip of wood
running along the edge which makes a handhold.
carolinetu
the edge of ours.
Charles Carroll
> them.
Caroline,
What? Weybridge birds refuse to c**p on a plastic dock!
How elitist! How snobbish! How typical of you Brits!
In the States our birds are much less discerning. They c**p everywhere. On
our plastic docks! On our Carl Douglas shells! One even flew over me while I
was sculling and c**p'd square on my pate. Arrrrrgh!
Would that our birds had the good manners of yours!
Cordially,
Charles
David Jillings
Maybe another snag with Shimano shoe clips (see other thread) would be
the c**p transportation problem. And we get dog s**t too :o)
David.
Charles Carroll
I was talking to David Lay this morning about concrete docks.
Never shy about expressing an opinion, David says that concrete docks are
far superior to the plastic dock we have now. He says that they are cheaper
to build, cheaper to maintain, and much more durable.
Below is a link to a website that is right across from OWRC. According to
David, Aquamaison will build a dock to any set of parameters you request.
Might be worth checking out.
http://www.aquamaison.com/contact.asp
Cordially,
Charles
Ps. I asked David why the Club just doesn�t ask Aquamaison to build a new
dock for us. David said he was told, �Because we have always had a plastic
dock.� That kind of answer is designed to drive an engineer up a wall.
Mike Sullivan
There isn't any link on their page for docks, I'm sure they'd do them but
I'd like to see the designs.
It's probably too late for the program I'm talking to, but I'm curious for
the future.
Mike
"Charles Carroll" <charles...@comcast.net> wrote in message
news:7p2fri...@mid.individual.net...
> Mike,
>
> I was talking to David Lay this morning about concrete docks.
>
> Never shy about expressing an opinion, David says that concrete docks are
> far superior to the plastic dock we have now. He says that they are
> cheaper to build, cheaper to maintain, and much more durable.
>
> Below is a link to a website that is right across from OWRC. According to
> David, Aquamaison will build a dock to any set of parameters you request.
> Might be worth checking out.
>
> http://www.aquamaison.com/contact.asp
>
> Cordially,
>
> Charles
>
> Ps. I asked David why the Club just doesn�t ask Aquamaison to build a new
> dock for us. David said he was told, �Because we have always had a plastic
> dock.� That kind of answer is designed to drive an engineer up a wall.
Charles Carroll
The houseboat that Liz�s sculls past in the video sits on a concrete
platform built by Aquamaison.
http://www.youtube.com/watch?v=kl9HRWvozSA
I am not familiar with the nomenclature, but David calls the platform a
dock.
Cordially,
Charles
Charles Carroll
>their c**ps.
So David,
Do you really mean to suggest that Molesey serves as a kind of WC for
Weybridge? Is Molesey where all the swells go to c**p?
Speaking of "swells" puts me in mind of a little story Steve Fairbairn tells
at the end of the rowing chapter in "Fairbairn of Jesus" (see below).
Cordially,
Charles
--------------
Fairbairn's little story:
Tom Hockin, with his white hair and loud voice, had more stories about him
than there were about anyone else.
On one occasion he was sculling on the Cam and his scull hit some loose ice
and he fell out. He went into a pub close by to get warm. Two navvies were
standing in front of the fire, he pushed them aside and stood in the middle.
One navvy remonstrated.
"Go to hell!" said Tom.
"I've been there," the navy replied.
"What's it like?"
"Pretty much the same as here, the big swells get all the fire."
donal...@gmail.com
recently and enclose a response below which may be of some assistance.
Ive loads of sites for self build pontoons in the states which looked
quite interesting and can send links if you like.
In the end we bought 2 secondhand pontoons with steel frame wooden
boards and polystyrene floats though we may upgrade the floats at some
future point. These look like they should do the job but havnt popped
them in the water yet!!.
Regards
Donal
"The boat show pontoons quoted have a nominal freeboard of 450mm. The
only pontoon we do with a 250mm freeboard is a purpose built rowing
pontoon 9m x 2.5m with a brush concrete surface. These would have to
be new and cost £3500 ex works + VAT & delivery . Lead time 8 to 10
weeks.
NB This does not include for mooring pile brackets which would cost
£500 each. ( Piling by others).
Regards
Ken Limburn
Estimating Manager
Walcon Marine Ltd
Cockerell Close
Segensworth West
Fareham , Hants
PO15 5SR
Tel: 00 44 1489 579977
Fax: 00 44 1489 579988
donal...@gmail.com
Is there a web resource giving maximum recorded river flow rates and
heights of flood.(am particularly interested in River Avon Wiltshire).
Also looking for calculations for stiff arm design which will utilise
the above information.
Cheers
Donal
Carl Douglas
Are you talking here about the forces generated by the current on
floating docks, Donal?
Cheers -
Carl
--
Carl Douglas Racing Shells -
Fine Small-Boats/AeRoWing Low-drag Riggers/Advanced Accessories
Write: Harris Boatyard, Laleham Reach, Chertsey KT16 8RP, UK
Find: http://tinyurl.com/2tqujf
Email: ca...@carldouglas.co.uk Tel: +44(0)1932-570946 Fax: -563682
URLs: www.carldouglas.co.uk (boats) & www.aerowing.co.uk (riggers)
donal...@gmail.com
> donal.ca...@gmail.com wrote:
> > Regarding pontoon design.
>
> > Is there a web resource giving maximum recorded river flow rates and
> > heights of flood.(am particularly interested in River Avon Wiltshire).
>
> > Also looking for calculations for stiff arm design which will utilise
> > the above information.
>
> > Cheers
>
> > Donal
>
> Are you talking here about the forces generated by the current on
> floating docks, Donal?
>
> Cheers -
> Carl
> --
> Carl Douglas Racing Shells -
> Fine Small-Boats/AeRoWing Low-drag Riggers/Advanced Accessories
> Write: Harris Boatyard, Laleham Reach, Chertsey KT16 8RP, UK
> Find: http://tinyurl.com/2tqujf
> URLs: www.carldouglas.co.uk(boats) &www.aerowing.co.uk(riggers)
Hi Carl
yes Im seeing if its practicable to consider stiff arms and chains
locking a docks position rather than piles - costing the differences -
also from a planning perspective stiff arms are less obtrusive in the
countryside.
Regards
Donal
Carl Douglas
Hmmm. It all depends, doesn't it?
First there's the frontal area of your docks. I'm assuming they're
rectangular boxes with bluff ends, giving a high frontal drag
coefficient, Cdf of say 2.
If you know the maximum flow velocity, and the frontal area, Bernoulli
can help you there: P = rho x v^2/(2 x g)
So if v = 3m/sec, rho (density) = 1 tonne/m^3, g = 9.81 m/sec^2, then:
Face pressure ~= 0.5 tonne force/m^2
Now multiply by the fudge factor, Cdf = 2, so:
Face pressure = 1 tonne force/m^3
Then there's skin friction. If the dock is as long as an eight, then as
a 1st approximation assume the skin friction drag per unit surface area
is similar to that of an eight at the same velocity. For an eight
moving at ~6m/sec the skin friction drag is about 10kg force/m^2, so say
about 3kg force/m^2 at 3m/sec, Now double that to allow for the awkward
concrete surface & crummy shape, giving you 0.006 tonne force/m^2 of
surface.
If the dock is 15m long by 3m wide by 0.5m deep in the water, my first,
very crude, stab at the fluid drag would be:
Drag, D =(3 x .5 x 1) + ((3 + 2 x 0.5) x 15 x 0.006)
[frontal] [skin drag]
= 1.86 tonne force
Obviously you need a safety factor to allow for collecting driftwood &
impacts from stray vessels - say multiply that figure by a factor not
less than 3. But if the depth is only half of that indicated, the load
falls close to 1 tonne.
Or you could think of a number & double it ;) I'd guess that something
able to take a 10 tonne load without moving should do the job
handsomely, but there's no warranty on that statement, nor on any of the
above calcs.
Cheers -
Carl
PS Had you heard, BTW, that the British Rowing exec has told its safety
& competition committees that they, the exec, have decided for them who
should be their chair-persons, & done so without even bothering to say
who they had chosen. So much for independent thought under that
expensive rebranding - Stalin would've been proud of 'em. The job of
the BR committee member is to rubber stamp whatever/whoever the
executive says or wants.
C
--
Carl Douglas Racing Shells -
Fine Small-Boats/AeRoWing Low-drag Riggers/Advanced Accessories
Write: Harris Boatyard, Laleham Reach, Chertsey KT16 8RP, UK
Find: http://tinyurl.com/2tqujf
donal...@gmail.com
Donal
> URLs: www.carldouglas.co.uk(boats) &www.aerowing.co.uk(riggers)- Hide quoted text -
>
> - Show quoted text -