Results 1 to 28 of 28

Thread: Silage clamp construction - any useful tips/hints appreciated!

  1. #1
    Junior Member
    Join Date
    Apr 2013
    Posts
    27

    Silage clamp construction - any useful tips/hints appreciated!

    Currently submitting planning for a 120ft x 40ft x 10ft silage clamp using 8" panels and RSJ's to allow for a roof at a future point. Its been sometime since we last did a clamp on this farm (previous ones are all timber sleeper design) so i just wondered whether anyone had any useful tips/things to avoid doing before we get final quotes.

    Obviously I know all the basic structural specs that are required (e.g. relevent British Standards, effluent tank reqs, base extending beyond walls etc), it was more a case of whether anyone had any good tips based on past experience. For example, how much fall should the base feature to allow good effluent drainage? Is 8" across 120ft enough or will it need over 1ft? What protective coatings should i be looking at using to avoid effluent attack? Best concrete mix?

    Any other tips or considerations greatly appreciated!

    Thanks

  2. #2
    Senior Member davidroberts30's Avatar
    Join Date
    Feb 2013
    Location
    pembrokeshire
    Posts
    1,184

    Re: Silage clamp construction - any useful tips/hints appreciated!

    can you use the silage fast enough from a 40ft face?

  3. #3
    Senior Member grassmanman's Avatar
    Join Date
    Apr 2013
    Location
    Northern Ireland
    Posts
    885

    Re: Silage clamp construction - any useful tips/hints appreciated!

    I saw one done recently where the guy had made the fall to the back of the silo and had sunk a half sewer pipe channel along the back wall to lay drainage pipe in which ran out to tank below side wall.
    Interesting idea as it meant effluent wasn't running towards you when using it and pipe wasn't getting trampled or moved when pit was being filled. Also floor was flat for bringing out feed.

  4. #4

    Re: Silage clamp construction - any useful tips/hints appreciated!

    What length concrete panels are you using? At 3000m high you are likely to be ok with 6inch single loading panels, as long as they have sufficient 9.3mm strand (don't get the panels made using 7mm wire).

  5. #5
    Junior Member
    Join Date
    Apr 2013
    Posts
    27

    Re: Silage clamp construction - any useful tips/hints appreciated!

    Quote Originally Posted by davidroberts30 View Post
    can you use the silage fast enough from a 40ft face?
    Grass silage is the only forage fed, so can get across the face in about 3-4 days. Existing pit is 40ft wide and never had any bother with secondary fermentation

    Quote Originally Posted by jousty View Post
    What length concrete panels are you using? At 3000m high you are likely to be ok with 6inch single loading panels, as long as they have sufficient 9.3mm strand (don't get the panels made using 7mm wire).
    Likely to go for 20ft panels Jousty. On one side the RSJ's will be to the outside of the panels but on the other side the panels will be inside the webs of the beams to allow for a double sided wall/mirror image clamp at a later date. So steel in contact with silage mig on one side - not ideal I know - what is the best option for treating the posts with to stop them rotting?

    Also, the regs state that the base and associated drainage channels must extend beyond the perimeter of the walls, but is there a minimum distance by which the base must extend? Or is it just a case of extending it by as much as is practically needed to get the relevent size drainage channel in?

    Trying to do it once and do it right!

  6. #6

    Re: Silage clamp construction - any useful tips/hints appreciated!

    For the sides of the silage clamp where you are only going to be loading from one side, you should look at 6 inch panels (single loading wire pattern 9.3mm strand) so you can keep costs down. For the side where you may potentially double load, we would normally do a 170mm panel as it fits nicely into a 203 x 203 column (8inch panels are too big). This means you have a relatively flush finish on both sides.

    For the exposed steels you would be best using galvanised steels, and then as an additional you can paint them with a rubber based paint.....this isn't essential but it certainly won't hurt. You'd be best speaking to a paint supplier about the best type of paint, a quick search on google should throw up a few options.

  7. #7
    Senior Member
    Join Date
    Feb 2013
    Posts
    116

    Re: Silage clamp construction - any useful tips/hints appreciated!

    Silage effluent will have galvanising off in a year, but don't know what effluent wont attack. Plastic coating mayby

  8. #8

    Re: Silage clamp construction - any useful tips/hints appreciated!

    Quote Originally Posted by jousty View Post
    For the sides of the silage clamp where you are only going to be loading from one side, you should look at 6 inch panels (single loading wire pattern 9.3mm strand) so you can keep costs down. For the side where you may potentially double load, we would normally do a 170mm panel as it fits nicely into a 203 x 203 column (8inch panels are too big). This means you have a relatively flush finish on both sides.

    For the exposed steels you would be best using galvanised steels, and then as an additional you can paint them with a rubber based paint.....this isn't essential but it certainly won't hurt. You'd be best speaking to a paint supplier about the best type of paint, a quick search on google should throw up a few options.
    what keeps these panels standing, is it simply the strength of the RSJs that they are slotted into ?

    say the clamp is 40ft wide and 10ft high, and the wall is 8ft high with an RSJ every 15ft I can't see an RSJ as being of sufficient strength to keep the concrete panel standing

  9. #9
    Senior Member
    Join Date
    Feb 2013
    Posts
    101

    Re: Silage clamp construction - any useful tips/hints appreciated!

    I have yet to be conviced with panels for silage walls as its the RSJ's that hold it altogether. The last pit I saw with panels had to be back filled with clay to add support. Around here, nearly all silo's or slurry tanks are shuttered with the walls tied into the floor. You don't have to worry about efluent corroding the steel RSJ's either.

  10. #10

    Re: Silage clamp construction - any useful tips/hints appreciated!

    The side with the columns behind the panels will be fine. One the other side which has potential double loading, I would seriously consider shuttering reinforced concrete walls including encasing the columns. Yes it may cost a bit more but you know it will last forever.

  11. #11

    Re: Silage clamp construction - any useful tips/hints appreciated!

    The panels are slotted into the web of the steel, or clamped onto the front face. The RSJs are then acting as support for the panels, and the silage is loaded against the panels. It is a fairly standard construction method and you just need to make sure that the panels lengths, thicknesses, and RSJs (including foundations) are designed suitably to allow for the loads....the higher you go, the thicker the panel, and the shorter panels lengths you require. Agricultural clamps we do tend to be from 2500mm to 4000mm high and panels thickness will either be 150mm or 180mm, and lengths from 15ft to 20ft. In terms of protecting the steels (we just supply the panels), from the jobs we have seen the majority of people just go with galvanised steels and I have not heard of any complaints, but it would seem sensible to add a protective paint to improve lifespan.....this is not my area of expertise so probably best to discuss with the steel supplier.

    In terms of slurry we would not recommend using the same method (you don't want steels anywhere near), you would normally use the panels vertically (cantilever panels or cast in L shapes) and tied into the floor slab....this gets away from the need for supporting steels, but the construction method takes a lot more work. This can be backfilled but is not essential.

    There are some pictures of clamps on here which will give you a better idea.
    http://www.jpconcrete.co.uk/silage_clamp.htm

  12. #12
    Senior Member
    Join Date
    Feb 2013
    Location
    Northumberland
    Posts
    131

    Re: Silage clamp construction - any useful tips/hints appreciated!

    Quote Originally Posted by davidroberts30 View Post
    can you use the silage fast enough from a 40ft face?
    I have 2 40ft clamps side by side with a pre-cast t-shaped wall between them that's set (and reinforced) into the floor. I was thinking of taking it out as I reckon the saving in waste from 2 less edges would outweigh slower progress over the face. I clear the 40ft face in 2 days at the moment.

    The whole thing is roofed (nothing connected to central wall) and I take a lot of care in filling and sheeting the pit - the contractor is encouraged to bring the old, back-up machine. What do people think? I thought I'd make a better job filling the 2 outsides from a wider centre as well. Could fit a bit more in with a higher crown as well...

  13. #13
    Junior Member
    Join Date
    Feb 2013
    Posts
    25

    Re: Silage clamp construction - any useful tips/hints appreciated!

    Quote Originally Posted by e3120 View Post
    I have 2 40ft clamps side by side with a pre-cast t-shaped wall between them that's set (and reinforced) into the floor. I was thinking of taking it out as I reckon the saving in waste from 2 less edges would outweigh slower progress over the face. I clear the 40ft face in 2 days at the moment.

    The whole thing is roofed (nothing connected to central wall) and I take a lot of care in filling and sheeting the pit - the contractor is encouraged to bring the old, back-up machine. What do people think? I thought I'd make a better job filling the 2 outsides from a wider centre as well. Could fit a bit more in with a higher crown as well...
    They seem to be a bit out of fashion now but a ramp makes packing a pit a lot easier IMO and a lot easier to get more into the pit. We store bales on the silage and i find you can get the pit a lot more level as well. A lot of silage pit in by contractors use a dorset wedge round here and the pits could take an extra 15% and runs up in a huge wedge.

  14. #14

    Re: Silage clamp construction - any useful tips/hints appreciated!

    Quote Originally Posted by e3120 View Post
    I have 2 40ft clamps side by side with a pre-cast t-shaped wall between them that's set (and reinforced) into the floor. I was thinking of taking it out as I reckon the saving in waste from 2 less edges would outweigh slower progress over the face. I clear the 40ft face in 2 days at the moment.

    The whole thing is roofed (nothing connected to central wall) and I take a lot of care in filling and sheeting the pit - the contractor is encouraged to bring the old, back-up machine. What do people think? I thought I'd make a better job filling the 2 outsides from a wider centre as well. Could fit a bit more in with a higher crown as well...
    Sounds like a good plan, can't see any need for the dividing wall now if your using the face in 2 days. Get the stile saw out....

  15. #15
    Member beeker's Avatar
    Join Date
    Feb 2013
    Location
    ayrshire
    Posts
    83

    Re: Silage clamp construction - any useful tips/hints appreciated!

    hi jousty,

    I've got a pit with rsj's 356x165 at 15'

    currently panels are 3m high, but was wanting to put another metre or 1.2m panel on top for more capacity. are my rsj's big enough?

    cheers

  16. #16
    Member Agri Design's Avatar
    Join Date
    Feb 2013
    Location
    Ayrshire
    Posts
    66

    Re: Silage clamp construction - any useful tips/hints appreciated!

    Quote Originally Posted by beeker View Post
    hi jousty,

    I've got a pit with rsj's 356x165 at 15'

    currently panels are 3m high, but was wanting to put another metre or 1.2m panel on top for more capacity. are my rsj's big enough?

    cheers
    beeker

    As you are in Scotland a building warrant would be required for this work as its structural.

    Looking at a similar job with structural design by a structural engineer has it at 457x191 at 4 m high. The steel size is not the only issue the foundation will probably be undersized too. If you would like to discuss the issues give me an email or call.

    David
    Agri Design
    Agri Design specialise in the design of agricultural buildings.

  17. #17
    Member beeker's Avatar
    Join Date
    Feb 2013
    Location
    ayrshire
    Posts
    83

    Re: Silage clamp construction - any useful tips/hints appreciated!

    Quote Originally Posted by Agri Design View Post
    beeker

    As you are in Scotland a building warrant would be required for this work as its structural.


    David
    Agri Design

    well considering it got built from new without any warrants, I don't think that'll be happening


    the rsj's are 1.2m deep with around 3 m3 of concrete each

  18. #18
    Senior Member
    Join Date
    Feb 2013
    Posts
    192

    Re: Silage clamp construction - any useful tips/hints appreciated!

    looking at this thread with interest, as looking at extending my silage pit, as taking away a side and back soil wall which is to low and replacing with 15ft by 8 ft, 6 inch panels, so what size girders do i need and how deep and what concrete mass they need around em??

  19. #19
    Senior Member
    Join Date
    Feb 2013
    Location
    dorset
    Posts
    336

    Re: Silage clamp construction - any useful tips/hints appreciated!

    don't have excess rsj poking above panels, will get on your tits when sidesheets get ripped every 15/20 ft as clamp fills.....only a small point but easy to plan now than swear later

  20. #20
    Junior Member
    Join Date
    Apr 2013
    Posts
    27

    Re: Silage clamp construction - any useful tips/hints appreciated!

    Thanks for the replies so far, some useful advice here.

    Had a quote for a shuttered concrete wall pit which puts an interesting perspective on things.

    How long should the concrete be left to cure to get up to full strength before filling with silage? Timescale is going to be tight to get it through planning and in place by the end of May

    Also, may seem like a daft question, but for those of you with concrete panel or shuttered wall clamps, what is the easiest way of securing side sheets the full length of the walls? Present clamps are timber sleeper walls so we simply tack the sheets to the timbers using folded-up 25kg plastic bags to add strength/prevent the sheet splitting where the tack is put in. Obviously cant do that with concrete, so whats easiest way when there is nothing to nail or tie to, particularly on a shuttered clamp? Scrunching the sheet up, tie a tyre on and hang it over the wall?? Tie onto the safety rail and weight down at the base to stop it flapping around??

  21. #21
    Senior Member grassmanman's Avatar
    Join Date
    Apr 2013
    Location
    Northern Ireland
    Posts
    885

    Re: Silage clamp construction - any useful tips/hints appreciated!

    Quote Originally Posted by no land farmer View Post
    Sounds like a good plan, can't see any need for the dividing wall now if your using the face in 2 days. Get the stile saw out....
    Uncovering after 1st cut to then have to recover it all again after 2nd. 80ft wide not fun.

  22. #22
    Senior Member
    Join Date
    Feb 2013
    Location
    Northumberland
    Posts
    131

    Re: Silage clamp construction - any useful tips/hints appreciated!

    Quote Originally Posted by grassmanman View Post
    Uncovering after 1st cut to then have to recover it all again after 2nd. 80ft wide not fun.
    That was in my mind too, but we currently don't uncover it all each cut so would do the same. Never works out with 1 filled at end of a cut (take 3/4 + wholecrop) As it's covered with bales, it's the sides that take longest (putting them lengthways gives best seal) and I would have less of these.

    The days of stihl-sawing do not appeal!

    No sidesheets used here. If I roll close enough to wall they just get torn with wheels. Find that precisely placed bales down sides can make good seal - extra few inches higher walls makes this much easier. There is a bit of waste where the panels join - shuttered walls would eliminate this.

  23. #23
    Member Agri Design's Avatar
    Join Date
    Feb 2013
    Location
    Ayrshire
    Posts
    66

    Re: Silage clamp construction - any useful tips/hints appreciated!

    Quote Originally Posted by early riser View Post
    Thanks for the replies so far, some useful advice here.

    Had a quote for a shuttered concrete wall pit which puts an interesting perspective on things.

    How long should the concrete be left to cure to get up to full strength before filling with silage? Timescale is going to be tight to get it through planning and in place by the end of May
    early riser

    The longer you can leave it the better. 4 weeks would be a good length on time to allow the concrete to reach most of its strength. If its filled to early it isn't good for the longevity of the clamp. If you coat the concrete that helps but some coating require the concrete to go off first before applying. Time constraints always seem to be a problem for silage clamps.

    For anyone else needing a new clamp next year now is the time to act. Planning can take 2 months or so with a further 2 months to build say and one more to cure. Also builders can become busy with everyone needing clamps finished at that time of year.

    Some further info on my website.
    http://www.agri-design.co.uk/home/sl...-silage-clamps

    David
    Agri Design
    Agri Design specialise in the design of agricultural buildings.

  24. #24
    Senior Member
    Join Date
    Feb 2013
    Posts
    480

    Re: Silage clamp construction - any useful tips/hints appreciated!

    Quote Originally Posted by danpwll View Post
    looking at this thread with interest, as looking at extending my silage pit, as taking away a side and back soil wall which is to low and replacing with 15ft by 8 ft, 6 inch panels, so what size girders do i need and how deep and what concrete mass they need around em??

    Stuart will be able to sort you out on the girders assuming you're using his panels.

  25. #25

    Re: Silage clamp construction - any useful tips/hints appreciated!

    Quote Originally Posted by beeker View Post
    hi jousty,

    I've got a pit with rsj's 356x165 at 15'

    currently panels are 3m high, but was wanting to put another metre or 1.2m panel on top for more capacity. are my rsj's big enough?

    cheers
    Afraid I am the wrong person to ask, you would need a structural engineer. I would say that if the panels are 150mm thick then going 4200mm would not be advisable, you would need a thicker panel, and you'd need to get someone to look at the steels and foundations.

  26. #26
    Member Agri Design's Avatar
    Join Date
    Feb 2013
    Location
    Ayrshire
    Posts
    66

    Re: Silage clamp construction - any useful tips/hints appreciated!

    The piece of mind by having a structural engineer design the structure in my eye is worth every penny, not that the cost should be that much. normally in the hundreds rather than thousands of pounds.

    I would talk to the likes of McColm Civil & Structural Engineers to get a cost for structural design. They work throughout the UK I believe.
    They are familiar with agricultural work, which is a must when dealing with engineers as the costs and designs can become over the top if they are not familiar with the correct regulations and requirements.

    If you give them a call let them know you got their name from here.

    David
    Agri Design
    Agri Design specialise in the design of agricultural buildings.

  27. #27
    Senior Member
    Join Date
    Feb 2013
    Posts
    192

    Re: Silage clamp construction - any useful tips/hints appreciated!

    Quote Originally Posted by RED BULL View Post
    Stuart will be able to sort you out on the girders assuming you're using his panels.
    ye, just looking about what size steel i need or see what price mass concrete would be?

  28. #28
    Senior Member
    Join Date
    Feb 2013
    Posts
    480

    Re: Silage clamp construction - any useful tips/hints appreciated!

    Quote Originally Posted by early riser View Post
    Also, may seem like a daft question, but for those of you with concrete panel or shuttered wall clamps, what is the easiest way of securing side sheets the full length of the walls? Present clamps are timber sleeper walls so we simply tack the sheets to the timbers using folded-up 25kg plastic bags to add strength/prevent the sheet splitting where the tack is put in. Obviously cant do that with concrete, so whats easiest way when there is nothing to nail or tie to, particularly on a shuttered clamp? Scrunching the sheet up, tie a tyre on and hang it over the wall?? Tie onto the safety rail and weight down at the base to stop it flapping around??
    You could still nail to timber by putting a timber either directly on top of the concrete wall or a bit higher underneath the safety rail.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •