# Forum Home Renovation Retaining Walls  Materials for retaining wall?

## Wes2008

Hi guys, 
I am living in Melbourne.  I want to build a retaining wall.  I am not sure what this material is called.  I am looking for this iron (metal) pole that has a "H" shape that stick into the ground and to hold the timber retaining wall.  Anyone know where I can find this? 
Thank you. 
Cheers,
Wes

----------


## bitingmidge

At your local railway station??  :eek:  
P

----------


## namtrak

Its called different things by different people, but if you go to your nearest Steel manufacturer and ask for lengths of 'I' section you shouldn't go to far wrong.  Remember to get enough to go at least 400 into the ground.  They'll cut it to length for you (around $30 per metre I think) - its a bugger to cut with an angle grinder I can tell you. 
You may also need, wait for it......... 'C' section which goes at the end of the retaining walls.

----------


## Gumby

I pulled down my old sleeper wall. No matter how good the timber, it eventually needs to be replaced at some point in the future. I replaced it with the link wall system :  http://www.australbricks.com.au/vic/product.php?ID=27 
The blocks are easy to install, once you have the base level. It saves digging post holes which were almost impossible here with the amount of rock in the ground. This systems isn't the cheapest option but I didn't have much choice and it will be there forever.

----------


## Eastie

Make sure it is hot dipped galvanised steel "I" beam" or "C" section. How deep it must go depends on soil type and wall height. 400mm deep sounds fine for a 400mm high wall in normal/heavy soil. In essence the deeper you go the better the wall (within reason). It's not uncommon to go almost 1:1 including a pad footing for walls up to 1m.  
Sleepers done with steel offer the added benefit that if the timber rots, all you need is a couple of high lift jacks and a chainsaw to fix it. Lift the above sleepers with high lift jacks, cut out the rotten/failed sleeper, drop down the jacks, insert new sleeper on top of the wall (it's almost that easy if you build the wall properly to start - ie. using steel soldiers).

----------


## himzol

> I pulled down my old sleeper wall. No matter how good the timber, it eventually needs to be replaced at some point in the future.

  I did exacly the same thing. 
By the time wood needs replacing (and it will need replacing) I don't know what sort of physical shape I'm going to be in, and whether I'll be financially well off enough to pay for it to be done.

----------


## Wes2008

Hi guys, 
I have looked around, searched the internet, called up a few metal manufacturer etc. and can't find one metal manufacturer sell "I" section.  Maybe because I am not in the industrial and looking at the wrong the place.  Can anyone please advise on where I can find "I" section for retaining wall or where to look for?  I don't mind travel anywhere in Victoria to pick it up, at this stage I am quite desperate to get a hand on it. 
Any advice would be greatly appreciated. 
Thank you so much! 
Cheers,
Wes

----------


## vsquizz

Call Sims Steel or look here:  http://www.steelweb.info/310UC158.htm 
also look under Universal Beam, not just Universal Column.  
Cheers

----------


## Dan_574

As per the previous post, it's called UB (universal beam), it comes in sizes from about 150mm right through to about 400+. universal column(UC) is more square in shape, but is more or less the same thing. In Victoria you can try Surdex Steel and I know for a fact Central Steel in Campbellfield has it in gal. It is very common and any steel merchant will have it or be able to get it in. For what you want in a retaining wall, try 100UC14.8 or 150UB14. The number at the end relates to weight in kg per metre.

----------


## IanA

Wes, 
How high is this wall going to be?

----------


## Wes2008

Max height would be 500 mm.  Someone told me that any higher, I would require engineer to design/approve it.   I didn't have the budget to pay for engineer so I stick with 500 mm.

----------


## soundman

I strongly agree with previous posters. Timber is only fit for "tempoary" retaining walls. I my travels arround town I pass at least half a dozen serious cases of biodegrading timber retaining walls.
Metal rusts, timber rots, it doesn't matter how big it is, and it happens much much faster than you think.
Masonry is for ever, ask an archiologist. Egiptians, Romans, Inkas
cheers

----------


## vsquizz

1 metre reconstitued limestone blocks should be about $40.00 a block laid or even cheaper depending on how much backing and earthworks need to be done.  Its a 100 hundred year structural wall done properly.   
For Most  councils a Retaining wall only requires engineers certification over 1 metre although councils may require a site plan to be submitted on walls over 600 mm and depending on the location.  A company installing these walls will have engineer approved structural detail drawings. 
1000 x 350 x350 blocks are currently around $17.50 each retail and require a Bobcat or excavator to lay them.  You can buy smaller blocks which can be laid by hand. 
Why not look at the fake post and panel system exactly like what you are planning but in concrete or reconstitued stone.  Once the "Universal Beam"  posts are in its a matter of sliding in the panels.  Again, easy to instal once you have the posts set.  A better long term solution but don't be put off if timber is the way you want and you have a pile of cheap sleepers....whatever turns your crank :Cool:   
Cheers

----------


## namtrak

> Max height would be 500 mm.  Someone told me that any higher, I would require engineer to design/approve it.   I didn't have the budget to pay for engineer so I stick with 500 mm.

  Just ring the local council regarding height restrictions to check - that way you will know for certain and it's the sort of knowledge that makes you top sausage at a BBQ. 
The height here is 800mm, which is 4 standard blocks. 
Cheers

----------


## IanA

Wes, 
Here in Vic any retaining wall over 1m high requires  a building permit, and therefore engineering computations. At 500mm high you are in the clear to do your own thing, and a failure of the wall at some future date is not going to be a major catastrophe. 
Eastie has given some good advice on the rule of thumb for 1:1 for depth of footings. 
Materials are as varied as the number of hot dinners you've had. Look around and see what takes your fancy and suits your pocket. Your personal style of garden may give some clues. Visit your local library and have a look at what they have on gardens and landscaping.

----------


## namtrak

> Wes,  
> Eastie has given some good advice on the rule of thumb for 1:1 for depth of footings.

  Im not so sure about the 1:1 footings, I think the depth of the footing relates more to the load behind the wall.  Also suspect that when you start getting footings over probably 600mm then they aren't achieving much.  You dont have to go far to see retaining walls at 2m high and Im pretty sure that the footings for those aren't 2m deep.  However I have been proven wrong before   :Frown:

----------


## IanA

Namtrak, there are many factors that influence the design of retaining walls and the design solution will reflect these. These will include the engineering properties of the soil at the base of the wall as well as the fill material behind the wall, and the behaviour of both soils when wet.
They can be designed as gravity structures, in which the mass of the wall and the breadth of it's base resists soil pressure behind the wall, in this case the footings may be relatively shallow. 
Other methods include universal sections used as piles, soil anchors, or a combination of both. 
For low walls, like the one that Wes is proposing, it would be costly have the soil tested at a lab and then to go through the full structural design, hence the 1:1 rule of thumb.

----------


## Wes2008

Hey guys,  
I would like to thanks for all the help/advices you guys have given me.  I ended up getting the Universal Column from Smorgon Steel.  And they were very helpful.  I will be getting the treated pine sleeper from Import Tile.  I am glad that I found what I was looking for. 
Once again thankyou very much. 
Cheers,
Wes

----------


## Eastie

What is above is very much a 'rule of thumb' - applied to walls upto 1m (with a normal bearing load above the wall = 5kPa, e.g. your not parking cars on it).    
For example a 600mm high wall has a common engineering spec of 500mm concrete footing in clay or 800mm concrete footing in sandy soil.   
For walls higher than 1.2m engineering specs start to vary more (i.e. 1500 high wall = 1300mm footing in clay or 1700mm footing in sand / 1800 high wall = 1800mm in clay or 2000mm in sand).  
1:1 is a rule of thumb, and if you've got free draining sandy soil it generally pays to go deeper to increase the bearing capacity.  In any instance for walls above 1m you should check with your engineer  :Biggrin:

----------


## Gingermick

> For walls higher than 1.2m engineering specs start to vary more (i.e. 1500 high wall = 1300mm footing in clay or 1700mm footing in sand / 1800 high wall = 1800mm in clay or 2000mm in sand).

  We allow a 300mm footing for the bigger walls we design. (keystone type) Just to stop the bricks from sinking not to add stability to the wall. This is achieved through a geogrid that is locked to the blocks and goes back on approximately a 1:1 ratio. (Dependant on soil type and load and height)
mick

----------


## Eastie

Yep - forgot to mention that is for steel/timber soldier sets - not blocks.

----------

