Advice???! High retaining wall in leca but how on earth do we deal with the backfill???
Would be incredibly grateful if someone could give us some good advice!!! Building a high retaining wall in leca (3 meters high at the highest point and then 'sloping' down to about 1 meter at the lowest height). The wall is according to all the rules of construction. Beside the wall, there will be a staircase made of block steps and the wall will only be backfilled on one side.
Now our problem!! What materials can we use for the backfilling?
Solution 1: Initially, we had a wild idea to use leftover lightweight concrete (we have tons of it) and stack it up at the bottom on a bed of gravel and then on top of the lightweight concrete, fill with crushed stone, and then setting sand for the block steps in the staircase. Would it even be possible to do so? Perhaps, for example, if one casts on the lightweight concrete? OK, maybe not a great solution, risk perhaps of the lightweight concrete freezing and breaking, but it would solve two problems for us (getting rid of excess building material + avoiding having to bring in 30 cubic meters of crushed stone).
Solution 2: Gravel (16-32) at the bottom 40 cm, geotextile, existing fill material (mostly consists of stones of various sizes + sand & a little soil - so not suitable for anything to grow in, so it can't be used for anything where something needs to be planted), and finally about 30 cm of crushed stone of finer dimension and on top of this, the block steps. The question here is how to ensure that the existing fill material doesn't settle over time making the staircase uneven?? The staircase adjoins one side to the retaining wall and the other side to a slope.
Solution 3: Clearly the most expensive!! Buy 30 cubic meters of gravel or similar and fill up with and place the block steps on that.
Does anyone have any thoughts? Advice?
Now our problem!! What materials can we use for the backfilling?
Solution 1: Initially, we had a wild idea to use leftover lightweight concrete (we have tons of it) and stack it up at the bottom on a bed of gravel and then on top of the lightweight concrete, fill with crushed stone, and then setting sand for the block steps in the staircase. Would it even be possible to do so? Perhaps, for example, if one casts on the lightweight concrete? OK, maybe not a great solution, risk perhaps of the lightweight concrete freezing and breaking, but it would solve two problems for us (getting rid of excess building material + avoiding having to bring in 30 cubic meters of crushed stone).
Solution 2: Gravel (16-32) at the bottom 40 cm, geotextile, existing fill material (mostly consists of stones of various sizes + sand & a little soil - so not suitable for anything to grow in, so it can't be used for anything where something needs to be planted), and finally about 30 cm of crushed stone of finer dimension and on top of this, the block steps. The question here is how to ensure that the existing fill material doesn't settle over time making the staircase uneven?? The staircase adjoins one side to the retaining wall and the other side to a slope.
Solution 3: Clearly the most expensive!! Buy 30 cubic meters of gravel or similar and fill up with and place the block steps on that.
Does anyone have any thoughts? Advice?
Yes, short spans, lots of reinforcement + buttresses + cast as T-support at the bottom, etc. Sure, we can advertise the lightweight concrete, but it would be easiest if we could just stack it up inside the retaining wall according to idea 1. What do you think??
Aerated concrete "kritsten" absorbs moisture and suffers from frost damage. Whether this then causes the masses to rise or collapse is open to speculation. Probably not the best fill if you want a stable ground level.
Yes, that's what we are speculating as well - probably not leaning towards it being worth the risk with the leichtbetong. But solution 2 then? How worried should one be about the existing masses settling? Our contractor doesn't seem worried about it.
I built a retaining wall that is 1.8m with shared counterforts with the pool, I didn't dare take a chance, so I went with 16-32 and I don't regret it, it became insanely stable.
I can calmly say that I sleep well at night.
In my case, it took 3 loads of 13 tons each to fill....
/Peter
I can calmly say that I sleep well at night.
In my case, it took 3 loads of 13 tons each to fill....
/Peter
Yes, that might be the only straightforward option. It's just sad to drive away with lots that might be useful... it's impossible to place elsewhere since it doesn't contain any soil directly. Maybe not daring to take a chance, but still wondering if it could be a solution.
Is there anyone who believes in solution 2? Or should we just go with solution 3, like Peter, plain and simple? Oh, what indecision.
Is there anyone who believes in solution 2? Or should we just go with solution 3, like Peter, plain and simple? Oh, what indecision.
I think #2 might work if you make an effort to compress the filling material while filling. But, I would fill with 0-32 and/or 8-16 next to the leca wall to drain away water and avoid frost heaving against the wall.