Concrete Blocks

[NigelKennedy]

Thinking of using concrete blocks to build a raised vegetable garden but reading these blocks are the new asbestos due to the fly ash used in the cement. Any clever people out there know if fly ash is used in thai cement.

[Bill97]

The usual Thai block is not strong and would easily break up. Fly ash????? Good luck with that. Thailand is a large asbestos user but nobody seems willing to acknowledge using it.

[colinneil]

In your post the blocks are 6 inch blocks, not the usual 2 and a half inch you get here.

Thai blocks would not be strong enough for raised beds.

Why not do the same as me, concrete rings.

[Bill97]

You can get strong 6" blocks here, past MaeJoe left side before traffic light about 100 m??

[eyecatcher]

Dont panic about the blocks here. What you are talking about is p.f.a blocks; clinker blocks in my language. Its not fly ash I think you have misheard....it means pulverised fuel ash and the blocks were made from the derivitives of the old power station slag mixed with concrete. They have excellent thermal properties, hence their use in housebuilding in the West not that your plants give a monkeys about that.

Personally the general hollow blocks 50/60/70mm thick are perfect for your needs here and at only (from 4.5bt-7bt) minimal cost.

but also a neat idea are the concrete rings near the gentleman in the photo, at only 100bt each i find them perfect for temporary homes for trees. i have a bout a dozen that i transplanted a year ago awaiting a new home, and all are doing well.

And for all you who say the blocks here are not strong......exactly the same as a concrete column.......very weak in tension but very strong in compression kao jai?

[pgrahmm]

The usual Thai block is not strong and would easily break up. Fly ash????? Good luck with that. Thailand is a large asbestos user but nobody seems willing to acknowledge using it.

So what block is best used for construction? I have a friend in PI that formulated their own building block composition - feasable here????....

If/when I decide to build I'd planned on double walked with blocks....

Edited February 16, 2016 by pgrahmm

[NigelKennedy]

My initial question was regarding fly ash in cement. I am not worried about the strength of blocks. A bit more research and I have found Fly Ash is used a cheap substitute for cement and in Thailand cement can be up to 60% fly ash. The power plant in Lampang was producing 9000 tonnes daily in 2002.

So it seems growing any kind of vegetables close to concrete is not safe at all. The article in www.preventdisease.com is very informative. So I will not be using blocks or concrete rings. Thinking to use clay bricks.

[NigelKennedy]

Toxic Fly Ash

[eyecatcher]

The usual Thai block is not strong and would easily break up. Fly ash????? Good luck with that. Thailand is a large asbestos user but nobody seems willing to acknowledge using it.

So what block is best used for construction? I have a friend in PI that formulated their own building block composition - feasable here????....

If/when I decide to build I'd planned on double walked with blocks....

Your best choice would be aac blocks (such as QCon/dura). the cheap blocks they use here retain the heat so double skin is imperative. use bricks..........well you know what they built kilns from!!.....and why? because they retain heat longer than the blocks.

[Bill97]

Eyecatcher

Do you know the blocks I have mentioned made in the factory mentioned? No offense but they are not well known here as they are in other countries.

[eyecatcher]

Eyecatcher

Do you know the blocks I have mentioned made in the factory mentioned? No offense but they are not well known here as they are in other countries.

I dont know specifically which block you are referring but its quite easy to buy solid concrete blocks at 4,6,8 inch wide.

And of course the aac blocks come in those sizes also but shouldnt be used in the ground.

[Thorgal]

Fly ash is also used in AAC blocks.

OP can sonsider (double row) interlocking clay bricks. Available in CM.

Or concrete poured walls with pure cement/sand/stone/water mixture.

Edited February 17, 2016 by Thorgal

[bangmai]

It had occurred to me that the PVC hydroponic gardens might also be deteriorating into the plant. At least some of the plastic pipes are extremely sensitive to the sun.

Remember the PBS series: Square Foot Gardner? https://en.wikipedia.org/wiki/Square_foot_gardening Never once saw them use cinder blocks...

Edited February 17, 2016 by bangmai

[luther]

I would recommend the Lego type bricks Thorgal mentions. I built the base of a pizza oven using them. Build the walls. place rebar in the holes, pounding it into the ground. Mix a watery concrete slip and poor it in. It moves from brick to brick and fills up the wall.