making shed base question on geotextile membrane

[happyhero]

Hi I am making a concrete shed base and I was told to put a Geotextile membrane down on the soil as it will stop the hardcore/mot1 migrating into the subsoil, but if I put that down first and then start smashing my leftover hardcore on it and adding some mot1 and then using a wacker plate on the whole lot wont it pierce the membrane and ruin it?

I cannot understand how you put down a membrane and then put a load of rough sharp stuff on top and then get rough with it and not damage the membrane. Am I missing something?

Appreciate any advice please.

 

[jks7492]

Hardcore and type 1 directly onto firm ground, sand blinding, DPM and then concrete.
Sand blinding stops the membrane being pierced by sharp stones.

 

[happyhero]

So I got this about using a geotextile membrane under mot1 layer from paving expert.com and showed my builder friend who I can't now get hold of and he said I should do this.....

to summarise, its primary purpose is as a separation membrane , preventing the sub-base or bedding material mixing with the underlying layers, which can result in excess settlement or pumping of a particularly weak sub-grade, which, in turn, can cause settlement and rutting.

Makes me think it's obvious I should use it, are you suggesting I don't? If so can you explain why I don't need to worry about the bit mentioned above please, I'm just trying to understand it all?

 

[Alastairreid]

You don't use membrane under type 1 for a concrete base..maybe a garden path or similar.

 

[noseall]

So I got this about using a geotextile membrane under mot1 layer from paving expert.com and showed my builder friend who I can't now get hold of and he said I should do this.....

to summarise, its primary purpose is as a separation membrane , preventing the sub-base or bedding material mixing with the underlying layers, which can result in excess settlement or pumping of a particularly weak sub-grade, which, in turn, can cause settlement and rutting.

Makes me think it's obvious I should use it, are you suggesting I don't? If so can you explain why I don't need to worry about the bit mentioned above please, I'm just trying to understand it all?

Geo-tex membranes are for heavy traffic or commercial use and in particular - for poor ground with soft pockets and spongy areas. Your shed base will be fine without it. In fact most shed bases will sit ok on well bedded slabs as long as you dig off the vegetative matter beneath.

Your builder friend is just flexing his 'how to influence a DIY'er' muscles.

 

[^woody^]

It's probably good that the builder friend has gone incognito. You are safe from other gems of advice.