Bitumen-sand as fill under storage tanks
Bitumen-sand as fill under storage tanks
(OP)
Hello
I can see that bitumen-sand is a returning topic in this forum, therefore apologies for re-opening the subject.
Our national recommendations (Denmark) state that a concrete slab with a layer of bitumen-sand above it can be accepted as a secondary barrier for a steel-bottom tank.
But as far as I understand from my research on the internet, the bitumen-sand-layer isn't a impermeable barrier, and could might as well be substituted with sand-fill or equivalent?
My problem is that the recommendations dosn't mention pure sand-fill, and it dosn't mention reasons why it should be a bitumen-sand-layer. It refers only to EMMUA 183, which, as I see it, isn't dosn't explain it neither. And I do not want to deviate from the recommendations as long I don't understand the topic fully.
So can anybody point me in the direction of the source/reasons for the use of bitumen-sand under tanks, or maybe some litterature where pros and cons are explained?
I can see that one of the pros should be regarding corrosion of the steel-bottom, but in our case, the bottom is seperated from the fill by a layer of thermal-insulation.
Best regards,
Kasper
I can see that bitumen-sand is a returning topic in this forum, therefore apologies for re-opening the subject.
Our national recommendations (Denmark) state that a concrete slab with a layer of bitumen-sand above it can be accepted as a secondary barrier for a steel-bottom tank.
But as far as I understand from my research on the internet, the bitumen-sand-layer isn't a impermeable barrier, and could might as well be substituted with sand-fill or equivalent?
My problem is that the recommendations dosn't mention pure sand-fill, and it dosn't mention reasons why it should be a bitumen-sand-layer. It refers only to EMMUA 183, which, as I see it, isn't dosn't explain it neither. And I do not want to deviate from the recommendations as long I don't understand the topic fully.
So can anybody point me in the direction of the source/reasons for the use of bitumen-sand under tanks, or maybe some litterature where pros and cons are explained?
I can see that one of the pros should be regarding corrosion of the steel-bottom, but in our case, the bottom is seperated from the fill by a layer of thermal-insulation.
Best regards,
Kasper





RE: Bitumen-sand as fill under storage tanks
RE: Bitumen-sand as fill under storage tanks
http://www.eng-tips.com/viewthread.cfm?qid=359944
http://www.ast-forum.com/ast_forum_tree.asp?master...
http://www.ast-forum.com/ast_forum_tree.asp?master...
http://www.buildingmaterials.co.uk/bitumen-impregn...
MJCronin
Sr. Process Engineer
RE: Bitumen-sand as fill under storage tanks
Especially the first link at www.ast-forum.com was usefull.
Regarding thermal insulation, we are planning to use foamglas or equivalent, maybe substituted with brick type insulation where the plates are being welded.
We would like to avoid the bitumen-sand if possible.
Best regards,
RE: Bitumen-sand as fill under storage tanks