Hi,
Would any one be able to give me instruction/ standard test method for Micro Deval test applied to railway ballast in European countries?
The standard of En1097, does not purport to address all size of aggregates; Also it just covers 10 to 14 millimeter particles. So that, how can apply that standard test method (En1097) to railway ballast?
All the best
Leila
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Leila Azizi
Hi,
The test method you refer to is in an annex of EN13450 (product standard for rail ballast).
The main differneces to the standard Micro Deval are:
Sample size 10kg not 500g
No steel charge is used.
Revolutions are 14000 not 12000 and the drum is much bigger.
Hope this helps!
Martin
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Martin Ashfield
Martin hi,
I was wondering if you had any ideas on a problem i ve encountered with some rail ballast. Initial specification has been changed to a specification that is harder to meet. The new spec requires a Los Angeles value of below 20 and a Micro Deval value of below 7. My latest ballast test results produced results of 24 LA and 8.5 for MD.
My grading also failed in that it contained to high a percentage I could have accomodated a lot more in these size fractions. Also the particle length requirement failed hugely in that the requirement was less than 4, my result was 21! But the flakiness requirement didn't fail with a result of 3 and a requirement of under 35. Have you guys any suggestions as to how I can get this ballast to meet the specification? Obviously the grading can be changed would this make up the difference on its own? Would this make a difference at all?
Any help would be greatly appreciated
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trevor
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