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UNCF < 1 is not allowed
24-06-2019, 11:27 AM,
#1
UNCF < 1 is not allowed
Affected version: Ple4Win version 4.6.0

According to the NEN the uncertainty factor is a coëfficiënt, which can be used as value / UNCF or value * UNCF.
I have a situation where a pipeline is driftng up, so I want to use an uncrtainty factor 0.9 for UNCF in the SOILNB table.

   
   

It is not allowed to use that, so I have to use the LOADF less then 1.
As a workaround I put UNCF value from 1.1 to 1 and the LOADF from 1 to 0.9.
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25-06-2019, 10:16 AM,
#2
RE: UNCF < 1 is not allowed
Actually, this is 'as designed' and we do not have plans to change it.
The reason is that the UNCF factors are uncertainty factors, not load factors. For our kind of calculations, uncertainty always increases the load (Ple4Win always uses value * UNCF). If you are uncertain about a value it can never become more accurate than the value you entered.

In your case, you want to "misuse" Wink the UNCF column as a load factor column. We advise against this approach. As you said yourself, using the LOADF column is an alternative and in this case it the correct way of doing it.

By the way, in "real life" we also sometimes misuse the UNCF column in pipeline projects we calculate here (not in SOILNB or TOPLOAD, where LOADF-columns are available, but e.g. in settlement tables). Our usual approach then is to decrease the load by a factor of 10 and initially use an uncertainty factor of 10. If you decrease the uncertainty factor to 9 in a different run, you effectively get you 0,9 load factor Wink

In theory, we could also add a LOADF-column to other tables, but these situations occur very rarely, so adding these columns is probably more confusing than helpful.
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25-06-2019, 11:42 AM,
#3
RE: UNCF < 1 is not allowed
Okay.
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