Reactions in Midas 2018

Creation date: 11/26/2018 5:10 PM    Updated: 11/27/2018 3:41 AM    impact factor permit truck
Question:

Hi,


I'm currently working on an assessment and need help with the following:


The reaction forces I'm getting when applying special type vehicles (user defined) is incorrect. I have introduced a vehicle with 7 Axles and 100 kN per wheel, therefore the maximum reactions in Fz should be equal to around 1400 kN. When checking the concurrent reactions and summing them up I'm getting more than double (2940 kN).


Can you please advise what is the matter with the reactions and how I could get the correct ones as this is clearly wrong.


Regards,


Answer:

Hello ,

The reason is the Impact Factor that you have applied. In MIDAS, this factor is added to the normal value of the loads, i.e. if the factor is 1.1, then the software multiplies the loads by 1 + 1.1 = 2.1. From there you can easily see why the total reaction is 2940kN. If you specify a value of 0, then you will obtain exactly 1400kN of total reaction.

I have checked the Online Manual and have notice that there is no information and this is not clear. Please accept our apologies for this, we will look to improve the manual to clarify this.

Kind regards,
Technical Support Team
MIDAS UK
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