Pre-tensioned Beam

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in the example “csm3_casting_bed_method.dat” of CSM, it is stated that AQB uses Ecm @ 28days to compute stresses, therefore we need to deduct the additional losses from the initial stress input for the tendons (please refer to the example). My question is if we deduct this additional losses in advance, then calculation of shortening losses will be done, by considering this effective stress (initial stress - manually deducted loss), which then underestimates the losses further !, as we have input lesser initial stress. So how correct is this method ?

I think when you just modify Ecm you can find it out by yourself.

Hi
i’m elaborating my question further, to explain the issue.
If the initial stress of S1=100 MPA was given as input, then AQB will calculate loss considering Ecm@28days, let say this loss as “L1” MPa. However, the actual loss should be “L2” MPa, considering Ecm at time t (t<28days) (L2>L1).
Example suggest that the difference of L2-L1, must be substracted in advance from the initial input stress of 100 MPa, (S2=100-(L2-L1)). if I do so, the calculation will now be based on S2, which lesser then S1, hence my results will be further underestimated!

Detail answer will be appreciated. Thankyou.