Ultimate shear resistance results interchanging two different values for Vc/Vco

[Anonymous]

Hi there,

I'm carrying out an grillage analysis of a prestressed concrete beam bridge with infill concrete between/above the webs (see pic one).

Vco =  130.014, yet in the next section as the cracking moment is greater than applied, Vc=Vco but then Vc is stated as =133.937 (see pic two)

I've attached the results file, not sure what is going on so would appreciate any help you can offer.

Thanks,

Charlie

[karoly_tarcsi]

Hi Charlie,

Can you zip and attach your model for inspection?

Thanks,

Karoly Tarcsi

Software Development

[Anonymous]

Here you go

[karoly_tarcsi · Accepted solution]

Hi Charlie,

In Clause 6.3.4.2 shear capacity of "PC-beam only" is calculated as 130.009kN. 

However capacity of composite section in Clause 7.4.2.2 is found to be 133.937kN after the evaluation of shear strength of the infill in Clause 5.3.3, resulting Vc = 133.937kN in Clause 6.3.4.2.

Please find attached a marked-up shear design report of your Inner beam SB1.

Regards,

Karoly Tarcsi

Software Development