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Would it be possible to model concrete member reinforced with FRPs bars (i.e. GFRP, CFRP OR BFRP)? and also guide could we import "section model" or " FRP model" file(matlab ) TO ETABS for analysis? i have read somewhere on CSI Web that the only option is its equivalent modeling in such way that extra steel bars used in beam to model the glass fiber as a replacemt of FRP to incresea the beam strength? is it possible to do so. S

yes sir, i know about ACI 1R 440 for designing FRP reinforced flexural members, According to ACI frp is still not approved for compression member due to its anisotropic behaviour. Canadian Code for FRP i think provide complete design guidlins.

1. Pattern loading (continuous beam assumed as simply supported) is used for live load only. 2. It is necessary in a real building to account for variability in loading conditions. 3. If you are trying to do just a simple beam, make pattern live load = 0

ETABS does this in a way by a pattern live load factor. Have go through its manual on pattern live load factor.

ETABS does give correct values of reo (it does take into account the lower/upper limits of reo for a particular code). Totally agree and recommend first 2 points. However, I do not think, ETABS in 2019 has bugs for such simple things. Yes, it does have few bugs like any other package but for sure not related to these basic things. Please check what code says when you provide As = 1.33 x Asreq ??? And why ETABS giving less moment and reinforcement than what you getting manually is totally a different question and depends if you are modelling it right or if you are manually calculating it right.

Also, take care that the torsional shear reinforcement = area of only outermost 1 closed stirrup. In other words, make sure the outermost continuous big stirrup (have 4 legs all around) is sufficient to carry all torsional shear. You can't distribute in among internal stirrups. However, you can provide multiple stirrups (verticals legs only effective) for flexural shear. Also, if one stirrup (flexural or torsion) is not enough, provide 2 bundled stirrups side by side along beam length or reduce spacing.

Please first refer to the ACI documents for Design of Concrete Structures using FRP BARS. Simply using the software does not guarantee the correctness of structural design. I see you are in Nanjing University in China. Are you doing graduate work there or working in a design office ?

The information provided by Mjnasar is correct: ACI 318 says that the torsion reinforcement is additive to the required flexural reinforcement in your case, u can distribute the steel in 2 top corner bars + 1 side bar + 2 bottom corner bars ( Addl to top & bottom Flexural reinforcement )

Have a look to field practicing manual prepared after the 2005 Earthquake.

Dear @Saiful Islam Zaber Please see this link https://wiki.csiamerica.com/display/kb/Pattern+live-load+factor and the picture attached. Hope this will suffice your query.