Monti Nuti steel model - buckling

[s.carbonari]

Dear all,

I'm using the monti-nuti model implemented in SeismoStruct to reproduce the experimental behaviour of a r.c. element. I have noticed that, with respect to version 5, version 7 of the program does not allow to input geometric parameters necessary to compute the rebar slenderness (transverse reinforcement spacing and longitudinal rebar diameter). From the manual, I deduced that default parameters are 0.1 m for spacing and 0.02 for rebar diameter (i.e. slenderness in 5). How does the model implemented in version 7 accounts for the buckling, which characterises the steel beahviour for greater slendernesses? Furthermore, parameter a2 defined in the paper by Monti & Nuti is 10^-4 while the default value reported in the material form is 0.15. What is the difference between these two parameters?

Does anyone has the answers to my doubts?
Thanks.

[seismosoft]

From version 7 onwards the user explicitly defines the longitudinal and transverse reinforcement in the sections module. Hence, the program automatically considers the transverse reinforcement spacing and longitudinal rebar diameter without further intervention by the users. Regarding the A2 parameter you can check the differences introduced in the hysteric rules of the model in sample plot in the Materials module.

Seismosoft Support

[s.carbonari]

Thanks.