Define materials

[simon1000]

I have a RC model which is designed by ETABS. The material properties are as follows:

Concrete:
f'c=25000 KN/m2
unconfined strain= 0.002219
ultimate unconfined strain= 0.005

Steel:
fy=400000 KN/m2
fu=600000
expected yield strength=0
expected tensile strength=0
ultimate strain=0.09
hardening strain=0.01

Could you please help me to define these material in SeismoStruct correctly? I only should be define C25/30 and S400? Are the default values for these selections consider my materials?

[huffte]

I would suggest creating new materials in the Materials tab.

Try the "Mander" concrete model with a user-input confinement factor equal to 1.0 for the concrete (I am assuming you do not wish to model confinement enhancements to stress-strain properties, given your description).

Try the "Bilinear" steel model. You can set the desired parameters in the material definition screen. Other models may suit you more as you investigate their various capabilities (Menegotto-Pinto, Dodd-Restrepo, Monti-Nuti, . . .)

Best of luck.

[simon1000]

Thank you for your answer. I have another question. I know that in the material tab and for steel material, ''mean strength value'' is fy (yield stress), but, what is ''lower bond strength'' and how could be calculated? Can I use the fy value for it again?

[huffte]

I confess that I cannot find a steel material in SeismoStruct which requires the input of "lower bond stress". Which material are you using?

[z.gronti]

Dear simon1000,

The lower-bound strength value is required for the code-based checks of existing materials and is equal to the mean strength value minus one standard deviation.

[z.gronti]

Dear Tim Huff,

The mean value as well as the mean strength value minus one standard deviation are parameters required for the code-based checks of existing materials, which have been introduced in SeismoStruct 2016. For new materials the characteristic strength value and the mean strength value should be assigned.

[huffte]

I learned something today. So it is a good day. Thanks very much, Zoi Gronti.