Topic: apply cyclic load on reinforced concrete beam

Hi,

I build up a reinforced concrete model which similar to the example model in Atena Science tutorial. I would like to know how to apply cyclic load on the beam, the beam is under the cyclic load which is ranged from 21kN to 74 kN at frequencies of 3 Hz.

could you give me some hint about it ?

Thanks

Re: apply cyclic load on reinforced concrete beam

Dear ab1234, please first see ATENA Troubleshooting, 2.2.26 How can I model cyclic or fatigue loading? for basic related information (then, contact us to clear the remaining questions/unclarities).
Regards.

Re: apply cyclic load on reinforced concrete beam

Hi,

Thanks for your reply. I have viewed the tutorials and followed them step by step, but the analysis was interrupted due to some mistakes that I cannot identify.
Last time I build a plain concrete model under static load and the result (loading vs deflection graph) was pretty good, this time I tried to build a steel fibre reinforced concrete under cyclic loading ( the load range was provided by my teacher), so based on my old model, I did some modification as listed below
1) change the 'Solid Concrete' properties into 'Cementitious 2', mateiral prototype 'CC3DNonLinCementitious2Fatigue' ( i am using atena science)
2) add a monitor for EXTERNAL FORCES at the loading point
3) add six internal data ( this process I am not sure if the interval multiplier and load steps are correct or not)
4) click on 'Write Fatigue Applied Cycles Monitor' in Problem data-> global options

Please let me know if there is any mistake about these four steps and anything i need to improve. since i have prescribed force level in each cycle ( 0 kN->22kN->40 kN ->11kN ->40 kN ->11 kN), I have no idea about how to apply these loads in the 'Interval Data'. If possible, could you please give me some advice?

with best regards

Re: apply cyclic load on reinforced concrete beam

Dear ab1234,
1. I recommend to also see the Fatigue example included in ATENA installation (%Public%\Documents\ATENA Examples\Science\GiD\Tutorial.Static3D\DirectTensionFatigue.gid).

2. Please keep in mind loads are incremental in ATENA (see also Troubleshooting, 2.2.15 How to model a load combination, e.g., a constant vertical force during horizontal displacement applied until failure?).

3. Please see also ATENA-GiD User's, 5.3.1.3 CC3DNonLinCementitious2Fatigue and 5.4.1 Fatigue.

4. For additional / background information, you can see ATENA Theory, 2.2.10 Fatigue.

5. If the problems persists or new questions arise, you can send us your model etc. following Troubleshooting, 2.1.1.

Regards.

Re: apply cyclic load on reinforced concrete beam

Hi,

Thanks for the advice. but my deflection vs number of cycles graph is a strainght line which is impossible. could you help me to check the model.

with best regards

Re: apply cyclic load on reinforced concrete beam

Yes - please send us the model etc. (Troubleshooting, 2.1.1).