## General Mechanical

• Fraol
Subscriber

Hi. i am a structural engineeing student trying to validate results of an experimental result numerically.  The specimens are RC columns fixed on the bottom under uniaxial loading. The load was applied concentrically with a displacement control rate of 0.5mm/min .The loading sequence included five loading cycles, each of which was repeated once, with increments of one fifthof the expected capacity.

what is the best way to model to replicate the above loading conditions to the column.
N.B. since i am a beginner to FEM be as descriptive as you possibly can.
Edited: the model i have modeled can be found here

• peteroznewman
Subscriber

What data was taken from the experiment?  How many specimens were tested?

What happened at the end of a loading cycle, was the column unloaded, or did the displacement pause at the end of one cycle and continue into the next cycle?

When you say the last load cycle was to reach the expected capacity, do you mean the ultimate capacity when the peak force was measured?

During which load cycle were cracks in the concrete observed?

• Fraol
Subscriber

peteroznewman Thank you for replying. I will try to answer your questions one by one as i undersand them.

1. What data was taken from the experiment?  How many specimens were tested?:  In the experiment there were 12 full scale column specimens tested for the performance under axial load. the data taken was ultimate load, deformation and strain using LVDT sensors.

2.What happened at the end of a loading cycle, was the column unloaded, or did the displacement pause at the end of one cycle and continue into the next cycle?: althoughn not ver descriptive, in the article* since it says 'after one loading cycle the other was repeated with added one fifth capacity' i think the column was unloaded and then reloaded with the increased load.

3.What happened at the end of the fifth loading cycle?: the specimens were observed until they reached the failure criteria. which is cracking.

4.by 'expected capacity'....it means the axial concrete compressive strength of the specimen. and the peak force is the force that causes around concrete axial stress of about 75-80% of the average comperssive strength.

5.During which load cycle were cracks in the concrete observed?: it was different for every specimen, but its around the 4th and 5th

* the article was a published experimental design. i will attach the three pages necessary to answer the above question. it is not very descriptive for me.
NB. i have attached one of the columns i have modeled using ansys.