Hello,
I work with ATENA 3D as part of my master thesis and try to describe my problem. Basically, I simulate a beam from an experiment and then do a parameter study. The beam is a prestressed T-beam with a total length of 12 m and 2 symmetrical fields with a length of 6 m each. The beam is reinforced differently in both fields and is uniformly loaded in both fields by a single load. In the experiment, the weaker-reinforced field (Field 1) was strengthened shortly before failure with the help of 5 traverses above and below the beam which are connected with threaded rods, so Field 1 could not fail due to shear force. Subsequently, the beam was further loaded in both fields until the failure of the more reinforced field (Field 2). In this way 2 experiments could be carried out on one beam.

My question: Is it possible to simulate the modification of Field 1 as in the experiment? The Field 1 must continue to be able to twist, as the load attacks eccentrically. However, the Field 1 must not fail due to shear force under further load.
I have already considered that the entire beam is modeled once only with the reinforcement as in field 1 and once with the reinforcement as in Field 2, but I'm not sure if the overall load behavior is not different. I would like to picture the beam as realistically as possible.

Many thanks for the help.

Regards.