Topic: Switch from unbonded to bonded reinforcements
I would like to simulate (in ATENA 3D Engineering) the construction phases of a prestressed concrete element, by reproducing the following steps:
Step 1) I define a concrete macroelement;
Step 2) I define some reinforcement bars (called "primary reinforcements") and I apply to these elements a pre-stressing load, in this step the bars are unbonded so I would like to simulate this behaviour;
Step 3) The reinforcements become bonded, but i don't know how i can reproduce the change of behaviour from unbonded to bonded (i've tried to define a bond material with very low properties for the unbonded phase and to switch to a perfect bond for the second phase, but it seems that the software doesn't allow to change the bond law once it is defined for the previous construction phase);
Step 4) I define addictional bars (called "secondary reinforcements") and I try to repeat the same steps made for the primary reinforcements.
I've made several attempts to reproduce this behaviour but i still can't reproduce the switch from unbonded reinforcements to bonded. How can I do to solve this issue?
In addition, I would like to know if, in a construction phase, is it possible to remove elements (added previously) or if is it possible (always in a construction phase) to change the type of an element e.g. from external cable to reinforcement bar. I've tried to do both but somthing seems to don't work.
Thank you in advance for your help.