Hello All,
I am currently modeling a retaining system include vertically stacked concrete units within different construction phases. I have initially defined the geometry of all zones and interfaces. In the construction phase (based on my understanding), I have initially set material properties to ‘null’ for all construction phases and solved the model for initial condition. Then started activating stages by assigning corresponding materials for each construction stage/limit and solved each stage individually.
I have realized that during the first construction stage, ‘is in contact’ is ‘on’ for all activated interfaces (velocities are very low and in order of 1e-10 and displacements are reasonable). Moving forward from the second stage construction, ‘is in contact’ is ‘off’ for many of defined interfaces. I see high velocity values and unrealistic interface displacements (at interfaces with no contact). It appears that this happens due to gridpoint mismatch due to displacements from previously solved construction stages. Indeed, after solving the first stage construction, all gridpoints experience displacements which can be numerically beyond zone interface contact tolearnce.
I have somehow confirmed this evaluation by activating the entire retaining system in one construction stage and in this case, all interfaces are in contact and I do not see unrealistic displacement values.
What I have experienced in this model should be a very common challenge for problems with different construction stages. Unfortunately I couldn’t have found a clear-straight forward solution and I’d appreciate it if you share your experience on how to overcome this challenge.
Regards,
Ali