Increase Contact force reaction - CZM mode II
Hi Ansys Community
Am studying the debonding between concrete and different materials, the two materials are bonded through adhesive. I did the modeling in workbench static structural. I want to verify the experimental test results through FEM. I am struggling with the contact force reaction validation (inserted a force reaction probe). A displacement controlled load is applied as a function of time (max displacement about 0.8 mm). Of course a CZM material is specified in engineering data with mode II parameters derived from experimental strain gauge readings through some equilibrium equations from literature.
I tried different concrete/micro-plane models CONC/MPLA with SOLID65/CPT215/SOLID185 elements, however the debonding takes place early (at about 0.59 mm displacement) with low contact force reaction.
* Force obtained from the instron machine (Experimental force F = 20 KN)
* Force from the model without CZM (default contact in ansys (Program Controlled) > F = 17-18 KN) - Close to experimental.
* Force from the model with CZM activated (Pure penalty - Augmented Lagrange)> F= 12 KN max) - Far From Experimental. (How to increase this value from 12 to be near 20 KN from experimental).
I tried the following
* increase the contact stiffness through commands in order to increase the reaction force but convergence issues occurs.
* Switching between contact algorithms (Pure penalty - Augmented Lagrange)
* Normal stiffness as program controlled, absolute value and a Factor with stiffness update to (each iteration - never).
Thanks in Advance