{"id":32479,"date":"2019-01-07T14:12:15","date_gmt":"2019-01-07T14:12:15","guid":{"rendered":"\/forum\/forums\/topic\/increase-contact-force-reaction-czm-mode-ii\/"},"modified":"2019-01-07T14:12:15","modified_gmt":"2019-01-07T14:12:15","slug":"increase-contact-force-reaction-czm-mode-ii","status":"closed","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/increase-contact-force-reaction-czm-mode-ii\/","title":{"rendered":"Increase Contact force reaction – CZM mode II"},"content":{"rendered":"

Hi Ansys Community<\/p>\n

<\/p>\n

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. <\/p>\n

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<\/p>\n

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.  <\/p>\n

<\/p>\n

* Force obtained from the instron machine (Experimental force F = 20 KN<\/strong><\/em>)<\/p>\n

<\/p>\n

* Force from the model without CZM<\/strong><\/em> (default contact in ansys (Program Controlled) > F = 17-18 KN<\/strong><\/em>) – Close to experimental.<\/strong><\/em><\/p>\n

<\/p>\n

* Force from the model with CZM activated <\/strong><\/em>(Pure penalty – Augmented Lagrange)> F= 12 KN max<\/strong><\/em>) – Far From Experimental. (How to increase this value from 12 to be near 20 KN from experimental).<\/strong><\/em><\/p>\n

<\/p>\n

I tried the following<\/strong><\/em><\/p>\n

<\/p>\n

* increase the contact stiffness through commands in order to increase the reaction force but convergence issues occurs. <\/p>\n

<\/p>\n

* Switching between contact algorithms (Pure penalty – Augmented Lagrange)<\/p>\n

<\/p>\n

* Normal stiffness as program controlled, absolute value and a Factor with stiffness update to (each iteration – never).<\/p>\n

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Thanks in Advance<\/p>\n","protected":false},"template":"","class_list":["post-32479","topic","type-topic","status-closed","hentry"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t