# \*Tie and surfaces? **URL:** \ **Category:** Uncategorized\ **Created:** [December 6, 2021, 10:27am UTC](https://calculix.discourse.group/t/tie-and-surfaces/887 "2021-12-06T10:27:04Z")\ **Posts on this page:** 1\ **Showing post:** 3
**Author:** ![Calc\_em](https://avatars.discourse-cdn.com/v4/letter/c/43a26b/32.png) [@Calc\_em](https://calculix.discourse.group/u/Calc_em)\ **Post date:** [December 6, 2021, 12:03pm UTC](https://calculix.discourse.group/t/tie-and-surfaces/887/3 "2021-12-06T12:03:10Z")
Check these threads: > [@Is contact of beam and shell allowed in CCX?](https://calculix.discourse.group/t/is-contact-of-beam-and-shell-allowed-in-ccx/270): > > hi, i’m modeling contact analysis of beam and shell faces, try a simple model but did not succeed. anyone has experiences, are the solver CCX allowed this analysis type? or something i miss at input decks. bellows are input files, thank you. \*\* Objective : Beam to Shell Contact \*NODE 1,0,0,0 2,100,0,0 3,100,100,0 4,0,100,0 5,50,25,10 6,125,50,10 \*ELEMENT,TYPE=S4 1,1,2,3,4 \*ELEMENT,TYPE=B31 2,5,6 \*ELSET,ELSET=eplate 1 \*ELSET,ELSET=ebeam 2 \*SURFACE,NAME=splate 1,SPOS \*SU… > [@Case with 2 connected plates of different materials not working](https://calculix.discourse.group/t/case-with-2-connected-plates-of-different-materials-not-working/662): > > Dear all, I’m in trouble with an apparently super-silly case of two connected consecutive plates (of different material) subjected just to their weight and with an extremity which is fixed. The plates are modeled with shell elements. As you can see from the attached figures, the nodes at the plate-to-plate interface are conformal. The problem is that CCX leads to a solution that seems not to consider as attached the two plates (as you see from the super-high displacements of one of the two plat… Tie constraint is really versatile and can be used for beam-solid, beam-shell or solid-shell connections as well. Here’s an example: ![shell 1](https://global.discourse-cdn.com/free1/uploads/calculix/original/1X/950b98eb21404cb98b4b9c74c67e559f5421727f.png) ![shell 2](https://global.discourse-cdn.com/free1/uploads/calculix/original/1X/8b89b8c2c2a4208ea0b413a1d54deac99a731de3.png) ![shell 3](https://global.discourse-cdn.com/free1/uploads/calculix/original/1X/c211afcf949d25580cce487b972a5a435bab182a.png) As you can see, the deflection is well represented but the stresses become distorted. The same happens in Abaqus and that’s why Abaqus offers shell-to-solid coupling functionality which eliminates this issue. Unfortunately, CalculiX doesn’t have such a constraint implemented. --- _[View the full topic](https://calculix.discourse.group/t/tie-and-surfaces/887)._