Timber Shear Wall Modelling

General Questions
1

Hi everyone! I hope you are doing well. As I am trying to model a timber shear wall with studs and sheathing, I am facing a challenge to rigidly tie the sheathing to the other way. the thickness of my sheathing is 13 mm, and I have drawn the sheathing plane in a way that the inner face of it exactly touches the outer face of my studs. I would deeply appreciate any solutions or help pertaining to this matter. I can also share my modelled file for debugging purposes. I receive this warning when I check my model for multiple nodes: 07/16/2025 17:10:38

######## Starting run step number: 1 Increment number: 1 ########

Running command: C:\Users\farza\Desktop\PrePoMax\PrePoMax v2.3.5 dev\Solver\ccx_dynamic.exe Analysis-1

CalculiX Version 2.22, Copyright(C) 1998-2024 Guido Dhondt
CalculiX comes with ABSOLUTELY NO WARRANTY. This is free
software, and you are welcome to redistribute it under
certain conditions, see gpl.htm

You are using an executable made on Sun Aug 4 19:44:24 2024

The numbers below are estimated upper bounds

number of:

nodes: 29746
elements: 673
one-dimensional elements: 0
two-dimensional elements: 442
integration points per element: 8
degrees of freedom per node: 3
layers per element: 1

distributed facial loads: 0
distributed volumetric loads: 0
concentrated loads: 0
single point constraints: 38736
multiple point constraints: 53041
terms in all multiple point constraints: 339457
tie constraints: 1
dependent nodes tied by cyclic constraints: 0
dependent nodes in pre-tension constraints: 0

sets: 24
terms in all sets: 4016

materials: 1
constants per material and temperature: 2
temperature points per material: 1
plastic data points per material: 0

orientations: 442
amplitudes: 6
data points in all amplitudes: 6
print requests: 0
transformations: 0
property cards: 0

*WARNING reading *TIE: parameter not recognized:
ADJUST
*WARNING reading *TIE. Card image:
*TIE,NAME=STUDS_SHEATH_TIE,POSITIONTOLERANCE=8.0,ADJUST

STEP 1

*INFO reading *STEP: nonlinear geometric
effects are turned on

*WARNING reading *STATIC: a nonlinear analysis is requested
but no time increment nor step is specified
the defaults (1,1) are used

*WARNING: no analysis option was chosen
No analysis was selected

Nonlinear geometric effects are taken into account

*WARNING in gentiedmpc: no tied MPC
generated for node 1459
no opposite master face
found; in-face tolerance: 0.72265692075076482
*WARNING in gentiedmpc: no tied MPC
generated for node 1462
no opposite master face
found; in-face tolerance: 0.72265692075076482
*WARNING in gentiedmpc: no tied MPC
generated for node 1465
no opposite master face
found; in-face tolerance: 0.72265692075076482
*WARNING in gentiedmpc: no tied MPC
generated for node 1468
no opposite master face
found; in-face tolerance: 0.72265692075076482

2

Do you only get these warnings or are there also some errors or the analysis doesn’t run / provides incorrect results ?

Are you using shell elements ? Then you should position the parts (or offset the shell section) in such a way that when the shells are expanded to solids, there are no avoidable overlaps.

3

Timber_Shear_Wall_Debugged+Upto_SheathingToStuds.pmx (209.8 KB)
Hello Mr. Michalski,

I hope you are doing well. I hereby attached my model for your kind attention. I would deeply appreciate it if you could double check it. As you mentioned, before I even write this topic, I have already offset the mid face of the sheathing about 6.5 mm; however, I still face some errors.

4

If you run the Check Model procedure, you will see some interference:

interf
interf1026×604 27.5 KB

Setting the shell section offset to -0.5 will let you avoid it:

offset
offset336×325 4.97 KB

no interf
no interf1031×613 26.8 KB

Also, I see that you defined tie constraints via Keyword Editor. It’s not necessary, tie constraints are available in GUI:

tie
tie710×542 21.5 KB

And finally, run a frequency analysis to confirm that tie constraints is working properly.

1 Like