SPCFORС and RCFORC

[Николай Водяхин]

Hello! I've calculated a bolted connection and am comparing the load-deformation graph from FEA with the experimental data. I need to determine the load at different stages and the failure load. ls dyna has rcfor and spcforc. Which map should I use? The values ​​in rcfor and spcforc are different.

[James Kennedy]

Dear Nikolay,

 

Two options were proposed for modeling of bolted joints, either with beam elements or with

solid hexahedra elements to address pre-load/pre-stress, bearing stresses, clamping forces, part

interface friction, and failure modeling:

 

Narkhede, S., Lokhande, N., Gangani, G., and Gadekar, G., "Bolted Joint Representations in

LS-DYNA to Model Bolt Pre-Stress and Bolt Failure Characteristics in Crash Simulations",

11th International LS-DYNA Users Conference, Dearborn, Michigan, June, 2010.

 

http://www.dynalook.com/international-conf-2010/Simulation-4-2.pdf

 

Sincerely,

James M. Kennedy

KBS2 Inc.

December 8, 2025

--
You received this message because you are subscribed to the Google Groups "LS-DYNA2" group.
To unsubscribe from this group and stop receiving emails from it, send an email to ls-dyna2+u...@googlegroups.com.
To view this discussion visit https://groups.google.com/d/msgid/ls-dyna2/0d12dee0-02df-484b-8dc2-19d14c9007b1n%40googlegroups.com.

[Николай Водяхин]

I modeler bolt connection solid hexahedra elements

понедельник, 8 декабря 2025 г. в 21:04:56 UTC+3, jmk:

[James Kennedy]

Dear Nikolay,

 

A single shear joint subjected to shear loading and preload is compared for a 3D solid element

model and a 1D beam element model.

 

"Test Case Documentation and Testing Results: Test Case ID AWG-CI-2: Joints_ Fasteners

Shear Loading", LSTC-QA-LS-DYNA-AWG-CI-2-5, Livermore Software Technology

Corporation, Livermore, California, August, 2019.

 

https://awg.lstc.com/tiki-index.php?page=AWG+CI+Test+Example+2

(for documentation please see Test Case 2, Documentation and Results for LS-DYNA R11.1

Revision 139325 at the bottom of the page)

 

This is an example for a pre-stressed bolt joint. The bolt is modeled with solid elements (part 3).

It connects part 1 and 2. The screw is being pre-stressed by *INITIAL_ STRESS_SECTION.

Therefore a cross-section has to be defined. A second cross-section has been defined to control

the force.

http://www.lsdyna.eu/index.php?id=4019

 

This example may be more available:

https://lsdyna.ansys.com/bolt-pre-tensioning-example/

To view this discussion visit https://groups.google.com/d/msgid/ls-dyna2/94126e33-6a6d-4883-99e8-d32b206df435n%40googlegroups.com.