Contact in Explicit Solver

Hi there, thanks for kindly supporting the use and development of the Calculix. I have been re-directed here from github.

I have recently assembled an model with the beam-to-solid contact. The explicit solver seems produce unreasonable results that the energy raised to the INF level at some stage.

The load case is simple that

  1. the cellular body (consisting many beam elements) sits on the top of the bottom supporting plate
  2. the top loading plate moved downward to compress the cellular body. The top plate can only move in the vertical direction, and were constraint by the imposed boundary conditions.
  3. the cellular body has no other movement constraint, besides the contacts to the top and bottom plates.

I have attached zip files here, both the INP files and the results outputs. I do understand the the “beam” is not actual beam element, so the top and bottom plates were offset a bit (0.25mm) in order to accommodate the reproduced solids from the beams. The solver versions are 2.16 and 2.15.

I’d like to also confirm one thing, whether the "*tie " keywords were implemented for the explicit solver. I found it was not implemented.

You may see the attached models and results at:

Thank you!