Failure to run analysis

Post Reply
shiRo
Posts: 20
Joined: Thu Oct 12, 2023 8:55 am

Failure to run analysis

Post by shiRo » Mon Nov 18, 2024 2:13 pm

Dear STKO team,
I am trying to build a complete bridge, adding bearings and beams on the basis of the original piers. I refer to the modeling methods that have been used in the forum, using zero-length elements to simulate bearings and using elastic elements to simulate beams, but they cannot run successfully. From the given error report, it may be that there is an error in the zero-length . Can you help me check the model ?
best wishes!
Attachments
Bridge.7z
(141.83 KiB) Downloaded 60 times

shiRo
Posts: 20
Joined: Thu Oct 12, 2023 8:55 am

Re: Failure to run analysis

Post by shiRo » Tue Nov 19, 2024 2:15 am

Supplementary explanation : I ignore the properties of the zero length unit, and there is no longer a prompt error after changing the ' 2D ' to ' 3D ', but there is still a convergence problem.

STKO Team
Posts: 3066
Joined: Tue Oct 29, 2019 8:45 am

Re: Failure to run analysis

Post by STKO Team » Tue Nov 26, 2024 9:30 am

Issues:
  • The fiber section for the Deck does not have -GJ (torsional stiffness) -> force beam element cannot invert flexibility matrix
  • One of the piers is missing fixities
  • Deck fiber section does not have steel, and its concrete has zero tensile strength -> cannot invert flexibility as nothing is reacting in tension
  • The zeroLength elements (springs) at the 2 extremities of the Deck are discretized in 2 elements each one -> singularity (use only 1 mesh per spring)
  • The zeroLength elements (springs) at the 2 extremities of the Deck are missing materials in the local Y Z rotational DOFs. Without those the deck are some rigid body rotations

Post Reply