To all Etabs master, any body encounter this message in the run analysis: NEGATIVE JACOBIAN ENCOUNTERED. Please tell me hiw to solve this issue thanks.
A negative jacobian is when, to the program, an negative volume is defined for the FEA analysis. If you have really skinny elements, the nodes are closer than the programs specified tolerance, or the shape is defined incorrectly, you will get the error.
I am not an ETABs user, so I dont know the debugging process per se, but if you can try to view the mesh, or if it tells you what element is the problem, thats a good place to start. if you can adjust the nodal tolerance in mesh settings that may also help.