Node-Tet constraint with Penalty zero mass error

[alnagm]

Hi,

I created a node list that is common between beams with and without stirrup reinforcement. When i ran the beam with all reinforcement, it went smooth as it was in the older versions. When i dont define all beam elements for stirrups, some of the nodes in the rebar node list become completely disconnected, in previous versions this was running without problems. After updating i get this message

Found zero nodal mass in node-tet constraints (Penalty).
Check mass in tet list.

The penalty based on time step on Youngs modulus dont work, the only one that works is with direct stiffness as an input. Is it ok to change this from Error to warning and allow the program to contineue

[zhouxinwei]

When we define node-tet constraints (penalty), MARS checks the mass and make sure the nodes in the node list have non-zero mass.

In a case where the node list has free nodes (not used in element definition), these nodes won't be initialized or given mass. This is the error reported. The solution is to remove these free nodes.