Copyright 2025 by Space Gass Pty Ltd
SPACE GASS performs numerous checks for illegal and inconsistent data. Many of these checks are done in the data input modules and any errors detected there must be corrected immediately. However, some errors and warnings such as instabilities and ill-conditioning cannot be detected until the analysis phase.
If any errors in the data are detected, SPACE GASS lists them on the screen, aborts the analysis and then returns to the main menu, ready for correction of the offending items. Warnings are displayed at the end of the analysis and do not cause it to abort.
Node # not found for member #
A member is connected to a non-existent node.
Direction node # not found for member #
A member has referenced a non-existent direction node.
Section # not found for member #
A member has referenced a non-existent section property.
Section # has impractically large section properties for the frame size
The properties of a section are too large for the frame dimensions. This error is often due to the section properties being input in the wrong units.
Material # not found for member #
A member has referenced a non-existent material property.
Member # has zero length
A member is connected to two nodes with identical coordinates.
Restraint applied to non-existent node #
A restraint has been applied to a node which doesn’t exist.
Slave node # not found
A non-existent node has been specified as a slave node.
Master node # not found for slave node #
A non-existent node has been specified as a master node.
A constraint has been applied to a restrained DOF on node #
Any restrained degrees of freedom for a slave node cannot be constrained to a master node.
Node # has been specified as both slave and master
A master node cannot be the slave of another master node.
Member # with PA<>0.0 must have identical Y and Z axis fixities at an end
Because of the difficulty involved in calculating the stiffness matrix for a member with a non-zero principal angle when the member end fixities are about its non-principal axes, the Y and Z fixities at an end must be the same.
Cable member # must not have any translational fixities released
For stability, cable members must have all of their translational fixities fixed.
Cable member # must not have member offsets
Cable members cannot have member offsets.
Cable member # must not have semi-rigid joints
Cable members are always assumed to be pin-ended, and hence cannot have semi-rigid joints.
Member # must not have shear fixity released with semi-rigid joints
Members with semi-rigid joints cannot have shear fixities released. This restriction only applies when the semi-rigid joint and the shear fixity act in the same plane.
Node load on non-existent or dummy node #, load case #
A node load has been applied to a non-existent node.
Prescribed displacement on non-existent or dummy node #, load case #
A prescribed displacement has been applied to a non-existent node.
Concentrated load on non-existent member #, load case #
A concentrated member load has been applied to a non-existent member.
Distributed force on non-existent member #, load case #
A distributed member force has been applied to a non-existent member.
Distributed torsion on non-existent member #, load case #
A distributed member torsion has been applied to a non-existent member.
Prestress load on non-existent member #, load case #
A prestress load has been applied to a non-existent member.
Prescribed displacement applied to end of cable member #, load case #
Nodes at the ends of cable members must not have prescribed displacements applied to them.
Prescribed displacement applied to released restraint on node #, load case #
Prescribed displacements can only be applied to node degrees of freedom which are restrained.
Prescribed displ. applied to master constraint DOF on node #, load case #
Prescribed displacements must not be applied to master node degrees of freedom which are constraining a slave node.
Concentrated load is off the end of member #, load case #
A concentrated member load has been located beyond the ends of the member.
Concentrated load applied to cable member #, load case #
Concentrated member loads must not be applied to cable members.
Distributed force is off the end of member #, load case #
A distributed member force has been located beyond the ends of the member.
UDL must act over full length of cable member #, load case #
Uniformly distributed loads applied to cable members must act over the entire cable length.
Trapezoidal load applied to cable member #, load case #
Distributed trapezoidal loads must not be applied to cable members.
Distributed torsion is off the end of member #, load case #
A distributed member torsion has been located beyond the ends of the member.
Distributed torsion applied to cable member #, load case #
Distributed torsion loads must not be applied to cable members.
Load case # has been specified as both primary and combination
Load cases can be primary or combination, but not both.
Combination # contains non-primary load case #
Combination load cases can only be made up from primary load cases. Combination load cases cannot be further combined.
None of the load cases selected exist
There are no valid load cases in the load cases list selected for analysis.
Insufficient space on drive C, # bytes extra required
The analysis module has detected that there is not enough space left on the hard disk for the analysis to run to completion. Extra space equal to the number of bytes shown is required. You should terminate the analysis, remove any unwanted data files or programs and then try the analysis again.
Cable member # is ill-conditioned in load case #
The program was unable to accurately calculate the cable geometry and stiffness matrix.
Member # has buckled in load case #, axial load = 123.23. Continue?
During a non-linear analysis, the program was unable to calculate the stiffness matrix for the member because its Euler buckling load was exceeded. If you continue, the member is simply disabled for the rest of the analysis iterations. Note that this message is the result of a simple local member buckling check only. Overall frame buckling or buckling of multiple members is not considered! The local member buckling messages can be suppressed by clearing the appropriate check box at the start of the analysis.
Instability found at member # in load case #
An instability has been detected at a specified member. The instability could be located at either end of the member.
Not all load steps were completed
The load was applied in more than one step, however it was stopped before all steps were completed. Because the full load was not reached, the results cannot be used for the load cases being analysed.
WARNING: Possible ill-conditioning detected, check reactions
Ill-conditioning may have been detected. If the reactions equal the applied loads then no ill-conditioning has occurred. This message is only a warning which can be suppressed from the output reports if necessary.
WARNING: Analysis did not reach desired convergence in all load cases
The level of convergence in a non-linear analysis has not reached the required convergence accuracy for some load cases. This is not necessarily fatal if the convergence achieved is close to that requested. Note also that some of the load cases may have fully converged and this can be checked by looking at the output reports.
Copyright 2025 by Space Gass Pty Ltd