The presence of unsupported elements in the structural analysis models causes the formation of mechanisms and the inability to solve the equilibrium equations.

Since singularity occurs in the stiffness matrix of the structure, its determinant becomes zero and the matrix cannot be reversed.
Since the traditional Solver solves the equilibrium equation system with the 'Gauss-Jordan Elimination' method and the data is prepared accordingly, it can specify exactly at which node the mechanism formation is. In this case, the program can find the problematic node numbers.

On the other hand, the Sparse equation solver uses different hiding and inverting algorithms to hold and invert symmetric matrix data, which is usually zero, and factorize it. It is faster by the algorithm and has less memory requirement. However, as a disadvantage, it cannot give the exact address of the node where the problem is experienced.

In cases where the problematic node cannot be detected, we can cancel the 'Sparse Equation Solver' and find out which nodes have problems.

The video explains how to proceed in case of a mechanism in the structural analysis model.

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