Analysis Control - Nonlinear Static
<Analysis Control-Nonlinear> Scheme Specify non-linear analysis method Constant Stiffness Method A method of convergence towards the solution with the constant stiffness during the iterative analysis process. The constant stiffness refers to the elasticity. Secant Method A method of convergence towards the solution by the origin direction stiffness during the iterative analysis process. Newton Raphson Method A method of convergence towards the solution by the tangent stiffness of the load-displacement diagram during the iterative analysis process. Modified Newton Raphson Method A method of executing the current stage iterative analysis by using the stiffness of the previous stage load step Maximum Number of Iterations/Load Step Maximum number of iterations for analysis per Load Step. Include Line Search When performing iterative methods, the include line search is an algorithm which accelerates the speed of convergence. However, in cases of material non-linear analysis, the speed may be reduced significantly. Convergence Criteria Specify the basis on which to assess the convergence. If multiple criteria are chosen, then all of them must be satisfied to establish the convergence. Energy Norm Assess the convergence on the basis of Energy (Member force x displacement) Norm. Displacement Norm Assess the convergence on the basis of Displacement Norm. Force Norm Assess the convergence on the basis of Member Force Norm. Stepping procedures Setting the load step process Manual with Equidistance Steps The load are divided into a number of increments based on the number of load increments. Summation of load factor must equal to one. User Defined Steps Load increment size can be manually inputted by user. Negative Load factors or factors greater than one can be inputted. Automatic Load Step Automatic load steps are calculated by the solver. If a particular stages fails to converge, the initial load factor is reduced by 25% and the analysis is performed again using the reduced load increment. Analysis will terminate if the load factor is less than the minimal load factor or if the number of iterations is greater than the assigned value. Arc Length Method In the load-displacement diagram, the Arc Length Method recognizes length increments of the segment as an arc length, and this method, by putting a limit to the specified length, finds the nonlinear solution. Save Step Specify options for saving result data. Last Step This option saves only the last load step in the result file. All Step This option saves all the load steps in the result file. User Defined Load Step The above defined Iteration Method is applied individually to load cases. Skip Nonlinear Analysis It perform true linear analysis, not repeating the processes of nonlinear analysis. <Add/Modify Analysis Case-Static-User Defined Load Step> Step Number of Load Steps entered. Load Factor Load factors for each increment. Save Step It saves the result data in the output file at the stage.

Analysis Control - Nonlinear Static

Scheme

Specify non-linear analysis method

Constant Stiffness Method

A method of convergence towards the solution with the constant stiffness during the iterative analysis process. The constant stiffness refers to the elasticity.

Secant Method

A method of convergence towards the solution by the origin direction stiffness during the iterative analysis process.

Newton Raphson Method

A method of convergence towards the solution by the tangent stiffness of the load-displacement diagram during the iterative analysis process.

Modified Newton Raphson Method

A method of executing the current stage iterative analysis by using the stiffness of the previous stage load step

Maximum Number of Iterations/Load Step

Maximum number of iterations for analysis per Load Step.

Include Line Search

When performing iterative methods, the include line search is an algorithm which accelerates the speed of convergence. However, in cases of

material non-linear analysis, the speed may be reduced significantly.

Convergence Criteria

Specify the basis on which to assess the convergence. If multiple criteria are chosen, then all of them must be satisfied to establish the convergence.

Energy Norm

Assess the convergence on the basis of Energy (Member force x displacement) Norm.
Displacement Norm

Assess the convergence on the basis of Displacement Norm.
Force Norm

Assess the convergence on the basis of Member Force Norm.

Stepping procedures

Setting the load step process

Manual with Equidistance Steps

The load are divided into a number of increments based on the number of load increments. Summation of load factor must equal to one.

User Defined Steps

Load increment size can be manually inputted by user. Negative Load factors or factors greater than one can be inputted.

Automatic Load Step

Automatic load steps are calculated by the solver. If a particular stages fails to converge, the initial load factor is reduced by 25% and the analysis is performed again using the reduced load increment. Analysis will terminate if the load factor is less than the minimal load factor or if the number of iterations is greater than the assigned value.

Arc Length Method

In the load-displacement diagram, the Arc Length Method recognizes length increments of the segment as an arc length, and this method, by putting a limit to the specified length, finds the nonlinear solution.

Save Step

Specify options for saving result data.

Last Step

This option saves only the last load step in the result file.
All Step

This option saves all the load steps in the result file.

User Defined Load Step

The above defined Iteration Method is applied individually to load cases.

Skip Nonlinear Analysis

It perform true linear analysis, not repeating the processes of nonlinear analysis.

Step

Number of Load Steps entered.
Load Factor

Load factors for each increment.
Save Step

It saves the result data in the output file at the stage.