The Arclength method is a numerical method used in finite element analysis (FEA) to solve non-linear problems. It is based on the concept of incremental loading, where the structure is subjected to small incremental loads and the response is computed at each step. This method is particularly useful for problems with large deformations or material non-linearity.
The Arclength method differs from other methods in non-linear FEA, such as the Newton-Raphson method, in that it does not require the computation of the tangent stiffness matrix. Instead, it uses a secant stiffness matrix, which is updated at each load increment. This makes it more efficient for problems with large deformations or material non-linearity.
The Arclength method has several advantages over other methods in non-linear FEA. It is more stable and robust, as it does not require the computation of the tangent stiffness matrix, which can be prone to numerical instabilities. It also converges faster for problems with large deformations or material non-linearity.
The Arclength method is not suitable for problems with large displacement gradients or severe material non-linearity. It also requires a relatively small load increment size to ensure accuracy, which can increase computation time.
The Arclength method is implemented in non-linear FEA software by using an incremental loading approach and updating the secant stiffness matrix at each load increment. The software also includes algorithms to handle convergence issues and adjust the load increment size if needed. Users can select the Arclength method as an option in the software's non-linear analysis settings.