1. What is the different between P-Delta Analysis and Geometric Nonlinearity Analysis?
2. If the Stiffness is changed in P-Delta Analysis?
3. When the Geometric Nonlinearity Analysis is prior to use?
4. Which method is used to solve the Geometric Nonlinearity equation in STAAD?
Pdelta analysis is used to account for secondary forces generated due to large and small delta effects. A nonlinear analysis is used for problems where there is a significant deformation due to which the structural stiffness needs to be recalculated based on the deformed geometry. Nonlinear analysis includes both large and small delta effects.
STAAD.Pro supports two types of Pdelta analysis. The recommended one is the iterative Pdelta ( PDELTA nn ANALYSIS ) in which the software iteratively modifies the force vector and NOT the stiffness matrix. There is a PDELTA KG ANALYSIS that is another option which accounts for the second order effects by modifying the stiffness matrix but it cannot be used for all situations. Please refer to the help documentation for more details.
I assume you are asking when to use Geometric Nonlinear Analysis. It can be used for problems where there is significant structural deformation.
Newton Raphson method is used.
Answer Verified By: Str Stu