What is P-delta , P-Delta Effects and P-Delta Analysis Parameters
What is P-delta & P-Delta effects? P-Delta effect, also known as geometric non-linearity, involves the equilibrium and compatibility relationships of a structural system loaded about its deflected configuration. Of particular concern is the application of gravity load on laterally displaced multi-story building structures. This condition magnifies story drift and certain mechanical behaviors while reducing deformation capacity. P-Delta effect typically involves large external forces upon relatively small displacements. If deformations become sufficiently large as to break from linear compatibility relationships, then Large-Displacement and Large-Deformation analyses become necessary. The two sources of P-Delta effect are illustrated in Figure 1, and described as follows: P- effect, or P-“small-delta”, is associated with local deformation relative to the element chord between end nodes. P-Delta analysis parameters in Etabs Initial P-Delta analysis may be specified in ETABS via Defi