Deformation from load case

Deformation from load case is one of the ways how to define the initial global geometrical imperfection.

In this case, the initial imperfection is defined by the deformation shape (and size) of specific load case (more precisely by the nonlinear analysis which contains that specific load case - analysed by 3rd order, as noted in the brackets). The size (and direction) then might be altered by the multiplier (default value = 1).

There is expected difference in behaviour sinceSCIA Engineer 24.0 !

Before SCIA Engineer 24.0, the initial imperfection shape and size was practically the same as deformation of the linear analysis of the corresponding load case.

Since SCIA Engineer 24.0, the initial imperfection is determined based on a results of background nonlinear analysis which contains the corresponding load case. For example, if there is GI based on LC2 with multiplier 1 - there is a background analysis (3rd order) of a nonlinear combination with content of 1*LC2. Based on this result, the GI is defined. Hence, there might be little differences, between linear analysis of the load case LC2 and GI, which is based on LC2 with multiplier 1.

Example is provided in the figure below. The differences might be also larger, depends on the applied load and structure stiffness.