In an imperfection case of the type 'Group of Imperfection Cases', you can combine previous imperfection cases in a linear way. There are the combinations of the types ' AND' and 'OR'. In addition, the factor of each imperfection case can be specified or defined by a formula.
Hence, you can use this imperfection type to consider the reverse imperfection direction of each previously created imperfection case. For an imperfection case, enter the factor '-1.0' in the combination.
Also, this imperfection type allows you to superimpose multiple imperfection directions to consider the most unfavorable case of imperfections. Use the combination with the keyword 'OR'. All possible sub-combinations are created automatically.
Another application is the superposition of different imperfection types. For example, you can superimpose a global inclination generated by using member imperfections with a local member imperfection based on the buckling mode.
