In the previous exercise we ran a buckling analysis which consisted of two separate analysis Load Steps. The first step was a static loading with a unit compression load. The second step performed the actual buckling analysis and determined the critical buckling as a factor of the unit compression load. The first analysis step was associated to a load case which contained the boundary conditions and the compression load. However the second step was associated with a load case that only had the boundary conditions. This exercise has been designed to help you understand how Marc deals with loads and the proper way to set them up in Patran.

In Marc, generally speaking, once a structure has been loaded, that load remains until it changes or is removed. So, in the previous exercise, the first step applied a unit compressive load. In the second step it appeared to have been removed. Although the physical load was not placed in the load case, that actual load level remained the same from the first step to the next. In order for that load to be removed, it would have had to have been explicitly taken down to zero.

In this exercise we will set up and run two different static runs to illustrate how loads are handled.