step manager 里的OP option =NEW 问题

abaqus中 一旦设置OP option =NEW ，会默认把前面step的边界条件都inactive，所以你设置一个load collector里面 会发现其他的 load collectors里面也会变为New。

Be very careful when you use the OP=NEW parameter on the *BOUNDARY option to remove a boundary constraint from your model. All boundary constraints are removed from the model, not just the one you want removed; therefore, you must respecify all the boundary conditions that should remain active in the model. Remember that the boundary conditions that you specify must provide enough constraints to prevent rigid body motions in all components of your model. Failure to do so will cause Abaqus to issue numerical singularity warnings and leads to excessive displacements.