Another way to export a model is to use the direct link between ArchiCAD and another software application. This means that a specific Add-On (developed by other applications for use with ArchiCAD) converts the ArchiCAD elements (e.g. the structural elements) to the corresponding elements of the connected application. This exchange mode also ensures that only those properties needed by the target application are included in the resulting model file.
Ask your partner if his/her application has an available Add-On for ArchiCAD.