exporting DWG from ArcMap need to unify segments to polylines

Question

I am a green ArcGIS user so please bear with my poor nomenclature and rudimentary understanding of the software........

I am attempting to export to CAD a contour shapefile I have derived from LIDAR imagery. Once exported I bring the contour DWG into ArchiCAD, drag ' drop, boom it opens. All good.......except:

Any curves are broken down into thousands of single small co-joined lines, and unlike Autocad I don't have an effective-efficient way to polyline edit......make continuous sections into single polylines or splines as they'd be referred to in ArchiCAD.

Is there a way to set up my shapefile, edit or geoprocess it prior to export that will net me what I am after?

Thanks in advance!