You seem to be asking multiple questions. It is clear that you want to turn the printed information from the truss manufacturer into something that could be used inside Revit. It is somewhat unclear what you need to import into the drawing (vector geometry, text information, or just image data) and what kind of Revit geometry you are creating (generic model, analytic truss, detail component, etc., or drafting view). It seems like you may want to use Dynamo to recreate the truss given the truss information using json data structures. I would be very interested in how you expect to do that reliably even from a single page. <aside>I've had very poor results integrating any truss elements as analytical trusses on my projects and now use detail components to make section and callout views look realistic rather than dorky rectangular assemblies.</aside>
The most obvious question that I can answer is "Can I import more than one page at a time into AutoCAD?". You can customize with LISP to batch either the -pdfattach or -pdfimport commands, not PDFATTACH OR PDFIMPORT. If you use -pdfimport, the geometry can be imported and converted at the same time. If you use -pdfattach, you would need to follow up with -pdfimport to convert. <aside> Why you want all the trusses printouts to go in the same drawing is a bit of a mystery.</aside> The -pdfimport command could be used within a LISP to place any number of sheets from a file and to convert them, making it appear to be a one step operation. <aside>I often batch import multiple pdf pages into a single drawing for specs and code compliance sheets like Appendix B. My process is Word document->PDF ->AutoCAD. I plot the AutoCAD sheets and merge them with the Revit sheets.</aside>
You still have the problems I discussed before. The geometry will not be at a consistent scale or may be not to scale at all. Also, the imported text (dimensions and notes) may be text after importation but will probably be merely lines, which can't be programmatically interpreted.
Good luck. I'd be very interested in learning the process of converting vector data into Revit trusses.
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