Hi -Not sure what you are after, I would convert the TIN to a raster then the raster to a shape �??point' file with the points giving elevations or whatever the TIN is representing.
It depends on the shapefile you are looking for. You can harvest the nodes, edges, domain or TIN Triangles. It just depends on what you are trying to achieve. Otherwise the raster will best represent the surface if contour generation is what is desired.