This　study　investigates　the　printability　and　mechanical　properties　of　3D　printed　recycled　sand　concrete　(3DPRSC)　based　on　different　silica　fume　(SF)　contents　(5　%,　10　%,　15　%,　20　%),　PVA　fiber　(PVAF)　contents　(0.5　%,　1　%,　1.5　%),　and　basalt　fiber　(BF)　contents　(0.1　%,　0.3　%,　0.5　%).　Further,　based　on　the　uniaxial　compression　test,　the　uniaxial　compression　constitutive　model　for　3DPRSC　is　proposed,　considering　the　effects　of　varying　SF,　PVAF,　and　BF　contents.　Finally,　the　microstructure　mechanism　is　explained　through　microscopic　tests.　The　results　show　that　adding　1.0　%　PVAF　and　0.3　%　BF　significantly　enhances　compressive　and　splitting　tensile　strength　of　3DPRSC.　With　the　increase　of　SF,　the　characteristic　values　of　3DPRSC　generally　increase　first　and　then　decrease.　The　addition　of　PVAF　enhances　the　peak　stress,　peak　strain,　and　ultimate　strain　of　3DPRSC,　while　BF　has　a　lesser　impact　on　these　characteristic　values.　The　fitting　results　of　the　proposed　uniaxial　compression　constitutive　model　align　well　with　the　stress-strain　curves.　After　adding　fibers,　fluctuations　in　the　ascending　branch　were　reduced,　and　the　descending　branch　became　smoother.　Microscopic　experiments　indicate　that　an　appropriate　amount　of　SF　can　enhance　the　compressive　and　splitting　tensile　strength　of　3DPRSC.　A　suitable　content　of　fiber　can　form　a　directional　distribution　of　networks　inside　3DPRSC,　enhancing　its　mechanical　properties,　but　excessive　fiber　content　will　cause　fiber　agglomeration　and　lead　to　more　harmful　pores　inside　3DPRSC　while　amplifying　mechanical　anisotropy.　These　research　results　can　provide　an　important　theoretical　basis　for　the　design　of　3DPRSC.　©　2025　Elsevier　Ltd