The　adoption　of　innovative　H-shaped　prestressed　UHPC　piles　presents　a　promising　avenue　for　integral　abutment　bridges　(IBAs),　addressing　concerns　related　to　the　high　horizontal　stiffness　of　conventional　concrete　piles　and　the　cost　and　durability　challenges　associated　with　steel　piles　in　this　bridge　typology.　In　this　study,　two　common　Hshaped　section　orientations　(weak　and　strong　axis)　were　investigated　to　elucidate　the　mechanical　properties,　crack　propagation　mechanisms,　failure　modes,　and　ultimate　load-bearing　capacities　of　H-shaped　prestressed　UHPC　(H-PU)　members　under　weak　and　strong　axis　bending,　respectively.　A　notable　discrepancy　in　stiffness　and　strength　was　observed　between　members　oriented　along　the　strong　and　weak　axis.　Subsequently,　a　simplified　calculation　method　was　developed　to　accurately　predict　cracking　and　ultimate　moments.　The　impact　of　geometric　parameters　on　bending　capacity　were　analyzed　through　the　proposed　calculation　method,　providing　valuable　insights　for　optimizing　structural　design.　And　the　applicability　of　this　calculation　method　was　further　verified　by　finite　element　expanded　parameters　analysis,　the　results　showed　that　the　calculation　method　demonstrated　a　high　level　of　accuracy.　Finally,　the　bending　performance　of　H-PU　member　was　compared　with　that　of　H-shaped　steel　member　and　solid　square　prestressed　traditional　concrete　(S-PC)　member,　providing　contextual　understanding　of　their　structural　suitability　and　potential　advantages.