In　order　to　investigate　the　vertical　vibration　characteristics　of　large-diameter　pipe　piles　embedded　in　bidirectional　inhomogeneous　soils,　a　mechanical　model　for　longitudinal　vibration　of　large-diameter　pipe　piles　in　radial　inhomogeneous　layered　soils　is　established　by　considering　the　lateral　inertia　effect　of　large-diameter　pipe　piles　and　construction　disturbance,　based　on　the　Rayleigh-Love　rod　model　and　Novak＇s　plane-strain　theory.　The　complex　stiffness　expression　at　the　interface　between　the　soil　and　the　large-diameter　pipe　pile　is　obtained　recursively　by　means　of　the　Laplace　transform　and　complex　stiffness　transfer　techniques.　Then　the　analytical　solution　for　the　dynamic　impedance　of　large-diameter　pipe　piles　is　derived　by　using　the　completely　coupling　condition　between　pile　and　soil　and　the　transitivity　of　the　impedance　function,　and　compared　with　the　previous　solutions　to　verify　the　validity　and　precision.　Furthermore,　parametric　analyses　are　performed　to　investigate　the　effects　of　the　parameters　of　pile　and　soil　on　the　dynamic　impedance　of　a　large-diameter　pipe　pile.　The　results　show　that　the　Rayleigh-Love　rod　model　and　the　relevant　analytical　solution　are　more　appropriate　to　analyze　the　longitudinal　vibration　characteristics　of　large-diameter　pipe　piles　than　Euler-Bernoulli　rod　model　which　underestimates　the　amplitude　and　resonance　frequency　of　the　dynamic　impedance.　Keeping　the　inner(outer)　diameter　constant,　the　larger(smaller)　the　outer(inner)　diameter,　the　higher　the　amplitude　and　resonance　frequency　of　the　dynamic　impedance　at　the　pile　head.　The　softer(harder)　the　longitudinal　interlayer　of　the　surrounding　soil,　the　larger　the　peak　difference　of　the　dynamic　impedance　curves.　The　greater　the　degree　of　softening(hardening)　of　the　surrounding　soil,　the　larger(smaller)　the　amplitude　and　resonance　frequency　of　the　dynamic　impedance　at　the　pile　head.　The　disturbance　range　has　a　significant　effect　on　the　oscillation　amplitude　while　little　influence　on　the　resonance　frequency.　©　2021,　Science　Press.　All　right　reserved.