Featured　Application　Potential　applications　of　this　work　include　predicting　the　stable　stress　and　strain　fields　and　analyzing　the　influence　factors　of　frost　heave　force　and　deformation　of　soil　surfaces　after　freezing　processes.　In　analyzing　frost　heave,　researchers　often　simplify　the　compressive　modulus　of　freezing　soil　by　considering　it　as　a　constant　or　only　as　a　function　of　temperature.　However,　it　is　a　critical　parameter　characterizing　the　stress-strain　behavior　of　soil　and　a　variable　that　is　influenced　by　many　other　parameters.　Hence,　herein　several　one-dimensional　freezing　experiments　are　conducted　on　silty　clay　in　an　open　system　subjected　to　multistage　freezing　by　considering　the　compressive　modulus　as　a　variable.　First,　freezing　soil　under　multistage　freezing　is　divided　into　several　layers　according　to　the　frozen　fringe　theory.　Then,　the　correlation　between　the　freezing　rate　and　temperature　gradient　within　each　freezing　soil　layer　is　investigated.　Takashi＇s　equation　for　frost　heave　analysis　is　modified　to　extend　its　application　conditions　by　replacing　its　freezing　rate　term　with　a　temperature　gradient　term.　A　mechanical　model　for　the　stress-strain　behavior　of　freezing　soil　under　the　action　of　frost　heave　is　derived　within　the　theoretical　framework　of　nonlinear　elasticity,　in　which　a　method　for　determining　the　compressive　modulus　of　freezing　soil　with　temperature　gradient,　overburden　pressure,　and　cooling　temperature　variables　is　proposed.　This　study　further　enhances　our　understanding　of　the　typical　mechanical　behavior　of　saturated　freezing　silty　clay　under　frost　heave　action.