The　machine　bed　and　the　concrete　foundation　are　connected　by　anchor　bolts.　Foundation　creep　is　a　comprehensive　manifestation　of　foundation　stability.　The　size　and　change　of　foundation　creep　affect　the　dynamic　characteristics　of　the　bed-foundation　interface　and　the　working　state　of　heavy　machine　tools.　In　this　paper,　the　contact　problem　between　bed　and　foundation　made　of　heterogeneous　materials　is　solved,　a　concrete　crushing　hypothesis　is　proposed,　and　the　basis　for　determining　the　elastic-elastoplastic-crushing　critical　deformation　parameters　of　the　concrete　surface　is　formulated.　Based　on　the　Hertz　contact　and　fractal　theories,　an　equivalent　contact　model　of　the　joint　is　developed,　revealing　the　nonlinear　mechanical　behavior　of　the　bolted　contact　surface.　The　cement　hydration　and　foundation　creep　factors　under　continuous　loading　are　taken　simultaneously　into　consideration,　and　the　change　trend　of　the　compressive　strength　and　elastic　modulus　of　the　concrete　at　the　later　stage　of　loading　is　determined.　By　comprehensively　analyzing　the　simulation　and　experimental　results,　the　error　of　the　theoretical　model　was　found　to　be　within　10%,　which　verifies　the　correctness　of　the　proposed　theoretical　model.　Finally,　by　assuming　that　the　external　load　remains　unchanged,　a　contact　stiffness　prediction　model　based　on　foundation　creep　is　developed,　which　can　provide　a　new　basis　for　the　contact　modeling　of　bed-concrete　foundation　joint　surfaces.