The　time　required　for　detailed　modelling　of　the　soil-substructure　interaction　(SSI)　in　the　Integral　abutment　bridge　(IAB)　is　considerable,　especially　for　the　soil-pile　interaction　(SPI).　A　simplified　modelling　method　that　could　replace　the　detailed　modelling　of　piles　and　the　corresponding　SPI　in　the　IAB　by　using　an　equivalent　soil-pile　system　set　at　the　abutment　base　under　uniform　temperature　variations　(∆Tu)　of　±25°C　was　numerically　investigated.　Under　the　∆Tu　of　+25°C,　the　equivalent　soil-pile　system　for　the　abutment　with　a　height　of　5.0　m　to　7.0　m　or　with　a　height　of　3.0　m　to　4.5　m　can　be　simulated　by　a　translative　spring　and　a　rotational　spring　or　a　translative　spring　and　a　compulsory　rotation　angle,　respectively.　Under　the　∆Tu　of　-25°C,　the　equivalent　soil-pile　system　can　be　simulated　by　a　translative　spring　and　a　compulsory　rotation　angle.　The　influence　of　different　abutment　heights　and　thicknesses　on　the　stiffness　of　the　equivalent　soil-pile　system　was　studied.　©　2025　IABSE　Symposium　Tokyo　2025:　Environmentally　Friendly　Technologies　and　Structures:　Focusing　on　Sustainable　Approaches　-　Report　All　rights　reserved.