The　stress　of　pier-beam　connections　of　Ⅰ-shaped　steel-concrete　composite　rigid　frame　bridges　is　complex，the　force　transmission　mechanism　and　load　distribution　of　pier-beam　joints　are　still　unclear，and　the　calculation　method　of　pier-beam　joints　is　lacking.　By　comparing　the　test　results　of　the　pier-beam　joints　of　the　Ⅰ-shaped　composite　rigid　frame　bridges，the　verified　solid　finite　element　calculation　model　is　adopted.　According　to　the　stress　state　of　each　component　of　the　pier-beam　joint　under　the　action　of　the　axial　force，bending　moment　and　shearing　force　of　the　pier，the　force　transmission　mechanism　and　load　bearing　ratio　of　the　pier-beam　joint　are　analyzed.　The　design　calculation　method　of　each　component　is　established，and　the　trial　design　of　the　Ⅰ-shaped　composite　rigid　frame　bridge　is　carried　out.　The　results　show　that　the　force　transmission　mechanism　and　path　of　axial　force　and　bending　moment　are　similar，and　the　shearing　force　transmission　mechanism　is　different.　The　longitudinal　beam　and　the　transverse　beam　bear　45%~55%　of　the　load　transfer，respectively.　Under　the　action　of　axial　pressure　and　axial　tension，the　load　transfer　path　and　the　load　bearing　proportion　of　the　longitudinal　beam　change.　The　load　directly　transmitted　by　the　longitudinal　beam　is　mainly　transmitted　through　the　lower　flange　of　the　longitudinal　beam，and　the　load　transmitted　to　the　transverse　beam　is　mainly　borne　by　the　studs　of　the　web.　The　design　of　the　longitudinal　beam　should　consider　the　additional　stress　of　the　pier　load.　The　transverse　beam　is　calculated　according　to　the　uniform　load　force　mode　of　the　simply　supported　beam.　The　design　of　the　transverse　beam　web　connector　is　calculated　according　to　the　load　transferred　to　the　transverse　beam.　The　studs　of　the　longitudinal　beam　web　and　lower　flange　are　arranged　by　structural　requirements.　The　pier-beam　joint　of　trial　design　bridges　meets　the　requirements.　The　finite　element　calculation　results　are　consistent　with　the　theoretical　calculation　results.　The　established　pier-beam　joint　design　method　can　be　applied　to　the　design　of　Ⅰ-shaped　composite　rigid　frame　bridges.　©　2025　Hunan　University.　All　rights　reserved.