Jointless　bridge　has　been　proved　to　be　a　costeffective　alternative　to　bridges　with　conventional　joints.　The　longitudinal　thermal　movement　of　the　superstructure　is　usually　considered　as　the　key　parameter　for　designing　jointless　bridges.　The　average　temperature　of　crosssections　can　be　considered　as　the　effective　temperature　of　the　superstructure.　In　order　to　accurately　estimate　the　longitudinal　thermal　movement　of　the　superstructure,　the　average　temperature　of　crosssections　should　be　obtained.　The　temperature　distribution　on　crosssections　of　Tshaped　girders　in　one　jointless　bridge　was　monitored.　A　finite　element　model　was　implemented　using　the　MIDASFEA　software,　which　is　verified　based　on　the　monitoring　results.　Considering　the　historical　extreme　temperature　conditions　and　the　results　of　the　parametric　study,　the　peak　values　of　the　average　temperature　of　Tshaped　girder　crosssections　for　jointless　bridges　in　different　climate　regions　in　China　are　recommended.　Finally,　the　simplified　formulae　to　predict　the　effective　temperatures　of　Tshaped　girder　crosssections　for　jointless　bridges　are　proposed　based　on　the　correlation　analysis.　©　20th　Congress　of　IABSE,　New　York　City　2019:　The　Evolving　Metropolis　-　Report.　All　rights　reserved.