In　the　current　study,　a　Short-Term　Thermal　Creep　Strain　(STTCS)　model　of　concrete　was　innovatively　developed.　This　model　can　predict　the　time-dependent　deformation　of　concrete　subjected　to　wide　applied　load　level　ranging　from　20　%　to　60　%　and　temperatures　up　to　900　°C.　A　creep　compliance　function　was　developed　to　study　the　nonlinear　creep　characteristics　of　concrete　with　creep　parameters.　The　definition　and　sensitivity　of　the　creep　parameters　were　investigated.　In　order　to　comprehensively　predict　the　performance　of　concrete　subjected　to　multiaxial　compressive　loads　in　fire,　an　orthotropic　triaxial　compression　thermo-mechanical　damage　model　for　concrete　is　developed.　The　influence　of　STTCS　on　the　multiaxial　stress-strain　behaviors　was　taken　into　account　in　the　multiaxial　model.　The　coupling　thermo-mechanical　contributions　containing　the　development　of　STTCS　with　thermal　effect,　stress　confinement,　plastic　damage　and　hardening　evolution　were　creatively　considered　in　the　potential　function　within　thermodynamics　framework.　The　sensitivity　of　yield　surface　was　discussed.　The　numerical　operations　of　this　proposed　model　were　conducted　for　validation.　The　nonlinear　stress-strain　responses　of　concrete　were　accurately　captured　at　temperatures　ranging　from　20　°C　to　800　°C　through　the　comparative　study　with　test　results　in　literatures,　which　indicates　the　accuracy　and　applicability　of　the　proposed　model.　©　2024　Elsevier　Ltd