The　purpose　of　this　study　is　to　develop　a　systematic　meso-level　theoretical　modeling　approach　for　analyzing　the　mode-I　fracture　failure　behaviors　of　concrete.　Firstly,　the　crack　model　is　developed　in　a　way　to　be　equivalent　to　the　continuum　model　at　the　macro-level.　Secondly,　an　extended　universal　morphological　model　(XUMM)　for　concrete　mode-I　fracture　analysis　is　proposed　at　the　meso-level.　Afterwards,　both　the　mesoscopic　fracture　characteristics　and　the　macroscopic　mechanical　parameters　of　concrete　are　theoretically　deduced　based　on　the　proposed　XUMM.　Comparison　with　existing　meso-level　test　results　shows　that　the　predictions　from　the　XUMM　have　good　consistency,　but　offsets　are　obvious　as　well.　At　last,　the　XUMM　is　calibrated　using　the　limit　state　method　and　preliminarily　verified　via　mesoscale　numerical　simulations.