To　investigate　the　performance　degradation　of　reinforced　concrete　bridges　under　multiple　factors,　the　time-dependent　evolution　process　of　its　resistance　and　reliability　was　studied.　The　effects　of　carbonization,　chloride　accumulation,　load,　and　crack　on　chloride　ion　erosion　were　analyzed.　According　to　Fick＇s　second　law　and　the　path　probability　model,　the　unconditional　probability　density　distribution　of　corrosion　rate　at　different　service　periods　was　obtained,　and　then　the　probability　density　distribution　of　resistance　corresponding　to　different　service　periods　was　obtained.　The　three　parameter　Burr　XII　distribution　model　was　used　to　fit　it.　The　Monte　Carlo　method　was　used　to　calculate　the　reliability　probability　of　the　bridge　in　different　service　periods,　and　the　effect　of　the　carbonization　and　chloride　accumulation　on　the　probability　of　corrosion　of　steel　bar　as　well　as　the　resistance　and　the　reliability　of　the　bridge　was　studied.　The　results　show　that　the　resistance　and　reliability　of　the　bridge　gradually　decrease　with　the　increase　of　service　time,　and　the　dispersion　of　resistance　increase　gradually.　The　resistance　and　reliability　of　the　bridge　reduce　when　the　effect　of　carbonization　and　chloride　accumulation　is　considered.　The　effect　of　carbonization　and　chloride　accumulation　on　bridge　reliability　is　mainly　manifested　in　the　later　stage　of　service.　The　influence　of　carbonization　and　chloride　accumulation　should　be　considered　when　evaluating　the　reliability　of　a　bridge　that　has　been　in　service　for　a　long　time.　©　2019,　Editorial　Board　of　Journal　of　Harbin　Institute　of　Technology.　All　right　reserved.