Chloride　attack　and　carbonization　are　the　main　factors　which　affect　the　durability　of　concrete　structures,　and　the　respective　theoretical　models　are　systematically　established.　However,　the　quantitative　analysis　and　models　about　the　coupling　effect　of　chloride　attack　and　carbonization　are　less,　so　the　precision　and　level　of　durability　analysis　of　reinforced　concrete　are　restricted.　Diffusion-limited　aggregation　(DLA)　model　can　finely　simulate　the　process　of　gas　diffusion　and　condensation　with　randomness　and　fractal　characteristics,　which　is　suitable　for　revealing　the　durability　evolution　process　of　the　chloride　attack,　carbonization,　and　the　coupling　action　in　concrete.　Based　on　the　principle　of　DLA,　considering　the　factors　such　as　diffusion　depth,　concrete　properties,　and　exposure　conditions　which　influence　the　characteristics　of　chloride　diffusion　and　carbonization,　as　well　as　the　coupling　effect,　an　integrated　DLA　model　is　established.　The　concentration　of　carbon　dioxide　and　chloride　at　any　time　and　any　location　can　be　obtained　and　dynamically　displayed　based　on　the　DLA　model.　The　performance　predict　method　for　concrete　and　steel　bars　considering　fatigue　effect　is　presented　based　on　DLA,　according　to　the　demand　for　bridge　durability　analysis.　Numerical　examples　show　that　the　method　can　dynamically　and　intensively　simulate　the　durability　evolution　process　of　reinforced　concrete　bridge.