T he Nanxiang Bridge crossing Fenghua River is a three‐span continuous concrete rigid‐frame bridge with span arrangement of(80+130+80) m .The bridge has two separated decks and V‐shaped piers .The inclined legs of the V‐shaped piers adopt the two‐cell single box pres‐tressed reinforced concrete box structure .To ensure the operation safety of the bridge and investi‐gate into the actual ultimate load bearing capacity of the V‐shaped piers in service condition ,the fi‐nite element method was used to establish the three‐dimentional solid non‐linear models of the V‐shaped piers for the purpose of doing quantitative analysis of the limit state of load bearing capaci‐ty ,and the ultimate load bearing capacity of the V‐shaped piers represented by the allowed live load overload coefficient K under the limit state of normal operation .And the K was in turn modi‐fied in accordance with the field monitoring data .The results of the analysis indicate that the al‐low ed K is about 9 in the limit state of cross section load bearing capacity of V‐shaped piers and the failure mode belongs to large eccentric loading failure .Under the limit state of normal service con‐dition ,the allowed K is about 6 ,governed by the maximum compressive stress in the edge of the cross section .Under the restriction of reinforcement stress and crack width of the V‐shaped piers , the allowed K is about 6 .To use the measured stress of the V‐shaped piers in the completed bridge state to replace the theoretical values in the related condition ,the allowed K is about 4 .9 after modification .T he actual load bearing capacity of V‐shaped piers of the bridge under the operation condition is higher .%奉化江南翔桥为（80＋130＋80） m双幅三跨V形墩混凝土连续刚构桥，V形墩斜腿采用单箱双室预应力钢筋混凝土箱形结构。为确保该桥通行安全，了解V形墩在运营状态下的实际极限承载力，采用有限元法建立V形墩三维实体非线性模型，定量分析承载能力极限状态及正常使用极限状态下，以允许活载超载系数 K为表征的V形墩极限承载力，并结合现场监测数据，对 K值进行修正。结果表明：V形墩在截面承载能力极限状态下的允许 K值约为9，破坏形态为大偏压破坏；在正常使用极限状态下的允许 K值约为6，由截面边缘最大压应力控制；在V形墩的钢筋应力及裂缝宽度限制条件下的允许 K值约为6；以V形墩实测的成桥应力代替相应状态下的理论值，修正后的允许 K值约为4．9，该桥V形墩在运营状态下的实际极限承载力较高。
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