天津滨海新区西外环盐池段桥梁耐久性设计

A Design of Bridge Durability of West Out-ring Salt Pond Section in Binhai New Area,Tianjin

天津滨海新区盐场分布较广，西外环的部分桥梁工程（桩号K32＋337-K32＋882）位于塘沽盐场的盐池内。根据详勘报告的腐蚀性评价结果，该场地地表水对钢筋混凝土的结晶类腐蚀等级为严重腐蚀、结晶分解类复合腐蚀等级为严重腐蚀。气候上天津属于寒冷地区，会产生冻融腐蚀作用，故需要对桩基、承台、立柱等采取特殊防护措施。通过原材料、结构设计、防腐涂装、外加剂等途径进行耐久性设计，保证桥梁在设计基准期内满足使用要求。

There are salt ponds distributed widely in Binhai New Area,Tianjin and partial bridge project(Stake Mark K32+337~K32+882) of west out-ring is located in salt pond of Tanggu Salt Field.According to corrosiveness evaluation results of detailed survey report,speaking of the field surface water effecting on reinforced concrete,both corrosion rank of crystallization class and compound corrosion rank of crystallization decomposing class are serious corrosion.Tianjin is belonging to cold region climatically,which will result to freezing,thawing & corrosion.And special protective measures shall be adopted to pile foundation,bearing platform and stand column.Through durability design on raw material,structure design,anticorrosive coating and admixture,the bridge can be guaranteed to meet the service requirements during design reference period.