中文摘要：

箱梁桥拓宽设计时，新旧桥基础差异沉降引起的刚接翼缘板内力是新板设计和旧板验算的前提。为研究该项内力的简化算法，以某连续箱梁桥拓宽工程为例，基于变形协调原理分析了新桥基础不均匀沉降全部工况下刚接翼缘板的变形，按上拱和下挠2种情况分别比较得到刚接翼缘板横向两侧相对位移的最大值，并偏安全地将其简化。以简化值为荷载，结合梁模式，针对桥梁纵向不同位置分别提出了沉降引起的刚接翼缘板内力的简化算法。最后将荷载简化值和简化算法的内力与三维实体有限元法的计算结果进行对比，验证了简化算法的可行性和计算精度。

英文摘要：

The internal h）rce of rigidly-connected flange plate between new and old box girders due to foundation differential settlement is the premise of new plate design and old plate checking when widening box girder bridge. In order to study the simplified algorithm of the internal force, the deformation of rigidly- connected flange plate under uneven settlement conditions of new bridge foundation is analyzed by principle of deformation coordination based on a 3-span continuous box girder bridge widening project. The relative displacement extremums of both lateral sides of rigidly-connected flange plate are obtained according to up and down deflections respectively through comparing all conditions and it is securely simplified. Then, using the simplified value as load and combining beam mode, the simplified algorithms for internal forces of rigidly- connected flange plate at different longitudinal locations are proposed respectively. Finally, by comparing the simplified load value and the internal force calculated by simplified algorithm with the calculation result of 3 D solid finite element method, the feasibility and the accuracy of simplified algorithm are verified.