鞍座边界的应力带桥计算方法

为了准确分析应力带桥中应力带的受力情况，提出了鞍座支承应力带的计算方法。首先建立应力带在均布荷载作用下的弯矩平衡微分方程，再以应力带在鞍座分离点处挠度约为零、曲率半径为鞍座半径的边界条件来确定微分方程一般解的待定系数，最后根据几何协调关系反算鞍座的支承长度，通过迭代进行求解。为验证该方法的正确性和实用性，将该方法的计算结果与有限元模拟计算结果和铰支边界计算式的结果进行比较。结果表明：该方法的计算公式正确，能高效地找到应力带在鞍座上的分离点，比铰支边界计算式的准确度更高，更适合在实际工程中应用。

Calculation Method of Stress Ribbon Bridges with Saddle Boundary

In order to accurately analyze the condition of stress ribbon in the stress ribbon bridge, a method for calculating the stress ribbon supported by saddle is proposed. First, the bending moment equilibrium differential equation of stress ribbon under uniformly distributed load is established. Then, the undetermined coefficient of the general solution of the differential equation is determined by the boundary conditions that the deflection of the stress ribbon is about zero and the radius of curvature is the radius of the saddle at separation point of saddle. Finally, the supporting length of the saddle is calculated backwards according to the geometric coordination relationship and solved by iteration. To verify the correctness and practicality of the method, the result of this method is compared with the results of the finite element simulation calculation and the hinged boundary calculation formula. The result shows the calculating formula of this method is correct, can efficiently find the separation point of stress ribbon on the saddle, and is more accurate than the hinged boundary calculation formula, which is more suitable for application in practical projects.