G-M法在小半径曲线箱形梁桥应力分析中的应用研究

Study of Application of G-M Method to Stress Analysis of Sharp Radius Curved Box Girder Bridge

为解决将箱梁比拟成正交同性板时,其横向抗弯刚度Dy、综合抗扭刚度H与实际出入较大的难题,选择箱梁桥跨结构比拟法的难点Dy(横向抗弯刚度)的确定作为突破口,通过空腹框架比拟导出等效Dy的普遍公式,再代入通过构造异性板理论导出的以Dx、Dy函数关系表示的H(综合抗扭刚度)公式。对比拟正交异性板进行理论分析,并通过荷载试验进行验证。结果表明:采用该方法所得的结果和采用有限元法所得的结果符合较好,计算精度较高。该方法可以应用于其它小半径曲线桥梁的应力分析。

When a box girder is analogized as the orthogonal isotropic plate in the calculation of internal force of the girder,the values of lateral bending stiffness Dy and integrated torsional stiffness H thereof differ greatly from the values of actual situations.To resolve the problem of the difference,the general formula of equivalent Dy is derived by the hollow frame analogy and is substituted into the H formula expressed by the functional relation of Dx（longitudinal bending stiffness） and Dy derived according to the structural orthotropic plate theory.Then,the analogized orthotropic plate is theoretically analyzed and is verified by the load testing on a sharp radius continuous curved girder bridge.The results obtained by the method mentioned above are in good agreement with those obtained by the finite element method,the calculation accuracy is high and the method can be also applied to the stress analysis of other types of sharp radius curved bridges.