连续刚构桥锚固区局部应力的研究

Investigation on Local Stresses in Anchorage Zone of Continuous Rigid Frame Bridge

为便于箱梁腹板预应力筋及锚具的布置,结合虎跳门连续刚构桥的方案设计,对特征节段模型、子区域模型和试验模型锚下混凝土局部应力分别进行了理论分析、数值计算和试验研究.结果表明:较大的锚下混凝土应力仅限制在很小范围内;在按实桥设计的大吨位预加力作用下,没有导致混凝土主应力过大和失效;锚固区混凝土局部应力的实测值与计算值比较接近.

To arrange the prestressed tendons and anchor devices on the web of box girder conveniently, a theoretical analysis, numerical calculation and model test on local stresses in concrete under anchor devices were performed separately using a typical segmental model, a subrange model and a similar model for the scheme design of Hutiaomen major bridge. The results show that higher concrete stresses occur only in a very small zone under anchor devices, and large prestressing force designed in light of the real bridge does not cause extremely high principal stress and concrete failure. In addition, the measured values of local stresses in concrete in an anchorage zone are comparatively close to their calculated values.