鄂东长江公路大桥索塔锚固区节段模型试验研究

以鄂东长江公路大桥索塔锚固区为研究对象,采用1:1足尺模型试验与有限元分析相结合的方法,研究钢锚箱与混凝土组合结构索塔在不同索力状态下的受力特性和混凝土的抗裂性能,模型试验最大荷载为1.6倍设计组合索力.研究结果表明:试验荷栽为1.0倍设计组合索力时,塔壁裂缝位于边跨侧索导管口上方,最大宽度为0.15 mm,小于设计允许裂缝宽度,钢锚箱上测点最大应力为94.6 MPa,个别部位存在应力集中现象,但钢结构整体处于结构弹性范围内;试验荷载为1.6倍设计组合索力时,塔壁最大裂缝宽度扩展至O.27mm,组合结构能继续承载,说明结构有足够的安全度.

Sectional Model Test Study of Cable-to-Pylon Anchorage Zone of Edong Changjiang River Highway Bridge

Taking the cable-to-pylon anchorage zone of Edong Changjiang River Highway Bridge as the research object, the authors investigate the mechanical behavior and concrete cracking performance of the composite steel anchor box and concrete structure pylon under the action of different cable forces, using the combined method of the 1:1 full-scale model test and finite element analysis, in which the maximum load applied in the test is 1. 6 times of the designed cable force combination. The results of the investigation show that when the test load is 1. 0 time of the designed cable force combination, the cracks in the pylon wall appear at the upper part of the cable duct mouths on the side of the side span and the maximum width of a crack is 0. 15 mm that is smaller than the allowable designed width. The maximum stress in the measurement point on the steel anchor box is 94. 6 MPa and the concentrated stress exists only in a few locations in the anchor box, however, the steel structure is integrally still within the elastic range. When the test load is 1. 6 times of the designed cable force combination, the maximum with of the crack propagates to 0. 27 mm, the composite structure of the pylon can continue to carry the load, further showing that the structure has sufficient safety.