广州沙湾大桥索鞍区模型试验

Model Test for Stay Cable Saddle Zone of Shawan Bridge in Guangzhou

为检验广州沙湾大桥索鞍区受力是否满足规范要求,对该桥斜拉索鞍座处桥塔节段进行模型试验研究。制作最大设计索力鞍座处桥塔节段足尺模型,依次进行节段受力性能试验和斜拉索抗滑移性能试验,并采用ANSYS建立相应桥塔节段有限元模型进行理论计算。试验结果与有限元计算结果表明:试验过程中,桥塔节段混凝土表面没有出现裂纹,内部未出现开裂,桥塔节段混凝土拉、压应力均满足设计和规范要求;分丝管应力水平较低且变形较小,其对应力的分散作用显著;施工阶段斜拉索不会在鞍座内产生明显的滑移;成桥阶段,斜拉索抗滑锚固装置完全能满足设计抗滑能力的安全系数的要求。

To check if the force conditions of the stay cable saddle zone of the Shawan Bridge in Guangzhou could meet the relevant requirements in the codes,the model test study of a pylon segment in the saddle zone was carried out.The full-scale model for the pylon segment that could sustain maximum designed cable force was prepared and the force conditions of the segment and the slip resistance of the cables were tested in succession.The finite element model for the corresponding segment was built by the ANSYS and the theoretic calculation was made as well.The results of the test and finite element calculation show that in the process of the test,no cracking appears either in the surface of or in the concrete of the pylon segment,the tensile stress and compressive stress of the concrete can meet the requirements in the design and in the codes,the stress level and deformation of the saddle pipes is low and the action of stress dispersing of the pipes is significant.At the construction stage,the cables will not apparently slip in the saddle and at the completion stage,the slip resistant anchor device of the cables can completely satisfy the requirement of safety factors of the designed slip resistance capacity.