曹娥江大桥主桥索塔锚固区节段足尺模型试验方案与空间受力性能研究

Anchorage zone of cable-stayed tower in Caoe River Main Bridge:plan of the full-scale model test and spatial stress analysis

曹娥江大桥主桥拉索锚固区为双钻石型联体桥塔混凝土结构,在环向预应力及较大斜拉索索力的作用下,锚固区的应力分布和传递十分复杂。对该桥索塔锚固区节段的足尺模型制定试验方案,用以研究主塔预应力束的施工工艺以及索塔锚固区的实际应力场,并通过对索塔锚固区节段足尺模型的空间有限元分析,掌握锚固区的空间受力性能。有限元分析结果表明:在使用阶段,环向预应力筋在各个区域可以较好的抵消斜拉索拉力,索塔模型整体受力良好。有限元分析的主要结果对斜拉桥索塔锚固区设计有一定参考作用。

The anchorage zone of Caoe River Main Bridge is made of concrete structure,whose tower shape is like two diamonds conjoined together. The stress distribution and transfer of the anchorage zone become very complex under the circumferential pre-stressed tendon and great diagonal tension. The full-scale model test program of the cable pylon anchorage zone is made to study the construction technology of the pre-stressing tendon and the actual stress field of the anchorage zone. With the help of the finite element simulation analysis of the full-scale model,the structural spatial behavior of the zone is mastered. The result of finite element simulation analysis indicates that: under working condition,circumferential pre-stressed tendons offset the effect of oblique load,so the whole tower model is in well-working state.The results have important guidance to the design of anchorage zone on cable-stayed bridge.