This paper presents a method to optimize the hoop prestressing tendons in the cable-pylon anchorage zones of the cable-stayed bridge,aiming to prevent cracking and improve stress distribution in the anchorage zones.The method combines the 3D numerical simulation and genetic algorithm,by which,the former is conducted to identify the concrete areas requiring optimization,taking the prestressing coefficients as the design variables to build up mathematical optimization model,while the latter is used to constantly iterate and optimize the design variables,so as to achieve an optimal stress condition in the cable-pylon anchorage zones.For a cable-stayed bridge of the Liyang-Ningde Expressway,the presented method was used to optimize the hoop prestressing tendons in the cable-pylon anchorage zones,complemented with full-scale model test,and the optimization was modified by measured prestress loss.It is shown that the hoop prestressing tendons are able to provide the pylon walls in the anchorage zone with a compressive prestress of 6 to 8 MPa,to effectively improve the tensile performance of the pylon walls.The full-scale model test saw a prestress loss of 10％,and the tested stresses agreed well with the theoretical values,proving the accuracy of numerical simulation.A prestressing tendons plan was determined in accordance with the analyses,which allowed the maximum tensile stresses in the cable-pylon anchorage zones to reduce by 27.1％and effectively enhance the stress distribution in the anchorage zone.
关键词
斜拉桥/索塔锚固区/环向预应力/优化方法/遗传算法/数值仿真/足尺模型试验
Key words
cable-stayed bridge/cable-pylon anchorage zone/hoop prestressing tendons/optimization method/genetic algorithm/numerical simulation/full-scale model test
维普
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