基于悬链线的大跨度悬索桥基准索股调整

目的检验抛物线调索公式的正确性，寻找更为精确的基于悬链线公式的基准索股调整计算方法或计算公式．方法基于基准索股的悬链线解答，提出了调整索长的精确计算方法，该法能自动计入主塔偏位，索股温度等影响。根据悬链线的线形方程，推导了等高、不等高两种情况下的索长与跨中标高的悬链线简化调缆公式，应用于悬索桥的中边跨索股调整．结果对实桥中跨的基准进行调整时，悬链线简化调缆公式和抛物线调缆公式均具有很高的精度，前者精度高于后者；对实桥边跨的基准索股进行调整时，两者均有些误差．结论对于悬索桥中跨的基准索股调整可直接运用悬链线和抛物线简化调缆公式的计算值，而对边跨的基准索股调整时．可将值适当放大．

The Adjustment of Datum Strand Based on Catenary Equation in Long-Span Suspension Bridges

In order to verify correctness of the catenary formulas for strand adjustment, and search a more accurate method or expression, a new precise method of calculating the adjustment length of datum strand is proposed based on the catenary equation. It can reckon with the influence of both temperature and the devia- tion of towers. （ The ratios expressions of the stained length of datum strand in one span to its vertical coordinate at the middle of span are deduced when the two endpoints being at equal elevation or unequal elevation）. The deduced simplified formulas can be used in the datum strand adjustment in suspension bridges construction. An example is introduced to compare the three methods including the two methods mentioned earlier and the method based on the parabola equation. The result shows that when used in the midspan, the catenary adjustment method and the parabola adjustment method will both lead to the exact ratio value, and the results can be used straightly for construction ;but when used in the side-span, the two methods will result in some errors. As a result, when used in construction control, the values should be enlarged.