斜拉索顺桥向风阻系数的试验研究

Experimental Study on Drag Coefficients of Stay-cables Corresponding to Wind Direction along the Bridge Central Line

采用风洞试验的方法研究了4种不同表面的斜拉索(包括1种光索、2种螺旋线索和1种凹坑索)在不同倾角下的顺桥向阻力系数.试验结果表明:凹坑索和2mm螺旋线索的阻力系数相差不大,均可应用于斜拉桥的设计当中.根据试验结果给出了形式上比较简单的用于计算斜拉索不同倾角下阻力系数值的拟合公式.分析表明,此拟合公式和试验结果拟合较好且偏于安全.

With the increase of the span of cable-stayed bridges, flat box girders that are approximately streamline and thick cable systems are inclined to be used. The proportion of wind load that acts on cables is increasing, even exceeds that acting on main beams. So it is necessary to investigate into the drag coefficients of cables through the method of wind tunnel test. In order to provide the wind loads acting on cables for cable-stayed bridge design, this paper investigates into drag coefficients of stay-cables with four different surface configurations under different inclinations corresponding to wind direction along the bridge central line respectively through the method of wind tunnel tests. According to the test results, simple fitting formulas are given which can be used to calculate drag coefficients under different inclinations.