不同温度下悬索桥锚跨索股的张拉力

Strand Tension in Anchor-Span Suspension Bridge at Different Temperatures

通过简化公式计算和程序计算两种方法研究了温度对边跨索股张拉力、锚跨索股张拉力的影响,并以广州珠江黄埔大桥为例进行算例分析,结果表明:两种方法的计算结果基本接近;散索鞍固定时,温度变化对锚跨张拉力的影响远大于边跨,对边跨索股张拉力的影响系数在-1 kN/℃左右,对锚跨索股张拉力的影响系数达-6～-7 kN/℃;当温度变化超过张拉理想温度范围时,边、锚跨处索股索力差值将大于鞍座提供的最大静摩擦力,具体施工时,须采取一定的防滑措施;散索鞍自由时,温度变化对锚跨索股张拉力影响很小.

Two methods,one is based on the simplified expression and the other is on the calculation program,are proposed to reveal the influence of temperature on the strand tensions in the anchor span and each side span of suspension bridge,with Zhujiang Huangpu Bridge in Guangzhou as an example.It is found that the calculated results obtained from the two methods are approximate to each other,that temperature variation has a greater influence on the tension in anchor span than on that in side span when the saddles are fixed,that the influence coefficient of temperature in side span and anchor span are respectively about-1kN/℃ and-6～-7kN/℃,that the force difference between side span and anchor span may go beyond the maximum friction when the temperature change exceeds the ideal range,so that some countermeasures should be taken to avoid the strand sliding during the construction,and that the influence coefficient of temperature in anchor span is very small when the saddles are free.