悬索桥主缆丝股锚固力的计算方法探讨

Study of Calculation Methods for Anchorage Force of Main Cable Wire Strands of Suspension Bridge

悬索桥主缆丝股的锚固力的计算是悬索桥施工控制的一项重要内容。悬索桥主缆锚固力的计算有几种方法,各种方法有其优缺点和适用范围。对于滚轴式散索鞍应采用锚跨与边跨的丝股张力在滑动斜面上的投影合力为0为条件计算锚跨张力;对摇轴式散索鞍,应采用边跨和锚跨在散索鞍切点处的张力对摇轴中心合力矩为0为条件计算锚固力。实际的施工控制中,对这2种散索鞍,可分别以上述的总合力或合力矩为条件,所有丝股设定一个完全相等的锚固力,该固定力近似等于按2种精确方法计算的各丝股锚固力的平均值。

It is an important part of suspension bridge construction control to calculate the anchorage force of the main cable wire strands. There are several methods available for calculating the anchorage force, each being of its advantages, disadvantages and applicable ranges. For roller splay saddle, the tension of anchorage span should be calculated under condition that the resultant forces of the wire strand tension of both side and anchorage spans projecting from the sliding incline plane are equal to zero. For rockshaft splay saddle, the anchorage force should be calculated under condition that the tension of both side and anchor spans at the tangent point of the saddle in relation to the resultant moment at the the rockshaft center is equal to zero. In the actual construction control, for the two kinds of saddles, the calculation may be made under condition that the above-mentioned total resultant forces or resultant moment are respectively used, and all wire strands may be assumed to have a completely equal anchorage force that is approximately equal to the mean values of the anchorage force of each wire strand according to the two kinds of precise calculation methods as described herewith.