The main bridge of Liujiaxia Bridge is a 536 m single span stiffening truss girder suspension bridge with double cable planes .Each cable is made of 44 strands consisting of 127 no .φ5 .2 mm high-strength galvanized steel wires .The porosity at the cable bands is designed as 18% , and 20% between the cable bands .Each cable band has an upper and a lower semi-circular halves which are butt-joined and fixed to the main cables through high-strength bolts ,and the joints are filled with rubber waterproof strips .The slippage of cable bands is a major factor affecting the nor-mal utilization of the suspension bridge .To see whether the anti-slippage performance of the cable bands can meet design requirements ,after the main cables were erected into place and compacted , the braking cable bands ,testing cable bands and thrust jacks were installed simultaneously on the main cable .The jacks were used to simulate the slipping force of cable bands .Pushing test was carried out for the most unfavorable cable band selected by calculation ,so as to determine the anti-slippage friction coefficient of cable bands and the porosity inside and outside cable bands .The re-sults of the test indicate that the measured anti-slippage friction coefficient of cable bands is 0 .213 , greater than the designed value of 0 .15 ,meeting the design requirements .The measured porosity inside and outside the cable bands are 17 .6% and 18 .4% ,respectively ,which also meet the design requirements .%刘家峡大桥主桥为单跨536 m 的桁式加劲梁双索面悬索桥，单根主缆采用44股127根φ5．2 mm 镀锌高强钢丝，设计空隙率在索夹处取18％，在索夹外取20％，主缆索夹由2个半圆形铸钢结构通过高强度螺栓上下对接紧箍在主缆上，接缝处嵌填橡胶防水条。索夹的抗滑移性能是影响悬索桥主缆正常使用的一个主要因素。为了解该桥索夹抗滑移性能是否满足设计要求，在大桥主缆架设完紧缆后，在主缆上同时安装制动索夹、试验索夹以及推力千斤顶，利用千斤顶模拟索夹下滑力，对计算确定的最不利索夹进行顶推试验，测试索夹抗滑移摩阻系数和索夹内、外部空隙率。试验结果表明：实测索夹抗滑移摩阻系数为0．213，大于设计要求的0．15，满足设计要求；实测索夹内、外部空隙率分别为17．6％、18．4％，满足设计要求。
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