Suspension Bridge Cable Construction Monitoring

In view of the drawbacks of the existed methods, a new method for calculating long-span suspension bridges is presented. In this method, the fact that the second deadload of bridge is supported by both the main cable and the stiffening-girder is taken into consideration, the suspended-cable mechanics is applied, the cable between focus load is regarded as catenary, the alteration method is used which is based on the condition of force equilibrium and condition of deformation compatibility. Applying the method, the construction control calculation of bearing rope and main cable is introduced, including the unstressed length and elevation of bearing ropes of catwalk, the unstressed length of main cable, the pre- displacement of saddle, the fixed position for erecting cable band etc. The temperature is of key factor in control calculation, so the paper researches the effect of temperature specially. Using the control method that this paper introduced, the main cable and catwalk of Yichang Changjiang Highway Bridge is controlled very well. The erection-precision is up to the standard of our country completely, which proves that this method is more precise.