| Popis: |
Rotational construction for bridges attracts much attention of people because it is featured by its low initial cost, fast and easy operation and minimum traffic interruption. Nowadays, rotational bridges have been mostly built by the level rotation method of the ring combining with ball joints at home and abroad, which is more safe and easy to control the closed precision, but the large rotating friction restrict the promotion of the rotational weight and span. The author takes flat hinge supported by single point as the rotating bearing type, using embedded four fluorine board, controlling wheel construction precision strictly. In that case, Suifen He cabl-stayed bridge, weigh up to to 14000t, has been successfully complished rotational construction with the help of continuous jack. The built bridge axis deviation is limited within 3mm, and maximum deck height deviation is only 12mm. It is proved that rotational construction of flat hinge joints supported by single point can efficiently solve the colsed accuracy which is difficult to control and problems of heavy rotating traction, as long as the installation precision and the sliding performance can be controlled. |
