Study On Model Experiment Of The No.1 Bridge By Xinghai Bay, Dalian City

There're huge concrete blocks at earth-anchored suspension bridge to drag the main cable, which is substituted by the end cross beam of self-anchored bridge, so the girder turns from local transferring loads component back to major carrying loads components on the self-anchored bridge, and leads to the "Constructing girder before Erecting Cable" construction method. Different from usual self-anchored bridge, the spacial net cable system lands in multi-transferred cable force, which reflects on the hangers tension course and the completion performance. To make these characteristic clear, the correlation study is carried out by a 1:40 model experiment, and compared the results with FEM calculations. The main conclusions go as follows:(1) The improved "alternative tension " method is taken at the last turn of the tension adjustment job. When the hangers is "capped" and tensioned almost near the completion force, it goes by the last turn work whose target is to make the hangers force more uniformity, just like the design value. For the rigidity of 3#, 5# main cable is weaker than 2# and the force of the hangers below the main cable of 3#, 5# is easily mutual interfered, so while the hangers below the main cable of 3# , 5# are being tensioned , both hangers beside the 5# main cable should be tensioned all the time to maintain the completion force. After that, the hangers left should be tensioned from west to east with the alternative tension method.(2) The reflection to the loads after completion of this bridge presents basically linear.(3) There's no symmetric rigidity of the structure after completion: from the west quarter span to the east quarter span the rigidity of the girder is growing weaker;and as the rigidity of the tower is growing stronger, the weakest rigidity cross section is moving to the west.(4) The laying out error of the unstressed length of the main cable has impact on the structure completion rigidity. The longer of the 1# main cable is, the structure rigidity is stronger;the shorter of the 2# main cable is, the structure rigidity is weaker.