Zhang Z.-J.,South China University of Technology |
Wang R.-H.,South China University of Technology |
Zhen X.-X.,South China University of Technology |
Liu X.-H.,Guangdong Expressway Co. |
Han X.-C.,China Railway Major Bridge Nanjing Bridge and Tunnel Diagnosis and Remedial Co.
Bridge Construction | Year: 2016
To evaluate the applicability and measurement precision of the 5 methods like the string wire gauge method, magnetic flux method, frequency spectrum method, load cell method and jack method for measurement of the tension of the parallel steel strand stay cables, the vibration signals of the stay cables of Tongling Changjiang River Rail-cum-Road Bridge [a continuous steel truss girder cable-stayed bridge with span arrangement (90+240+630+240+90) m] in the construction process were collected and studied. The measured data of the tension of the stay cables of the bridge under the different load cases were statistically analyzed and the measurements under the different load cases and by the different methods were compared. The results show that the vibration of the sheaths of the parallel steel strand stay cables can represent the vibration of the stay cables themselves and this gives the basis for measurement of the tension of the stay cables, using the frequency spectrum method. The deviations among the measurements of the frequency spectrum method, jack method and load cell method are in the range of 5% and can basically satisfy the construction control requirements while the measurements of the string wire gauge method and magnetic flux method can be used to check the measurements of the other methods. © 2016, Journal Press, China Railway Bridge Science. All right reserved.
Yi Y.-K.,Xiamen University of Technology |
Yi Y.-K.,Fujian Xiazhang Bridge Co. |
Yan H.-Z.,China Railway Major Bridge Nanjing Bridge and Tunnel Diagnosis and Remedial Co. |
Zhao K.-P.,The 5th Engineering Co. |
Yue Q.,China Railway Major Bridge Nanjing Bridge and Tunnel Diagnosis and Remedial Co.
Bridge Construction | Year: 2013
The north main bridge of the Xiazhang Sea-Crossing Bridge is a steel box girder cable-stayed bridge with double pylons and double cable planes. The main girder of the bridge was erected by the cantilever assembling method and the central span was closed by the technique of cutting and pushing. Before the span was closed, the closure gap was continuously observed and the closure gap width-temperature curves were fitted. In the light of the predicted width of the closure gap, the material for the closure block was laid off and also at the temporary fixity of a pylon and the girder, the girder was pushed towards one side and/or withdrawn a little amount. Practice proves that the technique of the cutting and pushing closure applied to the bridge not only ensures the closure block to be smoothly lifted into the closure gap and but also achieves the ideal width of the welding seams. With the technique, the reliability of the closure is improved and the structural safety risk is decreased.