Yan Z.-H.,China Railway Sanyuan Survey and Design Group Co. |
Ma L.-Z.,Beijing Qitai Shock Control Science and Technology Development Co. |
Chen Y.-Q.,Beijing Qitai Shock Control Science and Technology Development Co.
Bridge Construction | Year: 2014
The speed lock-up devices have been applied for the first time to the long span continuous girder bridge on Tianjin-Qianhuangdao Passenger Dedicated Railway spanning Ramps of Beijing-Shenyang Expressway. The maximum lock-up force, maximum stroke, the lock-up displacement and lock-up speed of a device are respectively 5000 kN, ±100 mm, 8 mm and 0.25 mm/s. To understand the seismic capacity of the devices, the applying of the devices to the seismic mitigation design of the bridge was studied from aspect of the design parameter selection and seismic mitigation effect analysis. The software MIDAS Civil was used to set up the finite element model for the whole bridge, 5 seismic waves were respectively input into the model, the seismic responses of the bridge structure before and after the lock-up devices were applied were compared. The displacement of the pier tops, relative displacement of the piers and girder and the shear forces, bending moment and vertical forces in the pier footings were analyzed. The results of the analysis show that the lock-up devices can significantly reduce the displacement and seismic forces of the fixed bearing piers of the continuous girder bridge. Under the action of the seismic load, the devices can redistribute the forces of the continuous girder and increase the stability of the structure. Presently, the Tianjin-Shenyang Passenger Dedicated Railway is open to traffic and the lock-up devices on the bridge on the railway have worked quite well.
Zhang L.,China Railway Sanyuan Survey and Design Group Co. |
Yang X.-R.,China Railway Sanyuan Survey and Design Group Co. |
Dou J.-J.,China Railway Sanyuan Survey and Design Group Co. |
Quan W.,China Railway Sanyuan Survey and Design Group Co.
Bridge Construction | Year: 2013
The main bridge of the Huhehaote-Zhungeer Railway Huanghe River Bridge is a prestressed concrete hybrid bridge of rigid frame and continuous girder with span arrangement (98+5×168+98) m. The main girder of the bridge is the C55 concrete single-cell single-box girder of variable section and is arranged with the three-way prestressing system and pre-reserved with the tensioning components for external prestressing strands inside the girder. The main piers are the hollow piers of round-end sections (the two intermediate piers are rigidly fixed with the main girder) and are supported on the frictional pile foundations. To accommodate the large temperature expansion amount of the bridge, the large movement expansion joints and sliding bearings were developed and the software MIDAS Civil was used to carry out the static and dynamic analysis of the bridge. The results of the analysis indicated that the rigidity and strength of the bridge at both the construction and operation stages could meet the relevant requirements in the codes and the bridge had good seismic resistance. The bridge was constructed by the cantilever casting method and the closure sequence of the main girder was that the side spans were closed first and the central span was late.