The problems like cracking of the girder in the mid-span and the ever-increasing vertical deflection appear during the long term usage of the long-span continuous rigid-flame bridge. Post-tension tendon with re- serve...The problems like cracking of the girder in the mid-span and the ever-increasing vertical deflection appear during the long term usage of the long-span continuous rigid-flame bridge. Post-tension tendon with re- served duct can increase the pre-stress of the main beam effectively, and decrease the long term span deflection in order to improve the performance of the girder. At the same time, the proper tension position is very crucial to optimise the stress distribution of the bridge and control the deflection increase. Combining with practical en- gineering, the authors analyze the influence of different positions of post-tension tendon （ including top-, web- and bottom plate tendons） on the stress and deflection of the main beam, and find out the optimal position of post tendon.展开更多
It is helpful to improve the seismic design theory of long-span continuous bridges for studying the seismic performance of each cantilever construction state.Taking the Bridge 1 in the north of Changbai-Mountain inter...It is helpful to improve the seismic design theory of long-span continuous bridges for studying the seismic performance of each cantilever construction state.Taking the Bridge 1 in the north of Changbai-Mountain international tourism resort as an example,the authors studied it in shutdown phase and the cantilever construction process,established the simulation model by using Midas / civil,and analyzed time-history of each construction stage for the bridge.The study shows that long-span bridge cantilever construction in northeastern China can be divided into two-year tasks for construction(suspending in winter).It is needed to think about seismic stability of the cantilever position in shut-down phase of winter.The effect of longitudinal vibration is the most disadvantageous influence to bridge,and its calculation results can provide reference for seismic design of similar bridges in the future.展开更多
A timely and accurate damage identification for bridge structures is essential to prevent sudden failures/collapses and other catastrophic accidents.Based on response surface model(RSM)updating and element modal strai...A timely and accurate damage identification for bridge structures is essential to prevent sudden failures/collapses and other catastrophic accidents.Based on response surface model(RSM)updating and element modal strain energy(EMSE)damage index,this paper proposes a novel damage identification method for girder bridge structures.The effectiveness of the proposed damage identification method is investigated using experiments on four simply supported steel beams.With Xiabaishi Bridge,a prestressed continuous rigid frame bridge with large span,as the engineering background,the proposed damage identification method is validated by using numerical simulation to generate different bearing damage scenarios.Finally,the efficiency of the method is justified by considering its application to identifying cracking damage for a real continuous beam bridge called Xinyihe Bridge.It is concluded that the EMSE damage index is sensitive to the cracking damage and the bearing damage.The locations and levels of multiple cracking damages and bearing damages can be also identified.The results illuminate a great potential of the proposed method in identifying damages of real bridge structures.展开更多
文摘The problems like cracking of the girder in the mid-span and the ever-increasing vertical deflection appear during the long term usage of the long-span continuous rigid-flame bridge. Post-tension tendon with re- served duct can increase the pre-stress of the main beam effectively, and decrease the long term span deflection in order to improve the performance of the girder. At the same time, the proper tension position is very crucial to optimise the stress distribution of the bridge and control the deflection increase. Combining with practical en- gineering, the authors analyze the influence of different positions of post-tension tendon （ including top-, web- and bottom plate tendons） on the stress and deflection of the main beam, and find out the optimal position of post tendon.
文摘It is helpful to improve the seismic design theory of long-span continuous bridges for studying the seismic performance of each cantilever construction state.Taking the Bridge 1 in the north of Changbai-Mountain international tourism resort as an example,the authors studied it in shutdown phase and the cantilever construction process,established the simulation model by using Midas / civil,and analyzed time-history of each construction stage for the bridge.The study shows that long-span bridge cantilever construction in northeastern China can be divided into two-year tasks for construction(suspending in winter).It is needed to think about seismic stability of the cantilever position in shut-down phase of winter.The effect of longitudinal vibration is the most disadvantageous influence to bridge,and its calculation results can provide reference for seismic design of similar bridges in the future.
基金The National Natural Science Foundation of China(Grant Nos.51178101 and 51378112)The University Graduate Student Scientific Research Innovation Plan of Jiangsu Province(Grant No.CXZZ13_0109)China Scholarship Council under Program for Graduate Student Overseas Study Scholarship
文摘A timely and accurate damage identification for bridge structures is essential to prevent sudden failures/collapses and other catastrophic accidents.Based on response surface model(RSM)updating and element modal strain energy(EMSE)damage index,this paper proposes a novel damage identification method for girder bridge structures.The effectiveness of the proposed damage identification method is investigated using experiments on four simply supported steel beams.With Xiabaishi Bridge,a prestressed continuous rigid frame bridge with large span,as the engineering background,the proposed damage identification method is validated by using numerical simulation to generate different bearing damage scenarios.Finally,the efficiency of the method is justified by considering its application to identifying cracking damage for a real continuous beam bridge called Xinyihe Bridge.It is concluded that the EMSE damage index is sensitive to the cracking damage and the bearing damage.The locations and levels of multiple cracking damages and bearing damages can be also identified.The results illuminate a great potential of the proposed method in identifying damages of real bridge structures.
