Static And Dynamic Performance Analysis Of Box-girder Bridge With Corrugated Steel Webs

The prestressed concrete structure occupied the main position in the simply supported beam bridge and continuous girder bridge in China, but the steel-concrete structure is mainly used for long-span suspension bridge, cable-stayed bridge and arch bridge. The box-grider bridge with corrugated steel webs is the new choice for the simply supported beam and continuous beam as a new steel-concrete structure. With the advantage of light self-weight, reasonable structure, excellent seismic performance, energy conservation, environmental protection and beauty, made this form bridge has rapid development in the research and construction in recent years.At present, the studies of box-grider bridge with corrugated steel webs are mainly concentrated in shear, bending, torsion and stability. The model test are always focused on small span bridge such as simply supported beam, but the study is relatively lock in the long span bridge, especially in the dynamic analysis research. The engineering research background is a span of 156 meters of continuous girder bridge with corrugated steel webs in this paper. Calculate and analyze the static performance and the dynamic response under seismic action by finite element model which build by ANSYS and Midas.Under two kinds of limit states conditions, calculate respectively for the box girder bridge with corrugated steel webs and equivalent static PC box girder bridge, and the stress and displacement of two different structures are compared. Research suggests that the bending moment were largely burden by concrete top and bottom flange. The phenomenon of stress concentration has happen in the area of steel vertical connection with concrete. It suggest to improve the quality of construction, ensure the connection reliability.It calculate and analyze the seismic response of the structure by using response spectrum analysis method and time-history analysis method. Vertical seismic action has bigger impact on the structural. The peak value of stress and displacement mainly appeared in the cross section and the steel joint with concrete near zero-block. Compare the two methods, the results are consistent in displacement, stress of the response spectrum method is bigger than the time-history analysis method, but the stress distribution features of two methods are similar. The bridge have better seismic performance.It analyze the influence of the torsional mechanical properties and natural vibration characteristics on the bridge by adjusting the number and thickness of the diaphragm plate. Research suggests that by setting diaphragm plate number and thickness reasonably, the torsional performance of the structure has a larger increase, but less influence on the natural frequencies and mode of vibration.