Study On Mechanical Properties Of Partially Cable-Stayed Bridge With Corrugated Steel Webs

The composite box-girder bridge with corrugated steel webs is a new type of bridge structure which has been widely applied in domestic in recent years. It was originally often used for continuous beam and continuous rigid frame bridges, and with its ever-expanding applied range and rising requirement of the span, domestic and foreign designers also begin to apply it in larger span bridges such as cable-stayed bridge and partially cable-stayed bridge. In consideration that partially cable-stayed bridge appeared late and its structure itself is relatively new, besides, the application of this bridge type with corrugated steel webs as box girder webs in domestic and overseas is not widespread, it is necessary to conduct a comprehensive research on the mechanical properties of partially cable-stayed bridge with corrugated steel webs. Combined with existing research results, this paper relies on one domestic newly built partially cable-stayed bridge with corrugated steel webs called Zhengzhou to Dengfeng Fast Track Chaoyanggou Reservoir Bridge(hereinafter referred to as "Zhengzhou Chaoyanggou Reservoir Bridge") as engineering background, and research on the shear lag effect and eccentric load effect for partially cable-stayed bridge with corrugated steel webs is conducted through experimental study and finite element analysis, which is helpful to deeply understand the mechanical properties of this structure and apply it more. This paper mainly completes the following work:(1) According to the actual structure of Zhengzhou Chaoyanggou Reservoir Bridge, a plexiglass reduced scale experimental model according to the similitude ratio of 1:20 is established, and experiment research on partially cable-stayed bridge with corrugated steel webs is conducted. The results of experiment and finite element calculated value are compared, thus to verify the validity of the finite element model.(2) Discussing the characteristics of box-girder shear lag effect under different load conditions, and analyzing the longitudinal distribution law of box-girder shear lag coefficient.(3) The effect degree of width-span ratio, web thickness and diaphragm type on the shear lag effect of partially cable-stayed bridge with corrugated steel webs is researched. It gives the calculation formula of box-girder cross section maximum shear lag coefficient under different load conditions with width-span ratio as variable, and obtains corresponding calculation formula of effective distribution width coefficient.(4) Conducting comprehensive analysis on the eccentric load effect of partially cable-stayed bridge with corrugated steel webs. The longitudinal distribution law of the eccentric load coefficient is researched, and the effect degree of width-span ratio, diaphragm type and diaphragm interval on the eccentric load effect is analysed.(5) Conducting the bridge accomplished load test on Zhengzhou Chaoyanggou Reservoir Bridge, thus verifying the accuracy of model experiment and finite element analysis results.