| PC box girder with corrugated steel web is a new type of steel-prestressed concrete composite structure,which is used widely because of its many advantages.However, due to such an unique folding shape of web, the modulus of shear stiffness should be discounted basing on the original modulus of steel,while the shear almost entirely is borned by the web. As a result, the resulting shear deformation will be larger,and its influence on the deflection will be greater than the past ordinary girder. So this dissertation bases on the science technology project of traffic construction in ShanDong(2005Y017) and the project of traffic tcchnology in HuNan(200706),to research the influence of web's shear deformation on the deflection of prestressed concrete box girders with corrugated steel webs.Deflection control is the most important target during bridge design and construction, so the research on deflection of corrugated web beams has great significance.There is a brief description about the composite girder's tectonic characteristic. Sum up the current varieties of methods about calculating the deflection of composite beams with corrugated steel webs considering shear deformation meanwhile. Among them, Li Hongjiang, Ye JianShu's method is the most simple and practical. And through analyzing some continuous beams with corrugated steel web, we may know this formula not only can apply to simply supported beam, but also to the continuous beam.Through changing the boundary conditions and load conditions of a 1:4 ratable experimental beams basing on a PC box girder with corrugated steel web locating in a highway from NanNing(LuoChuan) to BaiSe, the comparison,between experimental measurements, theoretical value(considering and not considering shearing deformation) and ANSYS finite element value, found that the deflection is less affected by the shear deformation in the symmetrical loads,and the real girder's deformation can be much more accurately simulated by using the elementary beam theory. While in offset loading, the deformation will be larger than the one in symmetric load, and the results of the elementary beam theory will be smaller than the actual value.At this moment, must consider the shearing deformation's influence on the composite beam must be considered. Use the software ANSYS 10.0 to model the experimental beam to research the deflection of experimental beam with corrugated steel web,by changing parameters of the beam and comparing the deflection of the middle of the span.The theoretical analysis intimates that the angle of corrugated web,the length of web's traight section and web's thickNess have little effects on box-girder's deflection.On the contrary, the high-span ratio, diaphragm settings, and the ratio of bending stiffness to shear stiffness have greater impacts. The angle of corrugated web and the length of web's traight section have little effects on box-girder's deflection caused by the shear deformation;but web's thickNess,the ratio of depth to span and the ratio of width to height have obvious effects.Lihong Jiang and Ye Jian-shu's formula is extended to composite beams under horizontal loads to caculate the transverse deformation. Much more, experimental beam is analyzed by using ANSYS 10.0 to test the theories'correctness. The results show that the web has little impact on the lateral deformation of composite beam. Use ANSYS to analyse the continuous girder bridge in HeiNan under horizontal loads and different boundary conditions, and the deformation value is compared with the one of concrete continuous girder bridge.The results show that although the bending stiffness of box girder with corrugated steel web is reduced, but the lateral deformation of girder is not very large compared with the reinforced concrete bridges. And the lateral deflection has met the requirements of specification.
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