瓮马铁路乌江特大桥设计关键技术研究OA

The newly built Wujiang Super Major Bridge on Weng'an-Zunyi Railway leaps over a deep valley between two mountains.The topography at the bridge site is complex and the bridge design is difficult.This thesis describes the conceptual considerations and structural design of the main bridge first,and then carries out the static and dynamic simulation analysis of the bridge by using the space finite element software.Research conclusions:The stiff skeleton deck-arch bridge with a main span of 337 m has the advantages of large rigidity,small creep and less maintenance work.The main arch is designed with small rise-span ratio,taking into account safety,economy,environmental protection and aesthetics.The arch rib is composed of concrete-filled steel tubular skeletons and the encasing non-shrinage C55 concrete,and the internal forces in different components of the arch are improved by means of casing concretet in layers and segments.The composite girder is consisted of two I cross-section steels and concrete slabs,and the steel girder are connected by bombination of bolting and welding,which is convenient for manufacture,transport and construction.The arch abutment is an expanded foundation with ladder-shaped section,and permanent and temporary measures are used in foundation excavation to reduce construction risk.The numerical analysis shows that the rigidity,strength and stability of the bridge structure can meet the requirements of the code and the safety and riding comfort requirements of the mixed passenger-freight line.It can provide some references for other mountain railway bridge design.