The Improved Structure And Construction Key Technology Research Of The Extradosed Cable-stayed Bridge Rhombic Hanging Basket System

With the progress of science and technology, the scale of Road-Bridge construction has been expanding. Extradosed cable-stayed bridge has made a rapid development with its own economic superiority, and from the beginning of 1960 s, it slowly spread around the world. The construction of the main cantilever in extradosed cable-stayed bridge is crucial which determines the quality and safety of the whole bridge. Cantilever construction is divided into cantilever casting method and cantilever erection method, now mostly adopts the cantilever casting construction.Cantilever casting method is cast-in-place with hanging basket, after this period of the concrete cured and stretches prestressed, the hanging basket moves again then uses for the next segment.This paper revolves around Xinyang harbor bridge construction equipment rhombic hanging basket for a modifying and researching, then describes the improved rhombic hanging basket construction key technologies. Because of short construction period, insufficient supply of raw materials and shortage of funds, Construction unit decided to use the original Dongbao river bridge rhombic hanging basket for construction. But for the main girder of Xinyang harbor bridge is wide and its heavy weight, so in order to meet the needs of the original rhombic Xinyang harbor bridge hanging basket the structure should be improved. After the improvement, then the improved rhombic hanging basket is applied to the construction of the main girder.This paper first introduces the general situation of Xinyang harbor bridge project,and the construction scheme of the project are carefully designed. On the basis of this finds out the two representative box girder segment, by using the finite element software and the detailed calculation to analyze the stress and displacement of the original rhombic hanging basket system, according to the two kinds of analysis results indicates that the original rhombic hanging basket system can not meet the construction requirements of the main girder of Xinyang harbor bridge. Therefore, in order to ensure the rhombic hanging basket economical and safety construction, the corresponding improved design has been conducted such as improve the strength,rigidity and stability of rhombic basket structure. To check the improved hanging basket and prove it can be used for the construction. This progress provides effectivetechnical support and reference for the smooth construction of main girder in Xinyang harbor bridge.Through comprehensive, detailed analysis and careful implementation, the project has achieved the goal of advanced technology, reasonable economy and simple construction. The results obtained can provide useful reference for the design and construction of similar engineering rhombic shaped hanging basket.