Research Into Construction Control Technology Of PC Rigid Frame Bridges With Long Span

With the rapid transit development of China's highway and railway,more long span bridges were needed to span great rivers and bays,PC continuous rigid frame bridge emerged as the times require and was developed fleetly in recent years. The PC rigid frame bridge can meet with the carrying capacity of long span bridge. This kind of structure is fit for the comfortable steer with no other expansion joints except for those at the two ends. It characterized the wholeness of structure,good astigmatic ability and load-bearing ability,construction rapidness,bright and pithiness bridge style,easy to maintain and convenient for segmental construction using the cantilever technique,so rigid frame bridge have taken an increasingly great proportion in bridges constructed and those under construction at city and county.The rigid frame bridge adopts the economical and reasonable segmental construction technique (including cantilever installation and cantilever mold). This construction method results in the complex change of the internal forces and displacements in the bridge. The bridge construction control is essential measure and step to ensure the quality and safety in the procedure of the bridge construction. In this essay the technique of the structure calculation and error adjustment measures used in bridge construction prefigurative deviation control was researched based on the construction control and monitor project of Wuhan Caidian Han river bridge.The first part of the paper gives a brief historical retrospect to the development of PC rigid frame bridges,and a detailed account of the information about their structure design and construction technique,and an introduction to the recent research at domestic and abroad,and an exposition of the necessity and significance of the study in this paper:First,to analyze the influence of the factors come from the construction procedure on the bridge structure internal forces and line form,for the accumulation of experiences to guide" construction control in the same type of bridge.Second,to search for reasonable bridge construction supervision and control means in order to consummate the construction monitor and control technique usedin big span PC rigid frame bridges.The second part of the paper offers an account of the project concerned,that is,the construction control method of Wuhan Caidian Han river bridge.After that,the paper makes a relatively profound study analysis of the structure calculation and error adjust forecast technique used in PC rigid frame bridges construction monitor and control,and comprehensive analyzes of the influence factors in building the bridges,based on the engineering practice. Then on the basis of calculating result from the prefigurative deviation control structure calculation," rational data forecast processing about error adjust in prefigurative deviation control was made by the prefigurative theory of BP Neural Network and corresponding program and software MATLAB6.1.At last via the data comparison with the practical survey data draw a conclusion:It is feasible for the construction prefigurative deviation control and error adjust used in PC rigid frame bridges to use the calculation model and program brought forward in this paper.