Study On Reinforcement Scheme And Scheme Parameters Of Hollow Masonry Arch Bridge Strengthened By Hoop Method

In China,there are a lot of existing bridges built in 70s-80 s of last century,based on the design and construction norms of that time.The design of the traffic is on the low level and the construction technology is not very good enought.With the rapid development of society and economy,many kinds of heavy vehicles are constantly appearing,and the load of highway bridges is more and more heavy so that many bridges are unsafe now.In order to save funds and reduce the im Pact on traffic,many local goverment would like not by taking the method of building a new bridge but by the maintenance and reinforcement to improve its load-carrying capability.In this paper,the origin of the masonry arch bridge,the present situation,disease and reinforcement methods at home and abroad are expounded,and by studying a masonry arch bridge in Liangshan state a,combining with the test data of the arch bridge,the causes of the existing disease,the technical evaluation of the structure,the reinforcement scheme,the checking of the section strength of the main arch ring and the construction are studied and computed.The following work are completed:(1)The common diseases and causes of existed masonry arch bridge are analyzed and regulated.The common methods,the newest methods of strengthening the masonry arch bridge and the applicability of each method are discussed.(2)Taking a bridge in Liangshan state as a practical case,the technical condition of the bridge is evaluated according to the current specification.Then,the internal force analysis of the bridge is made with the finite element method.(3)Considering a variety of factors to deter Mine the use of hoop method to strengthen the bridge,three kinds of hoop reinforcement schemes are designed,the reinforcement parameters of stress,axial force and deflection with different schemes are calculated and analyzed according to different thick Ness of brace reinforcement schemes,the best reinforcement scheme and relevant parameters are obtained,and the strength checking of positive section is carried out according to the relevant specifications.(4)Further discussion and research on the material are carried out.The order of maintenance and reinforcement and the key points in construction technology of Masonry arch bridge reinforcement and maintenance are discussed.(5)The analysis results show that the reinforcement thickness is not bigger and better,but it has a best value for its own characteristics.