Analysis Of Damage Caused By Longitudinal Prestress And Prevention Measures For Cantilever Casting Concrete Box Girder

The prestressed concrete box girder bridges with its cheap, beautiful, good bendingtorsional performance advantages, are widely used in bridge engineering, after a generalinvestigation for designed and built bridge in our country, most of the bridges have appeareddifferent degree of the disease, which caused great economic losses and adverse social impact,what’s more the ratio of disease caused by prestressed box girder cracking ratio is higher,therefore, this paper was researched on the cast-in-place concrete box girder’s damage whichwas caused by longitudinal prestress and the prevention and control measures.First, this paper introduces the analysis methods by use of Dr Truss bridge calculationsoftware and Refinement of MIDAS FEA calculation software and the box girder damagedetection methods for box girder damage. In the analysis of box girder, the overall calculationuses the truss finite element model method and the local analysis uses the entity’s finiteelement model method. Based on the powerful finite element model analysis for box girder,the theoretical calculation results tend to be more precise. Through the damage identificationin the process of concrete box girder construction, can get the box girder’s internalmechanical response which is the measured values. By comparison with the theoretical valueand measured value, it can be intuitive and clear understanding of the box girder internalmechanical response.Secondly, this paper has studied the longitudinal prestress concrete web damage causesand prevention measures, and made a bridge case analysis. Through the investigation of boxgirder web plate concrete damage results, and the numerical simulation for the developmentof the damage, it can obtain the sensitive parameters and main cause of damage, and putforward web damage prevention and control measures.Then, this paper has studied the longitudinal prestress concrete web damage causes andprevention measures, and combined with a bridge case analysis. After a survey of box girderfloor’s concrete damage form, and a numerical simulation for the design scheme andconstruction process, the writer gets the sensitivity parameters and main cause of injury andputs forward the prevention and control measure for motherboard damage.Finally, according to research results, the Dongwu bridge uses the achievement.In a word, this paper studies the longitudinal prestress concrete box girder damagemechanism, and puts forward prevention measures and suggestions, which can effectivelysolve the problem of suspension pouring concrete box girder damage of typical diseases, to ensure the safety of bridge structure, extend the service life of bridge, reduce the maintenance,repair, reinforcement, has the vital significance.