Finite Element Analysis On Precast Prestressed Concrete T Beam

Prestressed concrete T beam was used in a long-term process.With use requirement changing,load changing,aging and damage of natural disasters,durability of a part of the bridge structures degenerate,thus bridge is unable to accomplish the using function.The technology of repair and reinforcement of the bridge structure arises,and main methods are enlarging section method,external prestressing reinforcement method,pasting reinforcement method,increasing auxiliary method,ferruling reinforced concrete method,outsourcing steel plateand so on,among which CFRP strengthening method is one of effective methods.At present,researches of this method are mainly focuse on theoretical analysis and experiments,but the computer finite element simulation is relatively less.Finite element simulation can consider more parameters on basis of ensuring results are right,which have a good supplementary to theoretical analysis and experiments.Through numerical analysis of CFRP board reinforced concrete T beam and some T beam bridges by ABAQUS,a software of finite element simulation,main works are as follows:Respectively Establishing finite element models of precast prestressed concrete T beam under concentrated load,symmetry concentrated load and uniform load,and analyzing calculating the whole force process.The calculatng results show that the bearing capacity improved by increasing concrete strength grade,increasing the thickness of CFRP,increasing the length of CFRP,increasinge the area of CFRP,increasing the depth-span ratio and the width-span ratio.The ultimate bearing capacity linear increases with the increasing concrete strength grade,CFRP thickness,then nonlinear increases with the rest parameters.Establishing calculation models which are suitable for prestressed T beam bridge,and calculate and analyze the whole forces process of.The calculating results show that:in the precast concrete bridge that is consist in some T beams,the deformation difference are small and collaborative force phenomenons are obvious among beams in cases of the load is bigger and close to center;Bridge stiffness increase with increasing bridge panel thickness?decreasing girder spacing,adding the number of diaphragm plate,and changing obviously.But the plate stiffness change is not obvious when diaphragm plate spacing within the scope of 5 m to 10m,and concrete strength within the scope of C35?C55;Bearing capacity of some T girder bridge increase with increasing bridge panel thickness?decreasing girder spacing,adding the number of transverse diaphragm?decreasing diaphragm plate spacing and increasing concrete strength grade of diaphragm plate,and change obviously.Concrete strength grade,depth-span ratio,wide span ratio,height-width ratio of one T beams can not only affect its stiffness and bearing capacity,but also affect other T beam.