Reinforcement Design for Anchorage Beams of Externally Prestressed Bridges Based on Tensile Stress Region Method

Abstract:

Based on well-regulated two dimension tensile stress regions at the back of anchorage structures of prestressed concrete bridges,a new method on reinforcement design named “tensile stress region method” is advanced for the lack of reinforcement theories.The blocks can be divided into several tensile stress region slices,then the web reinforcement is raised up to bear the tensile stress orthonormal value for each,and the notion “tensile stress region slice depth” is advanced to control the longitudinal length of reinforcement.An example of external prestressed anchorage reinforcement is analyzed by means of tensile stress region method,thus a finite element model is built up.In addition,the influences of transverse,vertical prestressing are also taken into consideration.The results show that the reinforcement amount is affected obviously by the transverse,vertical prestressing at the anchorages when the tensile stress region method is used,this method can set steel bars according to the stress state,and more exact reinforcement results can be obtained.