大跨度体外预应力钢梁施工技术研究OA

A double-cable solid-web prestressed steel beam was used for the roof structural beam of a conference center auditorium.Using finite element software,three tensioning methods including overhead one-time tensioning,ground one-time tensioning and phased tensioning were compared.A sensitivity analysis was carried out to investigate the effects of unsynchronized tensioning that may occur during the tensioning process.In addition,the strength and deformation of the prestressed steel beam in the whole process of the construction stage and under the subsequent construction loads were analyzed and compared with the construction monitoring results.The results show that when the prestress tension deviation is within 5%,its effects on the strength,deformation,and stability of the steel beam can be effectively controlled.The finite element analysis results show good agreement with the monitoring data in terms of structural strength and deformation,with variation trends consistent with actual construction conditions.The structural performance indices of the structure are within the specification requirements during the whole construction process and under the subsequent construction loads.