独塔双索面预应力混凝土斜拉桥施工监控

Construction Monitoring of Prestressed Concrete Cable-stayed Bridge with Single Tower and Double Cable Planes

某独塔双索面预应力混凝土斜拉桥为跨径组合2×120 m、预应力混凝土双边箱主梁、H形主塔结构,采用节段悬臂现浇和部分支架现浇相结合的施工方法。为确保成桥后主梁线形与结构内力满足设计要求并保证施工安全,采用Midas/Civil软件建立有限元模型进行正装计算分析,按照“线形控制为主、索力控制为辅”的控制原则进行桥梁施工监控。结果表明:成桥线形整体上接近理论线形,误差控制在24 mm以内,成桥索力误差控制在5%以内,结构线形、索力监控均满足设计预期。

Combined construction of segmental cantilever cast-in-situ and partial support cast-in-situ was used in a prestressed concrete cable-stayed bridge with single tower,double cable planes and a span combination of 2×120 m.The bridge was composed of double side box girder and H-shaped tower.In order to ensure the alignment of the main beam and the internal force of the structure meet the design requirements and ensure the construction safety.Midas/Civil software was used to establish a finite element model for regular-order installation calculation.And analysis and the bridge construction monitoring was carried out according to the control principle that the alignment is the key control focus along with cable forces monitoring.The construction monitoring results showed that the alignment meets the expected target requirements,the error is controlled within 24 mm,the error of the cable force is controlled within 5%,the structural alignment and cable force monitoring meet the design expectations.