摘要
厦门市金尚路跨线桥第一联为5×30m预应力混凝土连续曲线梁桥,根据该桥提升改造要求,左、右幅最高顶升分别为952.717mm、969.145mm。该桥采用PLC控制液压同步系统,按刚体转动的要求同比例旋转顶升梁体,并设置纵横向限位装置。为保证该桥旋转顶升施工顺利,采用有限元软件建立全桥及局部有限元模型,计算梁体强迫位移和局部应力,给出强迫位移和应力增量安全预警值;对梁体的强迫位移和混凝土拉应力增量进行监测,利用全站仪和偏移量监测装置监控梁体竖向线形及梁体横向偏移量。施工控制及模态试验结果表明,梁体未发生明显横向偏位和纵向滑移;顶升过程中个别行程横向强迫位移、拉应力增量超出预警值(在下一行程中调偏纠正),纵向强迫位移未超限,梁体被安全顶升到位;顶升后桥梁具有良好的静、动力性能。
The first continuous unit of the Overpass on the Jinshang Road in Xiamen is a 5×30m prestressed concrete continuous curved beam bridge.According to the requirements of the rehabilitation construction,the maximum jack-up amounts for the left and right decks are 952.717 mm and 969.145 mm,respectively.The PLC hydraulic lift control system was used to rotate and jack up the beams by the same proportion in accordance with the requirements of rigid structure rotation,and both the longitudinal and transverse restraints were added.To ensure the smooth progress of the rotation and jack-up construction of the bridge,the finite element software was used to establish the overall and local finite element models of the bridge,to calculate the enforced displacement and local stress of the beams,so as to provide the safety alarming values for enforced displacement and stress increment and monitor the enforced displacement and the tensile stress increment of the concrete.The total station and displacement monitoring devices were used to monitor and control the vertical alignment and transverse displacement of the beams.The results of the construction control and modal test demonstrate that no distinct transverse displacement and longitudinal sliding was found on the beams,the transverse enforced displacement and tensile stress increment exceeded the alarming values in some stages of the jacking process,which could be rectified in the next stage.The longitudinal enforced displacement was not over the limit,and the beams were safely jacked up into position.The bridge shows sound static and dynamic performance after the jack-up rehabilitation.
出处
《世界桥梁》
北大核心
2016年第2期87-91,共5页
World Bridges
基金
国家自然科学基金项目(51368032)
关键词
曲线梁桥
旋转顶升
限位装置
强迫位移
应力
预警值
有限元法
桥梁改造
施工控制
curved beam bridge
rotation and jack-up
restraint device
enforced displacement
stress
alarming value
finite element method
bridge rehabilitation
construction control
