三跨连续梁桥内力调整顶升施工仿真分析与控制研究

摘要

某三跨连续梁桥由于施工造成连续梁内力分布不合理，通过三维实体有限元仿真分析模拟在中间支座处施加向上变化的强迫位移，可以改变连续梁的内力分布，使之更为合理。根据该原理，对中间支座位置，采用千斤顶顶升梁体，使梁体向上产生对应于合理梁内力的位移值，然后在支座上加垫钢板，即可完成三跨连续梁的内力调整。通过仿真分析，确定加垫钢板厚度及安全状况下最大顶升量，并根据连续梁桥顶升时的受力和变形特点提出加垫钢板顶升施工控制的方法及原则。%A three-span continuous bridge has unreasonable distribution of internal force for defective construction. With three-dimensional entity finite element analysis simulation, imposed displacement upward changing is given at the central support, which can alter the distribution of internal force of the continuous bridge and make it more reasonable. According to the planning, a jack is applied to hoist the beam, making the beam move upward and gener-ate the displacement value reasonable to its internal force, and then a steel plate is placed at the support, thus, the internal force adjustment of a three-span continuous bridge is accomplished. Through simulation analysis, the steel plate thickness and the maximum safe jacking volume can be determined, and the methods and principles of jacking construction control of the steel plate are presented in accordance with the stress and deformation features of the continuous bridge when jacked.