大跨径连续刚构-连续梁桥梁体纵向缩短及梁端横向偏位研究

Research on Longitudinal Shortening and Lateral Deflection of Long-Span Continuous Rigid-Structure and Continuous Combination Beam Bridge

对某大跨径连续刚构-连续梁桥梁体出现纵向缩短及梁端横向偏位的原因进行研究分析。按照杆系有限元原理,采用Midas Civil建立模型,并考虑预应力张拉、长期混凝土收缩徐变及成桥后运营期的温度效应等多种影响因素进行数值计算。计算结果表明:混凝土长期收缩、徐变是梁体纵向缩短的主要原因,横向温差效应是梁端发生横向偏位的主要原因。

It has been found that a long span continuous rigid-structure and continuous combination beam bridge has longitudinal shortening and transverse displacement of the beam end in recent years, and the reasons are discussed and analyzed in the article. According to the finite element principle of the rod system, the model is established by using Midas Civil, and several factors such as prestress tensioning, long-term concrete shrinkage and creep and temperature effect of the post-bridge operation period are calculated numerically. The results show that the long-term shrinkage and creep of concrete is the main reason for the longitudinal shortening of the beam, and the transverse temperature difference is the main reason for the transverse deflection of the beam end.