以某斜交空心板连续梁桥为工程背景,进行实桥拼宽后的应变和位移监测以及非线性有限元分析,研究混凝土收缩徐变对斜交空心板梁桥拼宽结构受力性能的影响.研究结果表明:利用ABAQUS计算得到的收缩徐变对斜交空心板梁桥的结构受力性能的影响,与实测结果较为吻合;斜交空心板拼宽桥梁中,新桥收缩徐变会导致中跨跨中梁底纵横向应变显著增加,收缩徐变对拼宽斜交桥位移的影响,以横向位移最大,纵向位移次之,竖向位移最小.
The strain and displacement of the widened skew slab bridges before and after widening were monitored to reveal the mechanical behaviors.Based on the site monitoring and finite element analysis,the study was concentrated on the influence of the shrinkage and creep of concrete on the mechanics behaviors of the widened skew slabs bridge.Some conclusions were extracted from the testing and nonlinear analysis and listed as follows:(1) the calculation results are close to the testing results as considering the impact of the reinforcement.Shrinkage and creep calculation program using ABAQUS is suitable to calculate the shrinkage of concrete creep.(2) For the widen project of skewed hollow slab bridge,the shrinkage and creep of new bridge will significantly increasing the strain in the bottom of middle section of in midspan,shrinkage and creep will cause the displacements of skewed bridge in all three directions,and the transverse displacement is biggest,as longitudinal displacement is smaller and the vertical displacement is smallest.