某空心板桥碳纤维加固效果有限元分析

Finite Element Analysis of Carbon Fiber Reinforcement Effect on a Hollow Slab Bridge

以宝成铁路某立交通道上的空心板桥为例,采用Midas FEA建立空心板桥三维有限元模型,考虑混凝土与钢筋的材料非线性,分析了空心板桥采用碳纤维加固前后结构的受力性能,研究表明:采用碳纤维加固空心板桥可以在一定程度上降低跨中截面上缘的压应力最大值、跨中截面附近的挠度最大值以及裂缝宽度最大值,有效减少裂缝的分布区域;随着二次荷载的增大,加固后的空心板梁桥的受力性能指标的下降幅度逐渐增加,碳纤维的加固效果越来越明显;空心板梁桥加固过程中增大碳纤维的粘贴厚度可以在一定程度上提高加固效果。

Taking the hollow slab bridge on an interchange channel of Baoji-Chengdu Railway as an example,the three-dimensional finite element model of hollow slab bridge was established by Midas FEA.Considering the material nonlinearity of concrete and steel bar,the force of the structure before and after carbon fiber reinforcement was analyzed.The research showed that the hollow slab bridge reinforced by carbon fiber could reduce the compressive stress maximum at the upper edge of the mid-section,the deflection maximum near the mid-section and the crack width maximum to reduce the distribution of cracks.With the increase of the secondary load,the decrease of the mechanical performance index of the reinforced hollow slab girder bridge was gradually increased,and the reinforcement effect of carbon fiber was more and more obvious.Increasing the thickness of the carbon fiber during the reinforcement of the hollow slab girder bridge could improve the reinforcement effect to some extent.