基于稳定性分析的开口钢箱梁吊装施工参数分析

Analysis of Lifting Construction Parameters of Open Steel Box Girder Based on Stability Analysis

为探讨钢箱-混凝土组合梁桥开口钢箱梁在吊装施工时的稳定性问题,采用有限元软件分析了吊点间距、吊索与钢箱梁平面的夹角等施工参数,钢箱梁宽跨比、高跨比、腹板厚度、横隔板数量等结构参数对吊装过程中开口钢箱梁的稳定性影响。计算结果表明,吊点间距越小或夹角越小,开口钢箱梁更易发生整体失稳,吊点间距越大或夹角越大,开口钢箱梁更易发生局部失稳;较优的夹角为50°,吊点间距为0.8 L;增加横隔板数量以及增大腹板厚度会提高开口钢箱梁的稳定性。

To explore the stability of open steel box girder of steel box-concrete composite beam bridge during hoisting construction,this paper used finite element software to analyze the influence of construction and structural parameters on the stability of open steel box girder during construction,construction parameters include the distance between lifting points,the angle between the sling and the plane of the steel box girder,and structural parameters include width-span ratio,height-span ratio,web thickness,number of diaphragms.The calculation results show that the smaller distance between the lifting points or the smaller angle will make the open steel box girder more prone to overall instability,the greater distance between the lifting points or the greater angle,the open steel box girder will be more prone to local instability.The optimal angle is 50°,and the optimal lifting point spacing is 0.8 L.Increasing the number of diaphragms and the thickness of the web will improve stability of open steel box girder.