膨胀土桩基施工对紧邻管道受力变形的影响

Influence of Expansive Soil Pile Foundation Construction on Forced Deformation of Adjacent Pipelines

针对我国膨胀土地区中桩基紧邻管道施工广泛存在的情况,文章以云南保山绕城高速胡家坡大桥为工程背景,建立桩基、土体和管道(石油、燃气)的整体三维数值模型,考虑上部结构自重和施工荷载,分析膨胀土桩基施工对邻近管道受力变形的影响。结果表明:桩基施工诱使管道发生竖向及水平变形,累计变形为0.9mm;管道水平应力及竖向应力均处于较低水平,桩基施工对管道受力影响较小,管道结构处于安全状态;桩顶轴向压力对邻近管道受力及变形的影响可以忽略不计。

In view of the widespread existence of pile foundation construction adjacent to pipelines in expansive soil area in China,with Hujiapo Bridge of Yunnan Baoshan Ring Expressway as engineering background,this article established an overall 3D numerical model of pile foundation,soil body and pipeline（oil and gas）.Considering the self weight of upper structure and the construction load, it analyzed the influence of expansive soil pile foundation construction on the forced deformation of adjacent pipelines.The results showed that the pile foundation construction induces the vertical and horizontal deformation of the pipeline,and the cumulative deformation is 0. 9mm;the horizontal stress and vertical stress of the pipeline are both at a relatively low level ;the pile foundation construction has little influence on the pipeline stress ,and the pipeline structure is in a safe state,The effect of axial pressure at pile top on the force and deformation of adjacent pipelines is negligible.