隧道开挖对有接头地埋管线影响的工程评价方法

隧道开挖产生的土体位移对地埋管线的影响不可避免,不仅会引起管线接头的相对旋转,甚至会造成损坏和泄漏。目前对有接头管线响应的研究方法较为复杂,大多基于数值分析方法,接头力学性质的影响考虑不够全面,已有的设计图表工程应用欠缺。结合连续管线的理论分析,考虑地层位移沉降曲线、管段刚度及接头刚度等影响因素,建立了有接头管线的工程评价方法,以分析隧道开挖对有接头地埋管线的影响。运用该方法对实际工程案例进行分析,并将计算结果与数值分析结果对比,验证本文方法的可靠性。本工程评价方法可以为实际管线工程安全预评估起到一定的作用。

Evaluation method for effect of tunneling on underground jointed pipelines

The soil settlement produced by tunneling has an inevitable effect on the neighbouring buried pipelines, which may cause joint rotation, leakage and even damage in serious cases. At present, the research methods for the response of jointed pipelines are complicated. Most of them require complex numerical calculation, in which the research on the influence of joint properties is not comprehensive enough. The obtained design charts only contain a few simple engineering conditions, thus resulting in the lack of practicality. In this study, the Winkler foundation model with an elastic foundation modulus formula under passive load is employed to study the influence of joint location and joint stiffness on pipeline response. Considering the theory of continuous pipelines, a simplified method is established to evaluate the influence of tunneling on the buried jointed pipelines in terms of the greenfield conditions and mechanical properties of joint and pipe section. Finally, the method for jointed pipelines is used to analyze some actual projects. The comparisons reveal that the proposed method can provide a preliminary risk assessment for engineering design.