非饱和黄土埋地管道渗流潜蚀水毁及其辨识

Seepage Damage and Identification for Buried Pipeline System in Unsaturated Loess

管周土作为埋地管道系统的重要组成部分,渗流机械侵蚀对其破坏是埋地管道系统地下水毁灾害的主要形式之一.在非饱和黄土潜蚀特征及分类基础上,分析了非饱和黄土渗流侵蚀特征及其水动力条件,给出了非饱和土渗透系数计算参数的工程求值方法;依据渗流侵蚀临界启动流速理论及计算公式,给出了非饱和土渗流侵蚀发生的临界判据和计算参数的求值方法.分析了非饱和黄土埋地管道渗流水毁的致灾机理以及其地面辨识标志;结合上述讨论,提出了符合现场实际的非饱和黄土埋地管道渗流水毁灾害风险工程缓解措施.

The soil around the pipeline is an important part of the buried pipeline system,and the damage caused by the mechanical erosion of the seepage for it is one of the main forms of the groundwater damages in this system.On the basis of analyzing and summarizing the characteristics and the hydrodynamic conditions for the seepage erosion,the classification and applied calculating methods of some parameters in the unsaturated loess are given.According to the theory of the critical condition on the sediment-moving incipient velocity and the formulas for the erosion of seepage,the critical criterion of the seepage damage in the unsaturated soil is given.The disaster mechanism of the seepage damage for the buried pipeline system in the unsaturated loess is analyzed,and the ground identification marks of these damages are also given.Finally,based to reduce the above discussion,the applicable mitigation measures on the risk of the seepage damage for the buried pipeline system in the unsaturated loess are proposed.