无黏性土管涌的临界流速  

Critical hydraulic velocity for piping in non-cohesive soils

作　　者：赵正信[1] 陈建生[1] 陈亮[1] 叶合欣[2] 

机构地区：[1]河海大学岩土工程研究所,江苏南京210098 [2]河海大学科学研究院,江苏南京210098

出　　处：《水利水电科技进展》2008年第2期13-15,共3页Advances in Science and Technology of Water Resources

基　　金：国家自然科学基金(50579017)

摘　　要：根据多孔介质中的变截面管模型,分析单个颗粒在孔隙通道中的受力情况,建立力的平衡方程,从而推导出管涌发生时的水流临界流速公式。结合试验对该公式进行了验证,当作用于水流的拖曳力与静水压力的作用大于阻碍其运动的作用时,认为可动颗粒开始起动。算例分析表明,运用临界流速公式能够准确地预测土体的管涌破坏。Using a variable-section tube model through porous media, forces acting on a single particle in the pore channel were analyzed, and a critical hydraulic velocity formula for piping occurring in non-cohesive soft was deduced from the force balance equation. The formula was verified by experiments under the assumption that removable particles will be initiated when the actions of tractive stress on water flow and hydrostatic pressure exceed the retarding forces. A case study shows that failure type can be precisely estimated by use of the critical hydraulic velocity formula.

关 键 词：无黏性土 管涌 临界流速 颗粒级配 孔隙率 

分 类 号：TV223.4[水利工程—水工结构工程]