散粒土管涌临界水力梯度的研究  

Study on Critical Hydraulic Gradient for Piping in Granular Soils

作　　者：王霜 陈建生[2] 钟启明[3] 周鹏[1] WANG Shuang1,2 ,CHEN Jian-sheng2 ,ZHONG Qi-minga ,ZHOU Peng1(1. MCC Huatian Engineering ＆ Technology Corporation, Nanjing 210019, China; 2. College of Civil and Transportation Engineering, Hohai University, Nanjing 210098, China; 3. Nanjing Hydraulic Research Institute, Nanjing 210029, Chin)

机构地区：[1]中冶华天南京工程技术有限公司,江苏南京210019 [2]河海大学土木与交通学院,江苏南京210098 [3]南京水利科学研究院,江苏南京210029

出　　处：《水电能源科学》2018年第9期114-117,共4页Water Resources and Power

基　　金：国家自然科学基金项目(51779153)

摘　　要：针对传统管涌判别方法的局限性问题,通过对渗流场中土体孔隙通道内的可动颗粒进行力的平衡分析,得到管涌发生的临界水力梯度表达式。在进行颗粒受力分析时,根据流体力学中相对运动原理,通过静水中运动物体之间的相互作用力,进而推求出受周围颗粒影响的水流拖曳力大小。该判别方法除了考虑周围颗粒对起动颗粒水流拖曳力的影响,同时还考虑了颗粒半径、孔隙率、土体组成、土颗粒所处的位置及孔隙水流方向等各方面因素的影响,最后比较该方法计算的理论值与既有管涌试验结果,两者吻合度较好。研究成果可为散粒土管涌临界水力梯度的确定提供理论依据。Considering the limitation of the traditional piping distinguishing method, the critical hydraulic gradient for the particle moving was deduced by the static equilibrium of the particles in soil pores. The forces on the soil particles was analyzed, and the drag force of the flow was calculated by the interaction force between moving particles in static water according to the principle of relative motion. This piping distinguishing method considered the influence of surrounding soil particles on the drag force of the flow. Furthermore, the particle radius, soil porosity, soil composition, position of the moving particle and flow direction were also considered in this method. Comparison of the theoretical value of critical hydraulic gradient and the experimental value was conducted, the results show that the goodness of fit is high. This research will provide a theoretical basis for determining the critical hydraulic gradient for piping in granular soils.

关 键 词：散粒土 管涌 判别方法 临界水力梯度 水流拖曳力 

分 类 号：TV223.4[水利工程—水工结构工程]