摘要
开展高水力梯度作用下破碎岩体非达西渗流试验,揭示试样孔隙率和级配对非达西渗流特性和临界水力梯度的影响机制;以试样孔隙率和Talbot级配系数为基础建立Forchheimer定律非达西渗流系数、线性项系数和非线性项系数计算模型;以达西定律为基础,对压力梯度-渗流量曲线分段处理提出非达西等效渗透系数,并构建非达西等效渗流模型。结果表明试验数据高度服从Forchheimer定律,试样临界水力梯度范围为125~183,并且由于水流惯性力的影响,试样孔隙率越大、粗颗粒占比越多,临界水力梯度值越小;Forchheimer定律非达西渗流系数、线性项系数和非线性项系数与试样孔隙率和Talbot级配系数之间呈负指数及减幂函数关系;非达西等效渗透性系数与水力梯度之间呈负指数关系,并且取值受试样孔隙结构影响;构建的非达西等效渗流模型与Forchheimer定律吻合度较高,并且具有计算参数少、能适应达西渗流与非达西渗流之间的相互转换和共存的优势。
Non-Darcy seepage experiments of broken rock mass were carried out under high hydraulic gradient.The influence mechanism of non-Darcy flow characteristic and critical hydraulic gradient was revealed with different porosity and gradation of rock mass sample.Considering the influence of the porosity and Talbot gradation coefficient,the calculation models of the non-Darcy flow coefficient,linear and non-linear term coefficients of Forchheimer's law were established.By piecewise analyzing the relation curve of pressure gradient and flow rate with Darcy's law,the non-Darcy equivalent hydraulic conductivity was proposed,and the non-Darcy equivalent seepage model was established.The results show that the experimental data were highly compliant with Forchheimer's law.The critical hydraulic gradient was changed from 125 to 183.Because the influence of inertia force,the critical hydraulic gradient was reduced with increased porosity and the number of coarse particle of rock mass sample.The non-Darcy flow coefficient,linear and non-linear term coefficients of Forchheimer's law have negative exponential with porosity and reduced power relationship with Talbot gradation coefficient.The non-Darcy equivalent hydraulic conductivity have negative exponential relationship with hydraulic gradient and decided by the pore structure of rock mass sample.The established non-Darcy equivalent seepage model was highly agreement with Forchheimer's law.The established model possessed fewer calculation parameters and could adapt to the coexistence and interconversion between Darcy flow and non-Darcy flow.
作者
许增光
曹成
柴军瑞
李炎隆
李琳娜
XU Zengguang;CAO Cheng;CHAI Junrui;LI Yanlong;LI Linna(State Key Laboratory of Eco-hydraulics in Northwest Arid Region,Xi'an University of Technology,Xi'an,Shaanxi 710048,China)
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2023年第S02期4099-4108,共10页
Chinese Journal of Rock Mechanics and Engineering
基金
国家自然科学基金资助项目(52209167,52179143)
陕西省科技创新团队(2022TD-01)
关键词
岩石力学
破碎岩体
渗流试验
非达西渗流
压力梯度
渗流模型
rock mechanics
broken rock mass
seepage experiment
non-Darcy seepage
hydraulic gradient
seepage model
作者简介
许增光(1982-),男,2012年于上海交通大学环境科学专业获博士学位,现任教授,主要从事水利工程渗流分析与控制方面的教学与研究工作。E-mail:xuzengguang@xaut.edu.cn;通讯作者:曹成(1992-),男,现任讲师。E-mail:caocheng_xaut@163.com
