摘要
为解决定量评估干缩裂隙优势流的难题,基于双孔隙域入渗理论,将开裂土体分为裂隙两侧基质域、裂隙底部基质域与裂隙域三部分,结合Green-Ampt入渗模型,提出了一种考虑干缩裂隙动态变化的优势流入渗模型,并基于该模型探讨了降雨强度、裂隙初始面积率及裂隙深度对土体两域积水时间、优势流入渗量及入渗深度的影响规律。结果表明:干缩裂隙产生的优势流入渗量占总降水量的73.4%~91.4%,入渗深度为裂隙深度的3.1~7.2倍;降雨强度增大将缩短土体基质域积水时间,增大优势流入渗深度;降雨过程中干缩裂隙面积率减小使优势流入渗量减小;裂隙初始面积率增大使两侧基质域入渗量减小,优势流入渗量增大但入渗深度减小;裂隙深度增大使裂隙域积水时间延后,优势流入渗深度增大;模型计算结果与干缩裂隙实际入渗规律相符,同时避免了为裂隙域赋水力学参数带来的误差与不便。
To address the problem of quantitative evaluation of the preferential flow model under the desiccation cracks,based on the double pore domain infiltration theory,this paper proposes a new preferential flow model considering the dynamic changes of desiccation cracks with the combination of Green-Ampt infiltration model.In the proposed model,the cracked soil is separated into matrix domains besides the cracks(L-matrix domain),under the cracks(B-matrix domain)and crack domain.Then,the effects of rainfall intensity,initial crack area ratio,and crack depth on the water ponding time,infiltration amount and depth of preferential flow are simulated and discussed.The results show that infiltration amount of preferential flow produced by desiccation cracks occupies 73.4% to 91.4% of the total precipitation.Its ultimate infiltration depth during rainfall is 3.1 to 7.2 times deeper than the crack depth.With the increase of rainfall intensity,the water ponding time of matrix domain decreases and the infiltration depth of preferential flow increases.During rainfall,the decreased crack area ratio leads to the decrease of infiltration amount of preferential flow.Moreover,it is found that with the increase of initial crack area ratio,the infiltration amount of the L-matrix domain decreases and the preferential flow infiltration increases,whereas its infiltration depth decreases.The increased crack depth mainly delays the water ponding time of the crack domain and increase the infiltration depth of preferential flow.In conclusion,the simulated results are consistent with the practical infiltration process within the desiccation cracks,and it also avoids errors and inconvenience caused by the defining hydraulic property of cracks.
作者
程实
陈瑾
罗易
CHENG Shi;CHEN Jin;LUO Yi(Department of Engineering Management,Hubei University of Economics,Wuhan 430074,China;Collaborative Innovation Center for Emissions Trading system Co-constructed by the Province and Ministry,Hubei University of Economics,Wuhan 430074,China;Hubei Provincial Geological Experiment Test Center,Wuhan 430074,China;Faculty of Engineering,China University of Geoscience,Wuhan 430074,China)
出处
《河海大学学报（自然科学版）》
CAS
CSCD
北大核心
2024年第1期37-45,62,共10页
Journal of Hohai University(Natural Sciences)
基金
国家自然科学基金面上项目(42177166)
湖北省地质局科研项目(KJ2023-42)
安徽省2018年度交通运输科技进步计划项目(2018030)
安徽交通控股集团交通科技攻关项目(JKKJ-2017-20)。
