自然科学版 英文版
自然科学版 英文版
自然科学版 英文版
自然科学版 英文版
英文版编委
自然科学版 英文版
英文版首届青年编委

您目前所在的位置:首页 - 期刊简介 - 详细页面

中南大学学报(自然科学版)

Journal of Central South University

第48卷    第5期    总第273期    2017年5月

[PDF全文下载]    [Flash在线阅读]

    

文章编号:1672-7207(2017)05-1367-09
堆积碎石土细观孔隙空间特征对其渗透特性的定量影响
董辉1, 2,罗潇1,李智飞1

(1. 湘潭大学 土木工程与力学学院,湖南 湘潭,411105;
2. 成都理工大学 地质灾害防治与地质环境保护国家重点实验室,四川 成都,610059
)

摘 要: 堆积碎石土作为滑体物质往往因其细观结构差异对雨水入渗产生影响。基于CT扫描宏细观孔隙特征,以自制渗透仪研究级配(坡顶区域、坡腰区域、坡脚区域)、干密度(1.65,1.75和1.85 g/cm3)、含石率(30%~70%)等条件下碎石土的渗透规律。采用“最小累积差值”阈值选取方法对CT图像进行阈值分割,提取图像碎石和空隙形态,利用灰关联分析法定量分析各因素(碎石面积比率、空隙面积比率等)对渗透系数的影响。研究结果表明:空隙面积比率是影响渗透系数的主要因素;考虑含石率作为主要影响条件时,随着含石率的减少(从70%减至30%),空隙面积变异系数、空隙周长变异系数及空隙分形维数均呈现先增加后减少的趋势,存在1个含石率阈值使其碎石土的渗透系数最小;根据空隙面积比率(x)与碎石面积比率(y),获得渗透系数(k)拟合函数,其为运用图像处理技术估算滑坡坡表碎石土渗透系数提供简明有效的新途径。

 

关键词: 碎石土;滑坡;渗透;CT图像;灰关联分析

Quantitative influence of meso-porosity space features of aggregate gravel soil on its permeability characteristics
DONG Hui1, 2, LUO Xiao1, LI Zhifei1

1. College of Civil Engineering and Mechanics, Xiangtan University, Xiangtan 411105, China;
2. State Key Laboratory of Geohazard Prevention and Geoenvironment Protection,
Chengdu University of Technology, Chengdu 610059, China

Abstract:Given different internal mesoscopic structures, aggregate gravel soil which are considered to be the landslide materials tend to influence on rainwater infiltration. Based on macro and micro-pore characteristics observed via CT scan, the experimental research employed homemade permeameter to explore permeation law of the gravelly soil with different graduations (slop crest, mid slope, the toe of slope), different dry densities (1.65, 1.75 and 1.85 g/cm3) and different stone contents (30%-70%). Meanwhile, further study utilized the minimum cumulative scores threshold selection method to extract images gravel and void morphology by segmenting CT image. The gray relational analysis method was applied to analyze the effects of different factors (stone area ratio, void area ratio) on permeability coefficient. The results show that surface void ratio is the most significant factor that affects the permeability coefficient. Simultaneously, with the reduction of containing stone rate (70%-30%), the void area variation coefficient, viod perimeter variation coefficient, void fractal dimension firstly decrease and then increase. When the containing stone rate decreases to something, the permeability coefficient reaches the minimum. It is assumed that surface void ratio(x) and surface stone ratio(y), fit the permeability coefficient(k) formula, which provides a concise and effective new way to use image processing techniques to estimate gravel soil permeability on the landslide slope.

 

Key words: gravel soil; landslide; permeability; CT image; grey relational analysis

中南大学学报(自然科学版)
  ISSN 1672-7207
CN 43-1426/N
ZDXZAC
中南大学学报(英文版)
  ISSN 2095-2899
CN 43-1516/TB
JCSTFT
版权所有:《中南大学学报(自然科学版、英文版)》编辑部
地 址:湖南省长沙市中南大学 邮编: 410083
电 话: 0731-88879765(中) 88836963(英) 传真: 0731-88877727
电子邮箱:zngdxb@csu.edu.cn 湘ICP备09001153号