关于地下水论文范文资料 与地下水浅埋深条件下给水度和水位降深关系有关论文参考文献

《地下水浅埋深条件下给水度和水位降深关系》：这是一篇与地下水论文范文相关的免费优秀学术论文范文资料,为你的论文写作提供参考。

摘 要：本文研究地下水浅埋深条件下,水位降深为0-40cm、0-55cm、0-70cm、0-85cm、0-100cm时给水度的变化规律.利用室内风积砂的排水实验获得实测给水度,分析实测给水度和经验公式计算的给水度和水位降深的关系.结果表明,当水位降深小于毛细上升高度时,给水度较小,并随着水位降深的增加而增大.当水位埋深大于毛细上升高度时,给水度由毛细上升高度段及毛细上升高度以上段组成.毛细上升高度段,给水度随着水位降深的增加而增大,给水度较小.而毛细上升高度以上段,给水度较大,并随着水位降深的增加趋于定值.雷志栋公式计算的给水度和实测给水度最相近.而Nachabe和Duke公式在进气值高度上计算的给水度都比实测给水度大.这些成果为浅埋深情况下地下水位波动的准确估计提供依据.

关键词：给水度排水试验毛细上升高度

The Relation between Specific Yield and Depth to Water Table under Shallow Water Table Conditions

Xiaoli Wang1Donghui Cheng1Xiaoying Qiao1

（1. College of Environmental Sciences and Engineering, Chang′an University, Xi′an 710054, China）

Abstract:The paper analyzes the change of specific yield when depth to water table in 0-40cm、0-55cm、0-70cm、0-85cm、0-100cm under shallow water table through the drainage experiment to determine the changes of gravity specific yield from the soil surface to a different depth to water table. And also analyzes the changes of the measured specific yield with the empirical formula calculated by the specific yield in different depth. The analysis results show that, When the depth to water table less than the height of the capillary fringe above the water table,specific yield is smaller, and the specific yield increases with the increase of the buried depth. With the increase of drawdown, when the water depth is greater than the height of capillary fringe, this section water supply is divided into two parts, the capillary rise height of segment and capillary height of the above paragraph. The specific yield increases with the increase of the buried depth in the height of the capillary fringe. And capillary rise high above section, specific yield is larger. With the increase of the buried depth, the specific yield is constant. Lei Zhidong specific yield equation calculation of water degrees with measured values of the specific yield.But in the soil air-entry pressure head, Nachabe and Duke equation calculation of water greater than the measured values of the specific yield.These results provided a basis to estimate water table fluctuation under shallow water table.

Keywords:specific yield the drainage experiment the height of the capillary fringe

1． 前言

地下水浅埋深的变化反映着地下水包气带中由于植物根系蒸发蒸腾、潜水面的蒸发,地表和地下径流引起的水分通量的变化.给水度是计算潜水位以上包气带中的水在重力作用 动的重要参数,在蒸发、浅层地下水可开采量、农田灌溉和排水的计算及地下水的相关研究中,都直接影响到计算和结果的稳定性.

给水度是指地下水位下降单位深度时单位面积上的释水量【1】.传统运用中认为给水度是常量.但随着认识的不断加深,发现给水度和包气带的释水性有关.雷志栋【2】指出地下水位下降时,土壤的释水量主要是由土壤非饱和区含水量的分布和运移所决定的,因此,给水度是一个和非饱和流有关的概念.并指出给水度的大小不仅和土壤质地有关,还和水位降深、蒸发、入渗强度有关.Duke[3]提出了给水度随着深度变化而变化的公式.张蔚榛【4】由室内土柱实验得出无论土壤的质地如何,水位下降时给水度的数值都随水位降深的加大而增大.在降深相等的情况下,水位下降速度愈大,给水度的数值愈小.Said【5】通过实验的方法,分别用土壤水分探针和浅层观测井持续监测土壤含水率和浅水面以上的水的存储量变化,分析不同土壤的给水度.Nachabe【6】根据定义结合Brooks-Corey公式、非饱和带的质量守恒方程等土壤水基本方程及土壤含水率数据分析,提出浅埋深情况下,在排水过程中给水度随时间和深度变化的表达式.

地下水论文参考资料：

结论：地下水浅埋深条件下给水度和水位降深关系为适合地下水论文写作的大学硕士及相关本科毕业论文，相关打井怎么知道地下有水开题报告范文和学术职称论文参考文献下载。