浸没评价中二元阶地水位雍高值的计算方法对比  

Comparation of Calculation Method for the Banked-up Water Level of Double-Layer Structural Terrace in the Immersion Evaluation

作　　者：胡广冲[1] 梁杏[1] 潘欢迎[1] 刘亚磊[1] 

机构地区：[1]中国地质大学环境学院,武汉430074

出　　处：《地质科技情报》2015年第1期191-197,共7页Geological Science and Technology Information

基　　金：国家自然科学基金项目(41272258)

摘　　要：在黏土层饱水带表达式进一步完善的基础上,以长江中下游某研究区线性排列的5个钻孔数据为例,对湖区蓄水后剖面地下水位雍高值分别用卡明斯基法（KM）和结合水动力学法（BDM）进行了计算,结合毛细上升高度和基础埋深圈划出浸没影响范围,对比了2种方法在二元阶地浸没评价中的差异性。研究结果表明：具有二元结构的细粒土层,且上下两岩层渗透系数相差达到104数量级时,二元结构的含水层水动力条件发生变化,地下水流动由潜水二维流转变为承压一维流,此时二元结构的下层更接近承压含水层的性质;渗透系数相差在10^0～10^4数量级以内,随着K_1/K_2不断减小,地下水位雍高值均减小,但是其影响长度却增加;上层含水岩层采用结合水动力学法（BDM）计算出的水位雍高值（平均值0.7m）明显小于卡明斯基法（KM）的计算值（平均值5.5m）,圈划出的浸没面积是卡明斯基法（KM）圈划面积的91%,二元结构阶地浸没评价采用结合水动力学法（BDM）计算的雍高水位值更合理。On the basis of the improved equation of cohesive-soil saturation zone, this paper calculated and compared the phreatie water level before and after the lake impoundment by Kaminski Method （KM） and Bond-water Dynamics Method （BDM）. Data was collected from five boreholes which are linear located in the middle and lower reaches of Yangtze River. This paper also compared the differences in evaluating the double-layer structural terrace submerged between KM and BDM by integrating with immersion scope which was drawn from capillary rise height and embedded depth of foundation. The following conclusions were drawn： the double-layer phreatic hydrodynamic conditions changed when the groundwater was in the nature of the pressure and the upper and lower permeability coefficient reached 104 orders of magnitude in the double-layer structural area. Within the magnitude of 10^0-10^4 , as the falling of K_1/K_2, the high wa- ter level is reducing, but its influence length is increasing. The banked-up water level calculated by BDM （with a mean of 0.7 m） is much smaller than that calculated by KM （with a mean of 5.5 m） ; immersion scope calculated by BDM is 91% of which calculated by KM; the banked-up water level calculated by BDM is more reasonable than which calculated by KM in the double-layer structural area.

关 键 词：黏土层饱水带 卡明斯基法 结合水动力学法 浸没范围 

分 类 号：P641.2[天文地球—地质矿产勘探]