基于Winpest反演分析的降雨入渗补给量分区

Rainfall Infiltration Recharge Partition Based on Winpest Inversion Analysis

在水文地质条件复杂地区进行地下水数值模拟时,需要对降雨入渗补给量进行主观确定,参数识别过程比较复杂。利用Modflow软件,建立了Winpest反演模型对渗透系数进行优化,并通过分析反演过程中观测孔模拟水位和实测水位的拟合情况,进行降雨入渗补给量分区优化。将该模型运用于壁板坡隧道隧址区,结果表明:研究区需先按表层出露的不同层位进行降雨入渗补给量初次分区,再对已有分区按不同高程范围进行二次分区和降雨入渗补给量优化方能实现地下水初始渗流场的高精度拟合。利用Winpest反演分析方法,降低了人为设定降雨入渗补给量的盲目性,为水文地质条件复杂地区的地下水初始渗流场数值模拟提供了一种更加快捷高效的途径。

In the numerical groundwater flow simulation of areas with complex hydrogeologieal conditions, the rainfall infiltra- tion recharge rate is usually assumed, which results in complicated model parameter identification. In this study, Modflow soft- ware was used to develop the Winpest inversion model, which can optimize hydraulic conductivities and rainfall infiltration re- charge partition based on the fitting between the measured and simulated water levels. The model was applied to Bibanpo tunnel zone in XX County of XX Province. The results showed that the rainfall infiltration recharge of the study area can be partitioned initially according to the different layers of surface outcrops, and then the partitions can be divided again based on different ele- vations and optimized to realize the high-precision fitting of initial groundwater seepage field. The Winpest inversion analysis method can reduce the blindness of assumed rainfall infiltration recharge and thus offer a more efficient and faster approach for modeling the initial groundwater seepage field with complicated hydrogeological conditions.