基于扩散波近似方程的降雨边界处理的改进  

Improvement of rainfall boundary treatment based on the diffusion wave approximation equation

作　　者：王旭[1] 董梅[1] 孔梦悦 邓云鹏 徐日庆[1] 龚晓南[1] WANG Xu;DONG Mei;KONG Meng-yue;DENG Yun-peng;XU Ri-qing;GONG Xiao-nan(Research Center of Coastal and Urban Geotechnical Engineering,Zhejiang University,Hangzhou,Zhejiang 310058,China;Hangzhou Archaeological Ruins of Liangzhu City World Heritage Monitoring and Manager Center,Hangzhou,Zhejiang 311113,China)

机构地区：[1]浙江大学滨海和城市岩土工程研究中心,浙江杭州310058 [2]杭州良渚古城遗址世界遗产监测管理中心,浙江杭州311113

出　　处：《岩土力学》2023年第6期1761-1770,共10页Rock and Soil Mechanics

基　　金：浙江省“尖兵”“领雁”研发攻关计划(No.2022C03180);浙江省文物保护科技项目(No.2021021)。

摘　　要：在降雨入渗模拟中,传统的降雨边界不能准确地反映坡面积水深度变化对坡面实际入渗率的影响。基于扩散波近似方程改进了传统的降雨边界,使得在强降雨条件下坡面积水深度动态变化可以和实际入渗率进行耦合计算,并且通过两个经典试验验证了改进边界的准确性。后将该改进边界用于工程实例计算,结果表明:(1)改进的降雨边界可以实现集中型降雨条件下流量边界与压力水头边界的实时动态转换;(2)当降雨边界为压力水头边界时,改进边界计算出的理论上坡面积水深度最深的位置出现在坡趾处;在降雨后期坡面退水阶段,积水深度可忽略不计,理论上积水深度最深的位置出现在平坦坡面与陡峭坡面的交汇处。During the simulation of rainfall infiltration,the conventional rainfall boundary cannot accurately reflect the influence of the variation of ponding water depth on the actual rainfall infiltration calculation.To address this issue,the conventional rainfall boundary is improved by incorporating the diffusion wave approximation equation,which allows for the coupling of ponding water depth variations with actual infiltration during heavy rainfall events.To confirm the precision of the improved boundary,two classical experimental cases are tested.The improved boundary is subsequently applied to the simulation of an actual engineering scenario.It is revealed that:(1)the improved rainfall boundary is capable of achieving real-time dynamic conversion between flow and pressure boundaries;(2)when the rainfall boundary functions as the pressure head boundary,the location with the theoretically deepest ponding water depth on the slope surface,as calculated by the improved boundary,manifests at the slope toe.Conversely,when the rainfall boundary serves as the flow boundary during the later stages of rainfall,the ponding water depth becomes negligible,and the location with the theoretical deepest ponding water depth arises at the intersection of the flat slope surface and the steep surface.

关 键 词：降雨边界 渗流 扩散波近似方程 实时动态转换 

分 类 号：TU42[建筑科学—岩土工程]