波动水位下河道堤防壤土斜墙截渗分析
Seepage Interception Analysis of Loam Slope Walls in Riverbank Levees Under Fluctuating Water Levels
赵薇 1单建军 2杨正玉 3杨斌 2李思远 1孙树林1
作者信息
- 1. 河海大学 地球科学与工程学院,江苏 南京 211100
- 2. 淮河工程集团有限公司,江苏 徐州 221400
- 3. 江苏省地质矿产局第三地质大队,江苏 南京 212000
- 折叠
摘要
考虑水位波动和防渗墙的尺寸结构对堤防渗流特性的影响,共设计了28 种工况,对比分析波动水位下防渗墙的厚度、防渗墙的嵌入深度和堤基的渗透性对堤防的渗流量、膜后浸润线高度、防渗墙底部及溢出点水力坡降的影响.结果表明,相比防渗墙的厚度变化,增加防渗墙的嵌入深度更能有效控制堤防渗流量、降低膜后浸润线高度和溢出点水力坡降;当嵌入深度为 0～2 m时,水力坡降随嵌入深度的增加而减少,且呈现先快后慢的变化趋势,当嵌入深度超过 2 m以后,水力坡降随嵌入深度的增加而增加,且在5 m时达到峰值,超过 5 m时水力坡降骤降;此外,对于悬挂式防渗墙设计,当坝基渗流量控制在 75%时,溢出点水力坡降均小于 0.25,防渗墙嵌入深度与坝基渗透系数之间存在强对数线性关系,所建拟合公式可用于类似代建工程防渗墙嵌入深度的初步设计或已建工程的渗流控制评估.
Abstract
Considering the influence of water level fluctuations and the dimensional structure of imper-meable walls on the seepage characteristics of embankments,28 scenarios were designed to compare and analyze the effects of the thickness of impermeable walls,the embedding depth of impermeable walls,and the permeability of the embankment based on the seepage flow,the height of the seepage line be-hind the membrane,and the hydraulic slope at the bottom and overflow point of impermeable walls un-der fluctuating water levels.The results indicate that,compared to changes in the thickness of impermea-ble walls,increasing the embedding depth of impermeable walls can more effectively control seepage flow of embankments,reduce the height of the seepage line behind the membrane,and decrease the hy-draulic slope at overflow points.For embedding depths ranging from 0 m to 2 m,the hydraulic slope de-creases initially with increasing depth,showing a trend of rapid decline followed by a slower decrease.Beyond 2 m,the hydraulic slope increases with depth,reaching its peak at 5 m before sharply declining when exceeding 5 m.Additionally,in suspended-type impermeable wall designs,when controlling the dam base seepage at 75%,the hydraulic slope at the overflow point remains below 0.25.A robust loga-rithmic-linear relationship exists between the embedding depth of the impermeable wall and the dam base permeability coefficient.The derived fitting equation can be applied for the preliminary design of impermeable wall embedding depth in similar construction projects or for evaluating seepage control in existing projects.
关键词
波动水位/无粘性砂土/河道堤防/壤土斜墙/渗流分析Key words
wave action/cohesionless sandy soil/river embankment/loam sloping wall/seepage a-nalysis引用本文复制引用
基金项目
中央高校科研业务费专项资金资助项目(2109B42214)
江苏省研究生科研与实践创新及项目(SJCX23_0181)
国家自然科学基金资助项目(41674113)
出版年
2024
NETL
NSTL
万方数据