考虑植被力学水力作用的洪泽湖堤防加固效果分析

Reinforcement effects of Hongze Lake embankment considering hydro-mechanical effects of vegetation

为研究植被力学水力作用的机理,引入根系吸水分布函数描述不同根系构型的吸水特性,建立了一个用于边坡稳定计算的植被力学水力加固模型,并结合试验结果验证了模型的合理性和有效性。考虑不同根系构型的力学水力作用,对洪泽湖堤防岸坡的典型断面进行加固效果分析,结果表明:根系吸水显著提高了土体基质吸力,其影响范围大约为2.5倍根系深度;在根系吸水的初始阶段,不同根系构型所产生的差异较小,但随着时间逐渐增加,不同根系构型的差异逐渐增大;植被力学水力作用可以显著提高堤防岸坡的稳定性,24 h降雨后,根系加固下的安全系数约为裸土岸坡的1.4倍。

To study the mechanical and hydrological mechanism of vegetation,the water absorption distribution function of plant root was introduced to describe the water uptake characteristics of different root architectures,and the calculation model considering the hydro-mechanical reinforcement of vegetation was established for the slope stability analysis.The rationality and validity of the model were verified by combining the experimental results.Considering the hydro-mechanical effects of different root architectures,the reinforcement effects of typical sections of bank slope in Hongze Lake embankment was carried out.The results showed that the matric suction of soil was significantly improved by the root water uptake,and the influence range was about 2.5 times the root depth;in the initial stage of root water uptake,the difference between different root architectures was small,but with the gradual increase of time,the difference between different root architectures gradually increased;the hydro-mechanical effects of vegetation can significantly improve the stability of embankment slope,and after 24 hours of rainfall,the factor of safety under root reinforcement is about 1.4 times that of bare soil bank slope.