# Model Test of Dynamic Response of Living Poles Slope Under Train Loads
## 1 Introduction  
Plant roots have been widely used for the ecological protection of slopes because of their role in reinforcing shallow soils, alleviating topsoil erosion, preventing soil erosion, and being friendly to the environment [1; 2; 3]. The effectiveness of existing plant slopes to control deep landslides (>2 m) is limited by the fact that the root system of most plants is distributed in the shallow layer (1-2 m) of the ground surface [4]. Using living poles is a new form of plant slope support, which comprises living tree poles (willow or elm, etc.) with high vitality implanted into the deep soil layer or its branch cutting inserted into the deep soil layer. After a period of time, the poles will grow roots and branches, thus playing the role of reinforcement and protection for the slope [5], aiming to enhance the stability of the slope through the reinforcement and anti-slip effect of its deep root system.  
To date, it has been proven that living poles implanted in deep layers can achieve reinforcement of deep landslides, and their slope stability under static conditions is significantly improved compared with slopes without living poles [6; 7; 8]. Most of the model tests or numerical analyses for living pole support were studied under static conditions. Different types of living poles were planted on the slopes and the slopes were analyzedusing the finite element software PLAXIS [9]. They demonstrated that the safety factor of the slope increased significantly due to the reinforcement effect of the living poles. The stability of the slope increased with the depth and the number of living poles set. In the medium and long term of the implanted living poles, the root system grew outward along the woody stem and formed a complex with the soil, which not only provided mechanical reinforcement, but also reduced the hydraulic conductivity of the soil to reduce the rainfall infiltration [10]. Living pole support has been applied as an engineering method for slope stabilization in high seasonal rainfall areas of natural forests in New Zealand to combat slope creep and more rapid slope movement [11; 12]. Support slopes with willows, shrubs, and small tree species have proven effective in temperate regions such as Central Europe (Switzerland and Austria), the United Kingdom, and the United States [13; 14].  
The application of live stumps to embankment slopes of small height and gentle slope is a useful attempt, but the construction of a large number of railroads puts the embankment slopes in the high-intensity vibration environment of trains, which are inevitably subjected to periodic or non-periodic vibration loads in frequency and amplitude at any time, and the vibration load of the trains is the most direct causative factor of the dynamic response of the embankment slopes [15; 16; 17]. The literature contains very few studies that examine the dynamic response of the slopes supported by living poles under the action of dynamic train loads. It is important and urgent to investigate the dynamic response characteristics of the slopes supported by living poles.  
Therefore, we designed and produced an indoor model of a soil embankment slope supported by living poles according to similar principles. We simulated the train vibration load on the slope by using a hydraulic pulsation testing machine, and studied the mechanical behavior and deformation of the living poles slope model under the action of train vibration, to provide a reference basis for the prevention and control of the road and railroad slope disasters.