基于无人机航拍的景观平衡石模型构建及失稳过程模拟

Numerical model of a landscape balancing rock based on UAV and simulation of rock instability

景观平衡石在长期地自然侵蚀或人为扰动下,自身的稳定性也在持续劣化,一旦超过平衡界限,必将带来灾难性的后果。目前,景观平衡石的数值模型尚不能精确地描述其真实几何形态,同时已有数值分析方法在兼顾复杂接触处理以及真实时间的动态运动过程模拟方面尚有不足。因此,为了能够更为准确地评估景观平衡石在灾变启动后的运动特征,基于三维非连续变形分析方法(3D-DDA)构建了一套能够解决上述难题的完整的景观平衡石失稳全过程模拟体系。首先,基于无人机航拍建模技术生成真实的景观石和边坡的外貌形态;然后,根据所提取的点云信息,发展了一种复杂地质体的三维DDA模型的构建方法;进而,利用自主研发的基于接触势的三维DDA方法(3D-CPDDA)对景观石失稳灾害全过程进行了模拟;最后,得到了景观石的完整失稳运动轨迹和冲击速度等相关信息。

Exposing to long-term natural erosion or human disturbance,the stability of landscape balancing rocks is continuously deteriorating and needs to be adequately evaluated.So far numerical models for the evaluation cannot reasonably describe the geometric shape,consider complex contacts between rocks and its bedrock,and thus cannot simulate the dynamic motion processes in real time.Once the equilibrium of the rock is broken,there will be disastrous consequences.To simulate the motion characteristics of landscape balancing rocks,a numerical method was proposed based on the 3-Dimensional Discontinuous Deformation Analysis(3D-DDA)method.First,the geometric appearance of landscape balancing rocks and slopes was characterized using UAV aerial photography technology.Then,based on the extracted point cloud information,a numerical model based on 3D-DDA was built to describe the geological characteristics.Furthermore,the entire instability process of landscape balancing rocks was simulated using a three-dimensional contact potential-based DDA method(3D-CPDDA)developed by the authors.Finally,the trajectory and impact velocity of the rocks were estimated.