泥石流沟道汇流对堆积危险范围影响的数值模拟研究

Numerical Simulation Study on Hazardous Area for the Confluence Deposit of Gully Debris Flow

利用离散元法和图形处理器(GPU)并行计算手段建立泥石流运动堆积模型,以自然界沟道泥石流汇流后运动堆积特征及危险范围作为模拟参照,利用所构建的泥石流流通槽完成沟道泥石流不同交汇角汇流模拟试验和堆积危险范围预测,实现了泥石流沟道汇流的可视化模拟和数值模拟。试验结果表明,可视化模拟能够模拟出自然界中泥石流自流通区运动汇流后产生堆积的运动特征;数值模拟实现了锐角条件下仅考虑单因素即沟道交汇角对泥石流堆积危险范围影响的模拟试验。此外,利用GPU并行计算的优势可用于模拟大规模泥石流汇流现象,模型的可扩展性为泥石流汇流堆积危险范围分析向更为复杂的地理环境模拟奠定基础。

Featured with suddenness and rapid expansion, the confluence of gully debris flow in the nature can cause huge economic loss to the residents along the accumulation areas. Therefore, it is necessary and urgent to predict the hazardous range for the confluence of gully debris flow. Through utilizing discrete element method and GPU parallel computing approaches, this paper establishes debris-flow deposit model. By taking the debris-flow deposit characteristics after the confluence of gully debris flow in the nature and simplifying the interaction between debris-flow gully, this article completes numerical simulation of debris-flow confluence with different confluent angles and the prediction of deposit hazardous areas. The experiment results indicate that numerical simulation of debris-flow confluence can not only simulate the characteristics of deposit produced by the confluence from circulation areas of debris flow in the nature, but also simulate the reasonable hazardous range for the debris-flow deposit under the action of pressure component and shear force component of different gully confluence angles. In addition, the advantages of GPU parallel computing can be used to simulate the large-scale debris flow confluence phenomena, and the expandability of this model lays simulation basis for analyzing the hazardous range for the confluence accumulation of debris flow in a more complicated geographical environment.