A Stochastic Rockfall Model Related to Random Ground Roughness Based on Three-Dimensional Discontinuous Deformation Analysis
A Stochastic Rockfall Model Related to Random Ground Roughness Based on Three-Dimensional Discontinuous Deformation Analysis
复制标题
基于三维不连续变形分析的随机地表粗糙度随机落石模型
DOI：
10.3389/feart.2021.819751
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发表时间：
2021-12
影响因子：
2.9
通讯作者：
Hong Zhang
中科院分区：
文献类型：
--
作者：
Lu Zheng;Zhiyuan Zhu;Qi Wei;Kaihui Ren;Yanqiang Wu;Wei Wu;Hong Zhang
使用可行的3-D数值方法已成为解决与落石危险有关的问题的关键。虽然有几个复杂程度不同的模型可用，但与某些模型输入有关的某些轨迹和撞击动力学可能落在落石观测区，但很少根据反映其范围的情况进行校准，特别是横向偏差。一个主要的困难在于缺乏对冲击回弹过程中的表观随机性的模拟，从而导致地面粗糙度和块体不规则性。该模型基于三维非连续变形分析(3D DDA)。尽管与以往的三维DDA模拟有相似之处，但本文提出的模型包含了几个新的概念：(1)地面粗糙度被表示为DEM地形网格点上高度摄动引起的坡角的随机变化；(2)块体不规则性直接使用多面体数据来模拟；(3)引入了一种缩放的速度恢复关系来考虑入射速度及其角度。撞击时反弹速度的横向偏差，无论是方向还是数值，都可以通过横向扰动地面方向来解释，从而导致跳动方向的分散。该模型具有较好的随机性，能够较好地描述落石过程。在这项研究中，利用三维动态分析研究了落石的动力学行为，并考察了在不同地表粗糙度水平的台阶边坡上移动的石块的球形性的作用。用累积分布函数(CDF)进行参数分析，研究跳跃的空间分布(跳跃距离和侧向位移)、速度和跳跃高度。讨论了这些因素对块体形状和地面粗糙度的影响。这表明地表粗糙度放大了随机性，并对系统的动力行为起着重要作用；块体球度的不规则性将进一步放大随机性，特别是当岩石尺寸与粗糙度水平相比相对较小时。在模拟落石问题时，应考虑这两种不规则性。根据一系列现场数据集对新模型进行进一步校准是至关重要的。
The use of feasible 3-D numerical methods has become essential for addressing problems related to rockfall hazard. Although several models with various degrees of complexity are available, certain trajectories and impact dynamics related to some model inputs could fall in the rockfall observations area but are rarely calibrated against reflecting its range, especially the lateral deviations. A major difficulty exists in the lack of simulating the apparent randomness during the impact-rebound process leading to both ground roughness and block irregularities. The model presented here is based on three-dimensional discontinuous deformation analysis (3-D DDA). Despite similarities to previous simulations using 3-D DDA, the model presented here incorporates several novel concepts: (1) ground roughness is represented as a random change of slope angle by height perturbation at a grid point in DEM terrain; (2) block irregularities are modelled directly using polyhedron data; (3) a scaled velocity restitution relationship is introduced to consider incident velocity and its angle. Lateral deviations of rebound velocity, both direction and value, at impact are similarly accounted for by perturbing the ground orientation laterally, thus inducing scatter of run-out directions. With these features, the model is capable to describe the stochastic rockfall dynamics. In this study, 3-D DDA was then conducted to investigate the dynamic behavior of the rockfall and examine the role of sphericity of the rock block travelling on bench slopes with different ground roughness levels. Parametric analyses were carried out in terms of cumulative distribution function (CDF) to investigate for spatial distribution (both runout distance and lateral displacement), velocity and jumping height. The effects of block shape and ground roughness revealed by these factors were discussed. It suggests that ground roughness amplifies the randomness and plays important roles on the dynamic behavior of the system; irregularity from block sphericity will further amplify the randomness especially when the size of the rock is relatively small compared to the roughness level. Both irregularities should be taken into consideration in simulating rockfall problems. Further calibration of the new model against a range of field datasets is essential.
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影响因子：
4.6
作者：
A. Volkwein;K. Schellenberg;V. Labiouse;F. Agliardi;F. Berger;F. Bourrier;L. Dorren;W. Gerber
通讯作者：
A. Volkwein;K. Schellenberg;V. Labiouse;F. Agliardi;F. Berger;F. Bourrier;L. Dorren;W. Gerber
DOI：
--
发表时间：
2003
期刊：
--
影响因子：
--
作者：
ChenGuangqi
通讯作者：
ChenGuangqi
影响因子：
6.7
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Z. Ji;Zhi-Jian Chen;Q. Niu;Tianxiao Wang;Hao Song;Tingjian Wang
通讯作者：
Z. Ji;Zhi-Jian Chen;Q. Niu;Tianxiao Wang;Hao Song;Tingjian Wang
DOI：
10.1016/j.ijrmms.2015.05.008
发表时间：
2015-09
影响因子：
7.2
作者：
Hong Zhang;Guang-qi Chen;Lu Zheng;Zheng Han;Ying-bin Zhang;Y. Wu;Shuguang Liu
通讯作者：
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影响因子：
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作者：
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