Accuracy and reliability evaluation of 3D-LS for the discontinuity orientation identification with different registration/georeferencing modes     

Shengming Hu  Zhijian Chen  Chenghui Wan  Lei Huang 《Marine Georesources & Geotechnology》2013,31(10):1196-1204

Abstract

With the aid of three-dimensional laser scanning (3D-LS), a lot of geometric properties of rock discontinuities can be derived from the point cloud data. Due to the complexity of registration and georeferencing of multi-station point data, geological engineers tend to simplify processing by using single-station point data and orienting coarsely. However, there is a lack of accuracy and reliability study in the identification of discontinuity orientations with 3D-LS using different registration/georeferencing modes. In this study, the single-station scanning without registration/georeferencing was applied first to examine the accuracy and reliability of the scanner’s built-in direction system. After that, two types of automated registration/georeferencing modes were examined for the accuracy in rock mass discontinuity analysis. The results show that the dip angle measured by the scanner’s built-in directional system is reliable, accurate and can meet engineering requirements, while the dip direction measured by the scanner’s built-in directional system is unreliable and inaccurate. The dip direction is consistent but inaccurate through the semi-automated registration using natural point features and georeferencing by the scanner’s built-in directional system. Only through real-time kinematic (RTK) registration/georeferencing can the dip direction be reliable and accurate. It is observed that orientations captured by 3D-LS can be more accurate with RTK registration/georeferencing than manual survey.  相似文献   

Dynamic stability analysis of rock slope considering the strength vibration degradation of through-type rock discontinuitiesEI北大核心     

许彬  刘新荣  周小涵  梁越  钟祖良  刘俊  邓志云 《岩土力学》2023,(8):2419-2431

考虑结构面抗剪强度震动退化效应对分析与评价岩质边坡动力稳定性具有重要意义。基于岩石动力试验获取了多因素影响的结构面强度震动退化系数方程,结合极限平衡理论和动态矢量法原理,以UDEC程序作为计算引擎,采用其内置Fish语言编程实时刷新结构面强度特性参数和捕获任意地震历时时刻边坡地震惯性力,并以最小平均安全系数法求解边坡最终动力稳定性评价指标值,从而提出了一种考虑结构面强度震动退化的边坡动力稳定性系数动态算法。研究表明:结构面强度震动退化系数是取决于岩块间循环剪切次数、循环剪切幅度及相对运动速度响应值的动态变量;将该算法应用于含贯通型平直状结构面边坡动力稳定性算例中,其分析结果表明,动力作用时程内考虑结构面强度震动退化的边坡动力稳定性系数较未考虑该效应时的系数衰减更为明显,即前者计算结果更符合一般性自然规律,亦即验证了该算法的可行性;结构面最小强度震动退化系数随动力激励时程变化近似呈负指数函数形式逐渐衰减,且当结构面初始黏聚力(内摩擦角)越大、而坡角(层面倾角)或动荷载幅值(频率)越小时,地震历时过程中边坡最小动力稳定性系数越大,此时边坡最终动力稳定性相对越强。  相似文献