Rockfall is an important, ongoing and challenging socioeconomic issue at many locations worldwide. With the increasing demands for improved rockfall evaluation and mitigation, the Transportation Research Board (TRB), one of the major divisions of the National Academies, therefore has recently developed and published an extensively researched book, Rockfall: Characterization and Control, devoted to all aspects of rockfall characterization, analysis, and mitigation.
Rockfall Analyst: a 3-D rockfall simulation model developed by a research group led by Dr. LAN Hengxing from IGSNRR has been reported in the Chapter 9, Modeling and Prediction of Rockfall. This chapter discusses and compares major approaches and modes for the 3-D quantitative modeling and prediction of rockfall. RockFall Analyst is a recently developed 3-D model which allows a full spatial evaluation of rockfall events. It differs from the other described 3-D rockfall simulation programs in that it is not a stand-alone program but is an extension of ArcGIS. This linkage provides it with powerful analytical capabilities and an attractive user interface.
RockFall Analyst has two major components: 3-D rockfall trajectory simulation (Component 1) and geostatistics-based raster spatial modeling of rockfall hazard (Component 2). Typical sequence of steps has been summarized in assessing rockfall hazards with the two components of RockFall Analyst.
Component 1 of RockFall Analyst performs 3-D rockfall trajectory simulation to evaluate rock block motions. It is concerned with free fall (including airborne rebound trajectories) and combined rolling and sliding motions and with impact dynamics. A detailed description of the computational algorithms used by RockFall Analyst has been illustrated to determine impact responses and to compute rolling and sliding block motion.
Component 2 of Rockfall Analyst performs the raster spatial modeling to implement the spatial distribution modeling on the predicted rockfall trajectories by using raster GIS functions. It undertakes a probabilistic assessment of the spatial distribution of rockfall hazard. The four-step process is developed for converting the Component 1 trajectory information produced in vector form related to each trajectory path to a raster form required by RockFall Analyst Component 2. Geostatistical spatial interpretation procedures and neighborhood filtering and smoothing functions allow for the computation of probabilities for spatial frequency, potential energies and kinetic energies and final hazard.
The book also illustrates case studies for rockfall hazard assessment using Rockfall Analyst. Rockfall analyst has been extensively used in a large number of organizations in over 30 counties worldwide, including universities, academic institutions and the governments. It has been involved in many internationally well-known projects: ground hazard risk assessment for Canadian railways; infrastructure safety assessment in Alps and post-seismic hazard assessment and reconstruction in China, etc..
