A review and summary of the classification system, triggering factors, and global distribution of high and steep dangerous rocks

High and Steep Dangerous Rocks (HSDRs) are widespread worldwide, and have always been one of the hot research topics in the field of engineering geology. To enable researchers in this field to better clarify the research object, content, and key scientific issues throughout their research process. This paper summarizes from previous studies: the classification system, triggering factors, and global distribution of HSDRs. This paper has garnered the following new insights and findings: (1) A new classification system for HSDRs has been modified and improved, named Shape Features-Stress State (SFSS). SFSS classification system has three basic categories, five general categories and ten subcategories; (2) The main triggering factors for the instability of HSDRs include seismic effect, glacial effect, natural rainfall effect and river effect. The theoretical study of mechanical models under each type of triggering factors has specificity under SFSS classification system; (3) A global distribution map of HSDRs is drawn based on the triggering factors, covering North America, South America, Europe, Asia, Africa, Oceania and Antarctica. Researchers in this field can refer to the classification system, triggering factors, and global distribution of HSDRs presented in this paper to conduct targeted studies, thereby facilitating the efficient advancement of research outcomes related to HSDRs.