Geohazards, reflection and challenges in Mountain tunnel construction of China: a data collection from 2002 to 2018

In face of the complicated and changing geological conditions, safety issue is always a primary concern during the construction phase of tunnel in the mountainous regions of China. This Express Letter reports data collection concerning the geo-hazardous events recorded in tunnel system in the period from 2002 to 2018. These accidents include collapse, water inrush, gas explosion, portal landslide, suffocation and avalanche. A total of 97 geohazard events resulted in 393 deaths, 467 injuries and 51 missing. Statistical results indicate that collapse is the primary geohazard in mountain tunnel construction. The data confirmed a high correlation between the number of casualties and geohazard accidents quantity. It is also observed that water inrush is more likely to happen in karst region, while the collapse is mainly recorded in loess and karst areas. During the period under the review, the data illustrates an overall decrease of casualties and geohazard events, but it still faces a grim situation regarding the geohazard prevention in mountain tunnels construction of China. Hence, countermeasures and future research attempts focusing on geohazards prevention and mitigation are recommended.