Some thoughts on dangerous rock mass for some highway tunnel import slope

China is a mountainous country,and the mountainous area is about two-thirds of the land area.In mountainous areas,constraints and the impact of the various geological disasters growth restrict and affect the local socio-economic development.Especially,collapse,dangerous rock mass disasters have seriously affected the traffic construcion.With the development of China's transportation industry,the long miles of road over the mountains have increasingly complex geological conditions of the tunnel through the mountain.Shanxi Changping Highway is part of the highway connecting Changzhi city and Anyang city.Changping Highway Hongtiguan ultra-long tunnel is on the left bank of the rainbow river canyon.Above the tunnel entrance,there are approximately more than 20,000 m3 of dangerous rock mass,which threatens the Baimutang Bridge safety between the tunnel portal and the tunnel connection.This paper surveys the engineering geological conditions of the tunnel mouth and the dangerous rock mass,analyzes the dangerous rock mass formation mechanism and influencing factors,and by the indoor calculation,researches the dangerous rock stability and strain fields.Finally,this paper discusses the dangerous rock disaster prevention technology.