Analysis of Rock Burst Characteristics in High Stress Zone of Xianshui River Structural Belt Tunnel
Research purposes:The continuous uplift of the Qinghai-Tibet Plateau has led to prominent high ground stress characteristics in the Xianshuihe structural belt and adjacent areas,with extremely complex ground stress fields.Studying the disaster prone characteristics of high ground stress is helpful for the risk prevention and control of tunnel rockburst,especially in the study of the disaster prone and causative mechanisms of time-delay rockburst.This paper elaborated on the overall understanding of disaster prevention in the Xianshuihe tectonic zone,including its landforms,stratigraphic lithology,structure,and stress field characteristics.Through statistical analysis of approximately 1 300 times rock bursts in tunnels within a distance of nearly 10 km in the region,the characteristics of rock bursts were studied from multiple perspectives such as probability,level,burial depth,location,time,and distance.The five time delayed rock bursts and the characteristics of tunnel time-dependent changes were analyzed,and the future focus of rock burst research was discussed.Research conclusions:(1)The Xianshui River structural belt and its adjacent areas are affected by high ground stress,with hidden and irregular small and micro structures,creating a special disaster prone environment for rock bursts.The randomness of rock bursts is high.(2)The rock burst level of the tunnel in this area is mainly mild,with characteristics of"zone rupture"and brittle deformation.Time delayed rock bursts have a certain degree of"inheritance".(3)It is recommended to strengthen the monitoring and research of low burial type rock bursts,lagging type rock bursts,or potential time-dependent failure of hard rocks in valley stress fields.(4)The research results of this paper can provide reference for rock burst prediction and prevention in similar high stress environments.
Xianshuihe fracture zonedeep buried tunnelshigh ground stress characteristicstime delayed rock burstconstruction rock burst characteristicsrisk prevention and control
万方数据
维普
