NUMERICAL ANALYSIS OF ROCKFALL IMPACT IN LARGE KARST CAVES OF MOUNTAIN TUNNELS
This paper studies the impact of possible rockfall in the karst cave on the structural stress of the moun-tain tunnel.A finite element model of the tunnel structure is established to analyzed the influence of changes in inter-nal forces under different weight of falling rocks,which is based on a mountain tunnel project with a large karst.The results indicate that the internal forces of the lining arch foot and arch crown are relatively large,and the lining struc-ture needs to consider the appropriate expansion of the arch foot.As the weight of falling rocks increases,the in-crease in structural bending moment is smaller than the increase in structural axial force.In addition,when the maxi-mum weight of falling stones at a height of 35 m is 80 tons,the outer arch lining of the tunnel meets the design re-quirements for ultimate bearing capacity.This study may provide the reference for the analysis of rockfall treatment in similar projects.
karst caves in mountain tunnelrockfall impactultimate weight of falling rocks
NETL
NSTL
万方数据
