1.China Railway th Construction Bureau Fifth Engineering Group Corporation;2.Civil Engineering School,Henan University of Science and Technology
There is high in-situ stress in the rock mass of deep-buried tunnels, and rock bursts are prone to occur in the surrounding rock with high rock strength, which affects the stability of the surrounding rock. The Bijiashan Highway Tunnel is deeply buried. In order to reduce its safety construction risk. In this paper, the properties of surrounding rocks were studied through mechanical experiments of rock samples in the engineering area, and a three-dimensional finite element geological model was established to invert the in-situ stress field in the tunnel site area based on in-situ stress data. Finally, the Gu-Tao rockburst criterion and the R_b/σ_1 criterion were used to predict the rockburst state of the Bijiashan Tunnel. The results show that the rock mass in the tunnel engineering area has a moderate and strong rockburst tendency. The in-situ stress field along the tunnel is dominated by the gravity stress field, and the rock mass in most sections is in an extremely high stress state. The angle between the maximum horizontal principal stress and the tunnel is small, which is beneficial to the surrounding rock stability. After excavation, the peak of the maximum principal stress of the surrounding rock of the tunnel on the whole line is 63.2MPa, which all occur on the sidewall of the section, so there is a greater possibility of rockburst in this part. Rockburst is likely to occur in 24% of the sections along the tunnel, and it is dominated by moderate and high rockburst activities. The results of rockburst prediction can provide references for tunnel excavation and disaster prevention.
孙峰伟,乔栋磊,安艳军,等. 笔架山深埋公路隧道高地应力场特征分析及岩爆预测[J]. 科学技术与工程, , ():复制