基于卸荷理论,采用岩土差分软件FLAC分析高埋深作用下不同片理角度岩体对开挖洞室变形的影响。不同片理角度下隧洞模型水平向、竖直向位移以及塑性区对比可以看出,卸荷作用下片理角度对隧洞稳定性影响较大。随着岩石片理角度的增大,隧洞水平方向位移逐渐增大,隧洞周围关键点竖直向位移先增大后减小,当岩石片理角度为40°~60°时,竖直向位移量最小;隧洞周围的岩体塑性区在洞轴两侧大致呈X形分布,塑性区方向、大小及位置与片理角度关系密切;当岩体承受同样的荷载作用时,岩体节理方向与隧洞夹角的变化使得隧洞周围的变形差异较大,在实际工程中应注意岩石片理特性对工程开挖的影响。
Based on unloading theory., it used tile engineering difference software FLAC to simulate tunnel excavation under different schis- tose angles and analyze tile impact of the deformation at high depth. Under different schistose angles, by contrast the x displacement, y dis- placement and plastic zone, the angle have a great influence on the stability of the tunnel under the effect of unloading. With the increase of rock schistositv angle, the x displacement of model increased gradually, the y displacement increased first and then decreased, and the y dis- placement had the minimum displacement of rock tunnel when the rock schistosity angle of 40° to 60°. Plastic zone around the hob' axis tm both sides was roughly X distribution. The plastic zone size and direction had a close relationship to the placement and schistnsity angle. When the rock load at the same direction, the different rock schistosity angles make a big difference to the deformation of the tunnel, so we should pay attention t~/the influence of the characteristics of rock schistosity to the excavation in practical engineering.