中文摘要：

通过室内大比例尺相似模拟试验对掌子面锚杆预加固技术进行探讨,并且进行洞周预加固试验辅助对比分析,以明确掌子面锚杆作用特点及机制。通过分析试验位移和应力场特征,得到以下几点认识：（1）掌子面锚杆所引起的纵向压力拱范围小于毛洞及小导管,能有效依靠拱效应来传递分配荷载,维持围岩稳定;（2）掌子面锚杆对隧道掌子面前方垂直及水平方向应力的良好控制是形成有效纵向承载拱的基本前提,使得纵向拱具有较强的承载能力;（3）掌子面锚杆能有效控制掌子面挤出变形。研究成果对软弱围岩隧道修建具有一定指导意义。

英文摘要：

Pre-reinforcement technology of tunnel face bolt is studied through large-scale similarity model test.A series of forepoling pre-reinforcement model tests around the tunnel as auxiliary contrast analysis are conducted to confirm the characteristics and mechanism of tunnel face bolt.By analyzing the model test results and stress field characteristics,the conclusions can be drawn as follows：（1） It is verified that tunnel face bolt improves the stability of the surrounding rock,relying on longitudinal arching effect by means of load transferring and distributing.In addition,the extent of longitudinal pressure arch for the case of face bolt reinforced is less than that of the case of non-reinforced tunnel and small pipe reinforced;（2） The excellent control effects of surrounding rock stress in front of tunnel face in horizontal and vertical directions by tunnel face bolt are the basic premise of forming effective longitudinal bearing arch.So the longitudinal pressure arch possesses great ultimate bearing capacity.（3） The tunnel face bolt can effectively control the extrusion deformation of tunnel face.The study results have important engineering significance for the construction of tunnel with weak surrounding rock.