ANALYSIS OF SURROUNDING ROCK STABILITY IN HIGHWAY TUNNELS CROSSING FAULT FRACTURE ZONES
To study the stability of tunnel surrounding rock during excavation through a fault fracture zone,this pa-per focuses on the Wulingtou Tunnel crossing the Zhouwang Fault zone on the Wuhuang Expressway.Using Midas GTS software,the analysis examines the mechanical state of surrounding rock under various conditions,including different step lengths,excavation lengths,fault dip angles,and fault widths.The results indicate that the best stabili-ty occurs with an excavation cycle length of 1.5m and a step length of 10m;both excessively large or small parame-ters negatively affect stability.Additionally,when the fault dip angle is less than 90°,the surrounding rock exhibits smaller displacement and plastic zone area compared to angles greater than 90°,resulting in better stability.As fault width increases,both displacement and plastic zone area enlarge,leading to decreased stability.Therefore,selecting appropriate construction parameters and excavation directions is crucial to minimize disturbance to the tunnel sur-rounding rock.
highway tunnelfault fracture sectionnumerical simulationsurrounding rock stability
万方数据
维普
