Monitoring And Analysis On Stability In Balang Tunnel

Along with the rapid development of the transportation system in China,the status of tunnel engineering is becoming more and more prominent,it reduces construction mileage of the highway,railway,but also improves the alignment.Our country is vast,but the mountains,rivers,lakes are vertical,they seriously affect the construction of transportation network,only to let the tunnel engineering developing so that it can solve the present situation which the transportation is insufficient,therefore the construction of the tunnel shows the trend of increasing year by year.But the tunnel project in China started late,it is still in the developing stage,and the influencing factors for deformation of tunnel surrounding rock are many,after excavation,stability of tunnel surrounding rock is still the focus at this stage.Based on the Lang mountain tunnel,in this paper,research works and achievements included as follows:According to the actual geological conditions where the balang mountain tunnel was in,made a scheme of the monitoring for balang mountain tunnel.The main influencing factors of the stability of surrounding rock and the interaction between these factors at the present stage were discussed,the factors that influence the stability of surrounding rock were analyzed in combination with practical situations and methods of section excavation based on the balang mountain tunnel.Research showed that,the surrounding rock classification and surrounding rock structure had a great influence on stability of surrounding rock.Monitoring data of measuring section was fitted and forecasted by using RBF neural network method,the stability of surrounding rock was judged in combination with the surrounding rock deformation and the deformation trend,and the method of regression analysis was contrasted.The results fingered that the RBF neural network method had higher practical value in monitoring tunnel test,and more accurately reflected the deformation law of surrounding rock with time;the stability of surrounding rock had a closely relationship with rock classification,construction mode,supporting structure,geological conditions and so on.The construction processes of surrounding rock were simulated by using numerical simulation software based on the balang mountain tunnel,and the surrounding rock deformation of various excavation method was contrasted with support and without support conditions,so got the law of stress-strain of different rock classification and different excavation method.The study found that section under various conditions was damaged of different degrees by tension damage and shear failure,tensile failure occurred mainly in the vault and floor,shear failure occurred in the arch waist and foundation,for these parts,timely support measures could improve the surrounding rock stress concentration,and improve the stability of surrounding rock,so that the project was always in good working condition.For the data processing of the tunnel monitoring measurement and construction supportof similar tunnel engineering,the results of this study could provide some application and reference value.