爆破扰动下既有隧道围岩稳定与安全振速研究工程力学专业论文.docxVIP

AbstractIn Abstract In order to alleviate traffic pressure，A large number of single tunnel needs rebuild to double tunnel or build a new tunnel beside the existing tunnel．At this time， The surrounding rock and the structure of the existing tunnel will be inevitably damaged the disturbance of blasting．How to ensure the surrounding rock of existing tunnel during the process of blasting has become an important project for successful construction．The study of stability and safety vibration velocity of surrounding rock of existing tunnel on the disturbance of blasting is still in the stage of development，mostly through the empirical formula and field test to guide engineering practice，and for the theoretical research of blasting vibration is still very inadequate．In order to explore the rules of dynamic response and safety vibration velocity of surrounding rock of existing tunnel on the disturbance of blasting，the paper use theoretical calculation and numerical simulation methods，and verified by field measurement and model test．The results obtained follows： (1)In this paper，formula of safety vibration velocity of surrounding rock of existing schist tunnel are established based on elastic mechanics and structural mechanics．It is concluded that the tensile stress of surrounding rock at the most dangerous point gradually increases、Ⅳitll the increase of the angle of rock stratum， the tunnel radius，the thickness of the over burden layer and the included angle of stratified rock mass at different rates，attenuation with the increase of the thickness of rock stratum，the power increases with the increase of the ratio of the tunnel radius to the thickness of rock statum，but when the product of included angle of stratified rock mass and the ratio of radius to thickness is fixed，the tensile stress is constant．At the same time，according to the theory criterion of maximum principal tensile stress，the calculation formula of the maximum vibration velocity of the most dangerous point