引水隧洞施工爆破对上覆滑坡体的影响研究  

Research on the Influence of Blasting on Overlying Landslide in the Construction of Diversion Tunnel

作　　者：贾澄澄 卓莉[1] 肖明砾[1] 谢红强[1] 何江达[1] 

机构地区：[1]四川大学水力学与山区河流开发保护国家重点实验室,水利水电学院,四川成都610065

出　　处：《中国农村水利水电》2017年第8期180-184,共5页China Rural Water and Hydropower

基　　金：国家重点基础研究发展计划(973)项目(2015CB057903);国家自然科学基金资助项目(51079092)

摘　　要：基于爆破荷载的等效施加方法,采用动力有限元法对水电站引水隧洞施工爆破振动效应进行数值模拟,选择有代表性的特征点,分析爆破作用下振动位移、速度、加速度特性以及不同爆心距部位的振动及衰减规律,利用Geo Studio计算施工爆破前后丹巴滑坡的稳定安全系数,探明爆破振动对丹巴滑坡体的稳定性影响。结果表明:离爆源的距离越近,质点的振动响应越大,且振动衰减也较快,当爆心距足够大时,水平向的振动幅值和铅直向值差不多,此时爆破产生的振动影响很小。振速峰值在爆心距15 m以内衰减速率最快,在爆心距100 m范围外,振速峰值小于0.2 cm/s。刚体极限平衡法和有限元法两种方法计算得到的滑坡稳定安全系数均满足规范要求,即隧洞爆破不会对丹巴滑坡体的稳定和安全造成危害。The blasting vibration effect in the construction of the diversion tunnel of a hydropower station is simulated on the basis of equivalent application method of blasting load and dynamic finite element method. Representative feature points are selected and the characteristics of vibration displacement,velocity and acceleration are analyzed. Moreover,the vibration and attenuation law of different explosion center distance parts are also analyzed.Stability safety factors of Danba landslide before and after construction blasting are calculated by using Geo-studio and the influence of blasting vibration on the stability of Danba landslide is proved. The results show that the closer the distance away from the explosion source,the greater the vibration frequency and amplitude of the particle,and the vibration attenuation is also faster. When the distance is large enough,the horizontal and vertical vibration amplitude value are about the same and vibration effect caused by blasting at this time is very small. The peak velocity of the vibration velocity is the fastest in the explosion center distance of 15 m,and in the range of 100 m,the peak value of vibration velocity is less than 0. 2 cm/s. The stability safety factor calculated by the two methods,the limit equilibrium method and the finite element method,can meet the requirements. Tunnel blasting does no harm to the safety and stability of Danba landslide.

关 键 词：爆破 振动位移 振速 振动效应 衰减规律 稳定 

分 类 号：TV542[水利工程—水利水电工程]