爆破动载荷作用下支护结构的动态安全距离研究

地下洞库在开挖过程中,掘进爆破振动对围岩及支护工程的影响不容忽略。锦州地下洞库3北洞罐长934 m,基于地震波传播的空间效应,把3北洞罐分成3段,得出了各段的速度衰减规律。结果表明:洞罐前段衰减速率最快,中段次之,末端衰减最慢。按照新浇筑混凝土的爆破振动安全振速,确定了洞罐掘进在前段、中段和末端的安全距离,研究结果对其他洞罐支护安全距离的选择提供了理论依据。

Study on Dynamic Safety Distance of Supporting Structure Under Dynamic Blasting Load

During the excavation process of underground cavern,the effect of the excavation blasting vibration on the surrounding rock and the supporting project can not be neglected.The 3N cavern in the Jinzhou underground cavern is 934 m long.Based on the spatial effect of seismic wave propagation,the 3N cavern is divided into three sections,obtaining the speed attenuation law of each section.The results showed that the decay rate of the front section is the fastest,followed by the middle,and the final section is the slowest.According to the safe vibration velocity of the blasting vibration of the new pouring concrete,the safety distance in the front,middle and the final section of the cavern were determined.The results provide a theoretical basis for selecting the safety distance of other cavern support.