邻近既有铁路山体大规模爆破开挖安全控制技术研究

Safety Control Technology of Large-Scale Basting Excavation in the Mountain Near the Railway

紧邻既有铁路进行大规模山体爆破开挖,施工环境复杂,既有结构安全标准要求高。通过控制爆破总规模、单孔用药量、单次起爆药量以及增加飞石防护措施,可将爆破振动速度控制在临界值3 cm/s以下,将飞石最大飞散距离控制在临界值200 m以内。进一步优化施工方案后,设定既有线爆破振动安全值为2 cm/s,设定飞石最大飞散距离安全值为20 m。工程案例实施结果表明,各检测点爆破振动速度均小于2 cm/s,飞石最大飞散距离均小于20 m,爆破产生的振动及飞石不会对既有铁路安全产生影响。采取本文所述爆破控制方案能有效控制爆破有害效应,能确保邻近既有铁路爆破开挖施工安全。

The construction environment for carrying out large-scale mountain blasting excavation near the existing Railway is complex,and the safety standards of the existing structures are high.By controlling the total scale of blasting,the dosage of a single hole,the amount of a single initiating charge and increasing the protective measures of flying rocks,the blasting vibration speed is controlled below the critical value of 3 cm/s,the maximum flying distance of flying stones is controlled within the critical value of 200 m.After further optimizing the construction plan,the safety value of the existing line blastingvi bration is set to 2 cm/s,the safety value of the meximun flying distance of flying stones is set to be 20 m.The results of the project indicate that the blasting vibration velocity of each detection point is less than 2 cm/s,the maximum flying distance of flying rocks is less than 20 m,and the vibration generated by blasting and flying stones will not affect the safety of the existing railway.The blasting control scheme demonstrated in this paper can effectively control the harmful effects of blasting and ensure the safety of blasting excavation construction near the existing railway.