分层一次爆破成井精确延时爆破参数研究

Precise Time-Delay Blasting Parameters of Stratified Single Blasting Well Completion

为了研究精确延时微差起爆对一次成井分层爆破效果的影响,理论计算了层内孔间微差时间,利用LS-DYNA软件,采用JH-2岩石模型,模拟了大直径深孔一次成井爆破中的精确延时分层起爆,分析了井筒岩石的损伤演化过程,试验验证了延期时间参数。结果表明,层间采用18 ms延期时间时,爆破效果最佳。结合理论分析和数值模拟结果确定了一次成井的延期时间方案。井筒的成形大致相似,其特征截面面积相似度在83.4%~96.6%之间。通过理论分析、数值模拟和现场试验获得了一次爆破成井工程的精确延时微差分层爆破方法,具有实际应用价值。

To investigate effects of precise millisecond time delay detonation on the layered blasting in a single well completion,the millisecond time between holes within the layer was determined by theoretical calculation,and the JH-2 rock model was used in LS-DYNA software to simulate the precise delayed layered detonation in a single well completion blasting of large-diameter deep holes.Blasting effects of two types of delay time were compared,and the process of rock damage evolution in the wellbore was analyzed,finally field tests were conducted to verify the delay time parameters.The numerical calculation results revealed that through considering a comprehensive analysis of the dynamic rock damage process,the characteristic crosssectional area of the blasting chamber,and the extent of rock damage,a delay time of 18 ms between layers of blasting proved to be more effective.The optimal delay time was determined by theoretical analysis and numerical simulations.Both field tests and numerical simulations demonstrated that the wellbore formation closely matched in the selected cross-sectional area characteristics,with a similarity ranging from 83.4% to96.6% and an average similarity of 92.4%.This study highlights that the precise millisecond time delay layered blasting method,obtained through the combination of theoretical analysis,numerical simulation,and field tests(referred to as the “trinity analysis method”),providing reliable and accurate results.It holds practical value and is of significant importance for guiding real-world applications in single blasting well completion projects.